Technalogix TXV1000 TXV-1000 VHF Transmitter User Manual ContentsTAV1000
Technalogix, Ltd. TXV-1000 VHF Transmitter ContentsTAV1000
Manual-TAV1000
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TAV-1000
POWER AMPLIFIER
NEW
ADVENTURES
IN
BROADCASTING
Technalogix
You’ve already unpacked it, haven’t you? You’ve unpacked it and plugged
it in and turned it on and fiddled with the knobs. No? Okay, good. Please
take a few minutes to read the manual and familiarize yourself with your
new Technalogix power amplifier.
We believe that this manual, and of course our equipment, should be
everything you need to get on the air with superb broadcast quality video.
We understand that a capable and confident user will get the most out of
our product and we have made every attempt to educate readers of all
technical levels. If there is something that is not clear, or you require
further information, please do not hesitate to contact us and we’ll be glad
to help out.
Technalogix Ltd.
#4, 8021 Edgar Industrial Place
Red Deer, Alberta, Canada
T4P 3R3
Phone: 403.347.5400
Fax: 403.347.7444
URL: www.technalogix.ca
Email: technical@technalogix.ca
sales@technalogix.ca
We truly appreciate that you have chosen us as your television broadcast
system supplier. Happy viewing.
Table of Contents
SECTION I- SAFEGUARDS ..............................................................................................I-1
SAFETY AND FIRST AID.....................................................................................................I-2
OPERATING SAFEGUARDS ................................................................................................I-3
SECTION II - WARRANTY............................................................................................. II-1
SECTION III - OVERVIEW...............................................................................................III-1
STANDARD FEATURES.....................................................................................................III-1
PRINCIPLE OF OPERATION...............................................................................................III-2
BLOCK DIAGRAM (TAV-1000) ........................................................................................III-3
BLOCK DIAGRAM (TAV-500)...........................................................................................III-6
BLOCK DIAGRAM (COMBINER/FILTER ENCLOSURE).......................................................III-8
SPECIFICATIONS...............................................................................................................III-9
SECTION IV - RF COMPONENTS................................................................................ IV-1
AMPLIFIER PALLETS....................................................................................................... IV-1
SPLITTER/COMBINER..................................................................................................... IV-4
CIRCULATOR/ISOLATOR ................................................................................................. IV-4
FINAL COMBINER............................................................................................................ IV-5
DIRECTIONAL COUPLER................................................................................................. IV-5
FILTER............................................................................................................................ IV-5
SECTION V - POWER SUPPLY SECTION......................................................................V-1
SECTION VI - MONITOR AND CONTROL SYSTEM....................................................... VI-1
CONTROL BOARD OVERVIEW (SERIES IIH)................................................................... VI-1
POWER SUPPLY COMPONENTS..................................................................................... VI-1
INTERFACE COMPONENTS ............................................................................................. VI-2
SIGNAL CONDITIONING COMPONENTS .......................................................................... VI-3
DISPLAY COMPONENTS ................................................................................................. VI-4
MICROCONTROLLER COMPONENTS............................................................................... VI-5
FAULT SHUTDOWN......................................................................................................... VI-6
ENCLOSURE INTERFACING............................................................................................. VI-7
REMOTE PORT............................................................................................................... VI-7
BILL OF MATERIALS....................................................................................................... VI-7
SCHEMATICS .................................................................................................................. VI-7
SECTION VII - MECHANICAL SECTION.......................................................................VII-1
SECTION VIII - INSTALLATION...................................................................................VIII-1
BUILDING RECOMMENDATIONS.....................................................................................VIII-1
HEATING AND COOLING REQUIREMENTS .....................................................................VIII-2
ELECTRICAL SERVICE RECOMMENDATIONS.................................................................VIII-3
ANTENNA AND TOWER RECOMMENDATIONS................................................................VIII-4
SHELTER SECURITY ......................................................................................................VIII-5
UNPACKING AND INSPECTION.......................................................................................VIII-6
LOCATION AND FUNCTION OF CONTROLS AND CONNECTORS (TAV-500 POWER
AMPLIFIERS)..................................................................................................................VIII-7
LOCATION AND FUNCTION OF CONTROLS AND CONNECTORS (COMBINER/FILTER
ENCLOSURE).................................................................................................................VIII-9
INITIAL HOOK UP.........................................................................................................VIII-11
SECTION IX - OPERATING PROCEDURES................................................................... IX-1
SECTION X - MAINTENANCE AND TROUBLESHOOTING...............................................X-1
TROUBLESHOOTING ........................................................................................................X-2
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I-1
Section I - Safeguards
General Safeguards
This section is written as a general guide to keep all 5 fingers on your hand and is intended for those having
previous knowledge and experience with these kinds of equipment. It is not intended to contain a complete
statement of all safety precautions, which should be observed by personnel using this or other electronic
equipment.
DOCUMENTATION - Read, retain and follow instructions before operating the equipment. There is a
lot of useful information in the manual, and besides, we spent a lot of time writing it!
ENVIRONMENT - To reduce the risk of fire or electric shock, do not expose this equipment to rain,
moisture, or rye and sodas at the company Christmas party. Refer all servicing to qualified service
personnel.
SERVICING - Do not attempt to service this equipment yourself as opening or removing covers can
result in a warm tingly feeling and will void the warranty. Refer all servicing to qualified service
personnel.
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I-2
Safety and First Aid
Personnel engaged in the installation, operation, maintenance, or servicing of electronic equipment are exposed
to the hazard of high voltage. It is imperative that all safety regulations and precautions are consistently
observed. Knowledge of first aid procedures is recommended. The following information is presented as a
reference only.
• At all times, avoid placing any part of the body in series between ground and circuit points, whether power is
on or off.
• Dangerous voltage may be present in equipment even though power is off. Do not open the cabinet. Refer
servicing to qualified service personnel.
• It is the duty of all personnel to be prepared to give adequate emergency first aid treatment and thereby
prevent avoidable loss of life.
• There are three principle degrees of burns, recognizable as follows:
• a first-degree burn reddens the skin.
• a second-degree burn blisters the skin.
• a third degree burn chars the flesh and frequently places the victim in a state of shock accompanied
by respiratory paralysis.
• Respiratory paralysis can cause death by suffocation within seconds. It is imperative that the approved
methods of artificial respiration are initiated immediately and continue until the victim’s breathing is normal.
• A muscular spasm of unconsciousness may render the victim unable to break free of the electric power. If
this is the case, turn the power off immediately.
DO NOT TOUCH THE VICTIM OR YOU MAY SHARE THE SAME PREDICAMENT.
• If the power cannot be turned off immediately, very carefully loop a dry rope, article of clothing, length of
strong cloth or a rolled-up newspaper around the victim and pull the victim free of the power source.
Carefully avoid touching the victim or clothing.
• Once free of the power source, the victim must be placed in a reclining position and covered with a
blanket or newspapers to keep warm. At the first opportunity, enlist help in summoning a doctor. If a
doctor cannot be summoned, transport the victim to the doctor or a hospital. Be sure the victim is kept
well covered and warm while awaiting professional treatment.
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I-3
Operating Safeguards
It is a known fact that our broadcast transmitters and translators enjoy 50-ohm load impedances. So much
so, that it is imperative you maintain 50-ohm impedances throughout your system. In return, your equipment
will provide you with maximum power transfer to the antenna and decreased reflected power heading back
towards the amplifier pallets, reducing the amount of magic smoke that gets let out of the power amplifier.
Before anything is turned on, ensure that there is a 50-ohm path from the output of each stage to the input
of the next, all the way to the antenna.
In addition to maintaining proper 50-ohm impedances throughout the signal chain, it is also important,
whenever possible, to make sure the RF drive going to the input of the power amplifier is removed before
turning on or turning off the DC power supply. This is because all of the RF transistors used in the individual
amplifier pallets are fabricated with LDMOS (Laterally Diffused Metal Oxide Semiconductor) technology.
Nice and linear yes, but they do not like to make any RF power when their supply voltages are not within a
specific range. When you first turn your power amplifier on or off, the DC power supply’s output voltage may
take a while to stable out to a safe operating voltage. Ten seconds wait before applying the RF drive will
ensure no issues arise.
Our power amplifiers are designed to reliably generate a specific RF output power. Failing to adhere to
overdriven amplifier warnings can decrease the reliability of your system, and frankly, makes our repair
department busy and grumpy. If you need to transmit to a little larger coverage, you are better off increasing
antenna gain, and more importantly, antenna height above average terrain. On TV and FM broadcast
frequencies, insufficient antenna height puts an upper limit on your range, regardless of power levels, as the
distance from your antenna to the radio horizon is limited.
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II-
1
Section II - Warranty
Our legalese is straightforward. It is simply designed to give you peace of mind and helps you resist the
temptation to have your electronics friend try to repair your Technalogix product.
Technalogix Ltd. products have been completely tested and found to meet specifications and be in proper
operating condition. They are warranted to be free from defects in materials and workmanship for a period of one
year from the date of shipment. If the system becomes damaged in shipment and there are obvious signs of
damage to the outside of the packaging, notify your courier immediately before that courier walks out the door.
Technalogix Ltd. will not be liable for damages of whatever nature arising out of or in connection with the
equipment or its use thereof. Technalogix does not assume responsibility for injury or damage resulting from the
practices of untrained or unqualified personnel in the handling of this equipment.
Technalogix Ltd. warranty does not include:
• misuse, neglect or accident.
• incorrect wiring and /or improper installation.
• unauthorized repairs, modifications or use in violation of instructions issued by Technalogix.
• incidental or consequential damages as a result of any defect.
• reshipment cost or insurance of the unit or replacement units or parts.
• acts of nature or terrorism.
Technalogix agrees, at our option, to remedy warranted defects or furnish a new part in exchange for any part of
a unit which, under normal installation, use and service, becomes defective. The user will pay for transportation
costs to and from the repair center.
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II-
2
To claim your rights under this warranty:
• Contact Technalogix and describe the problem in as much detail as possible. See troubleshooting section
in this manual. If a solution cannot be found at this time, it may be determined that the unit will have to be
returned to Technalogix for repair, once a Return Materials Authorization (RMA) number is provided.
• Package equipment carefully for prepaid shipment to Technalogix. Include a written description of the
problem experienced, a copy of the original invoice establishing warranty status, and the RMA.
Technalogix reserves the right to make revisions in current production of the equipment and assumes no
obligation to incorporate these changes in earlier models.
Shipping Address:
Technalogix Ltd.
ATTN: RMA#
#4, 8021 Edgar Industrial Place
Red Deer, Alberta, Canada
T4P 3R3
Ph: 403.347.5400
Made in Canada, returned for repairs
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III-
1
Section III - Overview
Standard Features
• Narrow output bandpass filter allows adjacent channel operation
• Front panel Liquid Crystal Display (LCD) to monitor forward and reflected RF power, and DC voltage
• Microcontroller-based monitoring and control ensures amplifier will never be overdriven and high VSWR will
not damage amplifier
• AC circuit breaker on back panel to eliminate replacement of fuses
• All aluminium enclosure maintains power amplifier’s light weight
• Simple design using commonly available parts ensures reliable operation
• Predominate and third-order intermodulation distortion exceeds Industry Canada and FCC specification.
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III-
2
Principle of Operation
The TAV-1000 power amplifier supplies a 1000-watt peak video signal with 10% aural power on any of the VHF
television channels 2 through 13. Please note that channel selection must be made at time of order, as the
transmitter or translator is calibrated and tested to the channel requested and is not field tuneable. The TAV-
1000 power amplifier is a modular solid-state 1000-watt broadcast amplifier utilizing readily available RF
components wherever possible, thus enhancing the serviceability of the equipment. The TAV-1000 features ultra
linear amplification and individual channel RF output bandpass filtering. The amplifier modules are stable for high
reliability and long service life.
The amplification of the TAV-1000 is comprised of (2) TAV-500 500-watt power amplifiers. Firstly, the output of
the modulator or processor gets split into (2) RF signals of equal amplitude. Each output of the 2-way power
divider is then fed into a TAV-500 Power Amplifier. Finally, the outputs of each TAV-500 are combined to
generate 1000-watts of peak visual power in addition to an aural carrier, as seen in the TAV-1000 block diagram.
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TO WATTMETER
AND ANTENNA
1U ENCLOSURE
5U ENCLOSURE
5U ENCLOSURE
5U ENCLOSURE
RF OUT
TAV-500
COMBINER
FILTER
TAV-500
SPLITTER
2-WAY
MODULATOR/PROCESSOR
TAV-1000 Overall Block Diagram
Date: December 17, 2003 Page: 1 of 1
Rev ID
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III-
4
Inside each 500-watt power amplifier, the signal gets split into (2) signals for final amplification using a 2-way
Wilkinson power divider. The final amplification stage is comprised of (2) P400-VHF-L or (2) P400-VHF-H
final amplifiers, for low or high band VHF, respectively. The outputs of the (2) final amplifier pallets are
combined with a 2-way Wilkinson combiner and pass through a dual directional coupler for protection and
monitoring purposes, as illustrated in the following TAV-500 block diagram.
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A=-0.05dB typ.
A=-0.5dB typ.
A=-0.08dB typ.A=-0.08dB typ.
GAIN
COMPENSATION ι
PA1 OUT
PA2 OUT
A=40dB typ. low band VHF
A=34dB typ. high band VHF
A=18dB typ. low band VHF
A=15dB typ. high band VHF
A=18dB typ. low band VHF
A=15dB typ. high band VHF
RF INPUT
RF OUT
PA25-VHF DRIVER
SPLITTER
2-WAY P400-VHF FINAL
P400-VHF FINAL
2-WAY
COMBINER
VV
DIRECTIONAL COUPLER
V
CIRCULATOR
TERMINATION
50 OHM
TAV-500 Block Diagram for use with TAV-1000 Power Amplifiers
Date: December 17, 2003 Page: 1 of 2
Rev ID
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III-
6
After amplification, the signal exits the power amplifier enclosure and goes into the combiner/filter enclosure,
where the signals from each 500-watt amplifier are combined. After combining, the amplified signals are
filtered with a bandpass filter and monitored again with another directional coupler before heading out to an
antenna for broadcast, as depicted in the following combiner block diagram.
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A=-0.6dB to -1.0dB A=-0.05dB
A=-0.45dB
TO WATTMETER
AND ANTENNA
RF OUT
PA2 OUT
PA1 OUT
2-WAY
COMBINER
VV
COUPLERDIRECTIONAL
U2
Bandpass Filter
TAV-1000 Combiner Enclosure Block Diagram
Date: December 17, 2003 Page: 1 of 1
Rev ID
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III-
8
Specifications
The following specifications were taken with a Technalogix modulator/processor. Should a different modulator or
processor be used, specifications could vary. For this reason, we recommend that any different
modulator/processor be shipped to Technalogix so the system can be matched and set up optimally. In
addition, the audio/video ratio the input to the power amplifier needs to be –10 dB in order for the software and
LCD readout to be accurate. All specifications below were taken with the audio/video ratio set -10dB.
RF Characteristics
Frequency range any specified VHF Channel 2 to 13
Frequency Response (one channel) ±0.5 dB
Frequency Stability ±250 Hz
Selectivity 60 dB (adjacent channel)
Minimum Input Level 0 dBmV
Rated Visual Output Power 1000 Watts
Rated Aural Output Power 10% of peak visual power
IF Output Level -12 dBm nominal
Input Impedance 75 Ohms
Output Impedance 50 Ohms
Harmonics > 60 dB below rated power
Predominant Intermodulation Distortion dBc = decibels below visual carrier
+ 920 kHz > -53 dBc
- 920 kHz > -53 dBc
+ 2.66 MHz > -53 dBc
- 2.66 MHz > -53 dBc
+ 5.42 MHz > -53 dBc
+ 7.16 MHz > -53 dBc
3rd Order Intermodulation Distortion
- 4.5 MHz > -60 dBc
+ 9.0 MHz > -60 dBc
All others > -60 dBc
Spurious Emissions > -60 dBc
NTSC Video Characteristics
Input Level to modulator (for 87.5% modulation) 1.0 VPP (100IRE + 40IRE sync)
Differential Phase (at 87.5% modulation) ±2 Degrees
Differential Gain (at 87.5% modulation) 2%
Group Delay < ±40 nS
Video Group Delay Pre-emphasis Conforms to IC/FCC specifications
K-Factor 1.9% for 2T Pulse
Hum and Noise > 60 dB below rated power
Aural Characteristics
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III-
9
Input Level for 25 kHz Deviation 0.3 VPP
Frequency Response (Standard Pre-emphasis) ±1 dB
Harmonic Distortion (25 kHz Deviation) < 1% 50 Hz to 15 kHz
Amplitude Modulation Noise > 50 dB
Frequency Modulation Noise > 60 dB
Intercarrier Stability ±250 Hz
Physical Characteristics
Power Requirements
Power Supply 230 VAC, 30 AAC
Combiner / Filter 115 VAC, 2 AAC
Operating Temperature Range 0°C to 50°C
Dimensions
TAV-500 Power Amplifier (each) W-19" flange (17” encl.) , D-25", H-8 3/4” (5U)
Combiner / Filter W-19" flange (17” encl.) , D-25", H-8 3/4” (5U)
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IV-1
Section IV – RF Components
Amplifier Pallets
The PA25-VHF pallet is a two stage ultra linear class-A linear pallet. The PA25-VHF-L has a typical gain of
40dB and the PA25-VHF-H has a typical gain of 34dB. These pallets draw no more than 3.0Adc total drain
current (the exact bias and drain currents of your system are found in the spec sheet supplied with each
manual). The quiescent and drain currents can be measured on the PA25-VHF pallet by measuring the voltage
drop across the current sense resistor found directly at the DC power supply lead input to the pallet. This
resistance is 0.01-ohms, providing a 10mV per ampere ratio.
The final amplifier stages are comprised of (2) P400-VHF-L or P400-VHF-H amplifier pallets and are each
characterized with minimum gains of 18 dB (low band) or 15 dB (high band) and maximum drain currents of
28 A (low-band) or 20 A (high-band).
All currents on the driver and final stages can be measured across the on-board shunt resistor (0.01-ohm)
found at the DC supply inputs. With this resistance, a 1mV reading across this resistor indicates a current
draw of 1.0A.
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TECHNALOGIX LTD.
25 W VHF HI BAND DRIVER
P25-VHF-H
R.S. MCDONALD
14 SEPTEMBER, 2000
A
A
1
1
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Technalogix Ltd.
400 Watt High Band VHF Pallet
P400-VHF-H
R.S. McDonald
July 30, 2001
B
A
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IV-4
Power Divider/Combiner (internal to each TAV-500 enclosure)
A Wilkinson power divider and combiner (identical printed circuit boards) are used to split the RF signal into, and
combine the amplified RF signal out of the (2) P400-VHF final amplifier pallets. Flanged power resistors help
ensure that any differences between the inputs or outputs is balanced.
The Wilkinson design takes advantage of the fact that an impedance transformation can take place across a
quarter-wavelength transmission line if the line has a different impedance than the source or load impedances
being matched. In this case, quarter-wavelengths of 75-ohm coaxial are used to maintain 50-ohm impedances at
the input and output of the Wilkinson divider/combiner. Due to its electrical and mechanical symmetry, the
Wilkinson design’s performance over moderate bandwidths is superior to other types. This design maintains
phase and amplitude equality, in addition to providing isolation and matched outputs.
Isolator
The power amplifier pallets are protected in part by the isolator located in the filter enclosure. It is actually made
up of a circulator and 50-ohm dump resistor. The circulators’ specifications include an insertion loss of less than
0.2dB with an isolation rating better than 20dB. Any reflected power gets dumped into the flanged power
resistor. Even though the flanged power resistor is rated for only 250-watts, and there could potentially be 500-
watts being reflected back into the circulator, the software will recognize quickly that reflected power is present
and turn the carrier off. This way, there is instantaneous protection due to the isolator setup and long term
protection due to the software.
Final Combiner (internal to combiner enclosure)
The RF outputs from the (2) TAV-500 amplifier modules then pass into a final enclosure where the signals are
combined, then filtered and monitored once again. The combiner is a 2-way, 1000-watt isolated power combiner
with a maximum phase imbalance of +/-1 degree. Minimum isolation is -18 dB and maximum insertion loss is -
0.45 dB from 170 to 280 MHz. Minimum return loss from ports 1 to 2 (input to input) is -25 dB and -20 dB on
port 3 (output).
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IV-5
Directional Coupler (internal to TAV-500 and combiner enclosures)
The Technalogix dual directional couplers provide DC voltages proportional to forward and reflected RF power
monitoring. These analog voltages are converted for processing using a 10-bit analog-to-digital converter and
provide the control system with valuable data for monitoring purposes. The directional couplers installed in the
power amplifier and filter enclosures have peak detection circuits on the forward RF power side of the coupler
and average detection circuits on the reflected RF power side of the coupler. This is to allow the end user to
set power in a manner that is more independent of modulation and closer to a true tip-of-sync meter. Hence, the
readings on the displays in the power amplifier system are peak for forward and average for reflected. Output
power should be set by the following procedure:
THE POWER OUTPUT SHOULD NEVER BE ADJUSTED EXCEPT
UNDER THE TEST CONDITIONS OF NO AURAL CARRIER, WITH THE
VISUAL CARRIER MODULATED WITH SYNC AND BLANKING.
The directional coupler has a typical insertion loss of 0.05dB and its Type N connectors can handle 1,500 watts
peak. The coupler requires 8 to 8.5Vdc to power the internal electronics of the coupler and is supplied from the
control printed circuit board at the front of each enclosure.
Filter
The passive bandpass filter rejects spurious and harmonic output products and passes the VHF channel RF
output. The cavity resonator uses aperture coupling and is a linear resonator design. Typical insertion loss is 0.6
dB to 1.0 dB depending on channel frequency. Average roll off is –33 dBc at a point 4.5 MHz below the peak
visual carrier frequency and –30 dBc 9.0 MHz above the peak visual carrier frequency. The filter is DC grounded
on both the input and output for additional lightning protection.
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V-
1
Section V – Power Supply
Switching AC-DC power supplies are used to power the amplifier pallets, the control circuits, and all of the fans.
There is one power supply located in each power amplifier enclosure to generate the necessary current for the
amplifier pallets. These (2) supplies are set at 31.0 Vdc nominally. All fans run off this same supply, though they
pass through a series dropping resistor to lower the supply voltage, as the fans are 24Vdc.
A 24Vdc nominal power supply is located in the combiner enclosure. It simply supplies power to the control
PCB and the cooling fan.
The power supplies in the power amplifier enclosure are Mean Well PSP-1500. The power supply found in the
filter enclosure is a Mean Well S60-24. The switching power supplies are fully protected against short circuit and
output overload. Short circuit protection is a cycling type power limit. The internal AC fuse is designed to blow
only on a catastrophic failure in the unit – the fuse does not blow on overload or short circuit. The thermal
shutdown automatically recovers when the power supply chassis cools down.
AC (220Vac) is fed into each power amplifier enclosure via a filtered EMI AC entry and then through a resettable
circuit breaker. The AC for the combiner enclosure (110Vac) is also fed through a filtered EMI AC entry. It is
then current limited with a resettable circuit breaker before passing through a rocker switch. This switch turns
the AC on and off to the switching power supply.
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MEAN WELL
SWITCHING POWER SUPPLY
ISO-9001 CERTIFIED MANUFACTURER
PSP-1500
SERIES
.LOW COST, HIGH RELIABILITY .100% FULL LOAD BURN-IN TEST
.BUILT IN EMI FILTER, CURRENT SHARING CIRCUIT .105ºC OUTPUT CAPACITOR
.BUILT IN REMOTE CONTROL, REMOTE SENSE, .BUILT IN PFC CIRCUIT PFC>=0.95,
POWER GOOD SIGNAL COMPLIES WITH EN61000-3-2
.SHORT CIRCUIT, OVERLOAD, OVER VOLTAGE, OVER TEMP. PROTECTED
MODEL
SPECIFICATION PSP-1500
-5PSP-1500
-12 PSP-1500
-13.5 PSP-1500
-15 PSP-1500
-24 PSP-1500
-27 PSP-1500
-48
DC OUTPUT VOLTAGE 5V 12V 13.5V 15V 24V 27V 48V
OUTPUT V. TOLERANCE ±2% ±1% ±1% ±1% ±1% ±1% ±1%
OUTPUT RATED CURRENT 217.5A 112.5A 100.5A 90A 56.4A 50.4A 28.5A
OUTPUT CURRENT RANGE 0-217.5A 0-112.5A 0-100.5A 0-90A 0-56.4A 0-50.4A 0-28.5A
RIPPLE & NOISE 200mVp-p200mVp-p200mVp-p200mVp-p200mVp-p200mVp-p200mVp-p
LINE REGULATION ±1% ±0.5% ±0.5% ±0.5% ±0.5% ±0.5% ±0.5%
LOAD REGULATION ±2% ±1% ±1% ±1% ±1% ±1% ±1%
DC OUTPUT POWER 1087.5W 1350W 1356.75W 1350W 1353.6W 1360.8W 1368W
PEAK OUTPUT POWER 1200W 1500W 1500W 1500W 1500W 1500W 1500W
EFFICIENCY 76% 82% 82% 82% 84% 84% 86%
DC VOLTAGE ADJ. 4.75-5.5V 10-13.2V 12-15V 13.5-18V 20-26.4V 24-30V 41-56V
INPUT VOLTAGE RANGE 90~264VAC 47~63Hz; 127~370VDC
AC CURRENT 10.5A/230V
POWER FACTOR 0.95/230VAC
INRUSH CURRENT 100A/230V
LEAKAGE CURRENT <3.5mA/240VAC
OVERLOAD PROTECTION 115%~140% TYPE:CONSTANT CURRENT LIMITING RESET:AUTO RECOVERY
OVER VOLTAGE PROTECTION 5.75~6.75 13.8~16.2V 15.5~18.2V 18~21V 27.6~32.4V 31~36.5V 57.6~67.2V
OVER TEMP.PROTECTION RTH2>=95ºC OUTPUT SHUTDOWN
REMOTE CONTROL RC+/RC-: 0~0.8V=POWER ON; 4~10V=POWER OFF SINK CURRENT 4~10mA
TEMP. COEFFICIENT ±0.03% / ºC (0~50ºC)
SETUP, RISE, HOLD UP TIME 1.5s, 50ms, 15ms
VIBRATION 10~500Hz, 2G 10min./1cycle, PERIOD FOR 60min. EACH AXES
WITHSTAND VOLTAGE I/P-O/P:3KVAC I/P-FG:1.5KVAC O/P-FG:0.5KVAC
ISOLATION RESISTANCE I/P-O/P, I/P-FG, O/P-FG:500VDC / 100M Ohms
WORKING TEMP., HUMIDITY -10ºC~+60ºC(REFER TO OUTPUT DERATING CURVE), 20%~90% RH
STORAGE TEMP., HUMIDITY -20ºC~+85ºC, 10%~95% RH
DIMENSION 278*129*190.5mm
WEIGHT 6.9 Kgs
SAFETY STANDARDS MEET UL1950
EMC STANDARDS MEET CISPR22, EN61000-3-2, EN61000-4-2,3,4,5,6,8,11
NOTE : 1.ALL PARAMETERS ARE SPECIFIED AT 230VAC INPUT, RATED LOAD, 25ºC 70% RH. AMBIENT.
2.TOLERANCE GINCLUDE SET UP TOLERANCE, LINE REGULATION, LOAD REGULATION.
3.RIPPLE & NOISE ARE MEASURED AT 20MHz BY USING A 12" TWISTED PAIR TERMINATED WITH A 0.1uF & 47uF CAPACITOR.
4.LINE REGULATION IS MEASURED FROM LOW LINE TO HIGH LINE AT RATED LOAD.
5.LOAD REGULATION IS MEASURED FROM 0% TO 100% RATED LOAD.
6.REFER TO OUTPUT DERATING CURVE VS INPUT VOLTAGE.
7.PEAK OUTPUT POWER LASTING <30 SECONDS WITH A MAX. 10% DUTY CYCLE. 2002-01-28
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VI-
1
Section VI – Monitor and Control System
Control Board Overview (Series IIH)
The control printed circuit boards (PCB) are located at the front of each enclosure connected directly to the back
of the liquid crystal displays (LCD) and are identified as Series IIH PCBs. The main purpose of the Series IIH
PCB is to monitor the RF power and the DC supply voltages in the power amplifier and filter enclosures and to
monitor the DC supply voltages in the power supply enclosure. In all cases, a DC voltage proportional to the
parameter being sampled is conditioned, protected, buffered, and then run into an analog-to-digital converter
(ADC) where software processes the signal. The software processing determines if the parameters are within the
predetermined safe operating levels and displays the parameters on the LCD for monitoring purposes. The
Series IIH PCB can be broken apart into (5) main component areas: the power supply, interface, signal
processing, display, and microcontroller. Schematics are found later in this section.
Power Supply Components
There are (4) power supply voltages generated on the Series IIH PCB:
1. +5Vdc for all logic and general purpose PCB supply voltage.
2. +4Vdc for the LED backlighting on the LCD
3. -4Vdc for the contrast voltage required by the LCD
4. +8Vdc for the directional coupler supply
The +5Vdc is generated from a small switching power supply comprised of C1, C2, D2, L1, and U1. This power
supply accepts DC input voltages up to 40Vdc and outputs +5Vdc at 1Adc. This voltage is always on, as the
ON/OFF pin on U1 is hard-wired to the ‘on’ configuration.
The +4Vdc is generated from a small switching power supply comprised of components C3, C4, D3, L2, and U2.
This power supply accepts DC input voltages up to 40Vdc and outputs +5Vdc at 1Adc. The voltage is then
dropped to +4Vdc through R1. This backlight voltage can be turned on and off via the ON/OFF pin on U2. The
PCB is setup in a manner that allows this voltage to be hard-wired ‘on’ all the time or controlled from the
microcontroller through latch U11. This selection is made with jumper J2.
The -4Vdc is generated using a switched capacitor voltage converter design, using components C6, C7, R2, R3,
U4, and VR1. U4 accepts +5Vdc from the general purpose +5Vdc supply and generates -4Vdc. This voltage is
then dropped across the voltage divider (R2, R3) to generate the contrast voltage specific to the LCD in the
system.
The +8Vdc required by the directional coupler is generated with a standard linear voltage regulator, U3. C5
cleans up any ripple or noise that might be on the output voltage.
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VI-
2
Interface Components
The interface section of the Series IIH PCB includes the front panel switch interfacing in addition to the
buzzer and carrier disable output circuits.
The (4) momentary switches found on the front panels of each enclosure are tied to the microcontroller
through an isolation stage to avoid any static discharge or noise on the switch wiring from reaching the
microcontroller. Optoisolators U5 and U6, in addition to R4…R15 create the necessary isolation for the
sensitive microcontroller. By depressing any momentary switch, a ground (0V) is applied to the input of the
optoisolators. The optoisolators will, in turn, output a ground (0V) to the microcontroller.
The membrane tactile switches found on the front panels of the enclosures operate in the following manner
with a depress:
POWER – When unit is plugged in, AC is supplied to the fan and switching power supply input, but the
amplifiers are still turned off. In order to turn the amplifiers on, wait ten seconds after plugging the PA in
and push in the “POWER” tactile button. The LCD will read “Soft Start Warm Up, Please Wait”. After
ten seconds the bias voltages will be turned on and you may then plug in the RF drive. Depress for (1)
second to turn on and (3) seconds to turn system off. In the case of multiple enclosures, all POWER
switches are tied together in each enclosure, so only one needs to be depressed.
NAVIGATE – Turns on backlight to LCD and displays forward and reflected RF power and DC supply
voltage parameters. When power amplifier is first turned on, the LCD comes on automatically and this
information is displayed. Information is displayed for approximately 2 minutes before the backlight turns off
and the display is cleared. This is set up so as not to burn any pixels into the LCD from extended on
time. In the case of multiple enclosures, the NAVIGATE switches are individual to each enclosure.
SELECT – Turns on backlight to LCD and displays forward and reflected RF power and DC supply
voltage parameters. When power amplifier is first turned on, the LCD comes on automatically and this
information is displayed. Information is displayed for approximately 2 minutes before the backlight turns off
and the display is cleared. This is set up so as not to burn any pixels into the LCD from extended on
time. In the case of multiple enclosures, the SELECT switches are individual to each enclosure.
RESET – Tactile pushbutton resets the monitor and control system. The amplifier gets shut down for
under 0.5 seconds and comes back on with each depress of the reset button. At the same time, all fault
counters in the microcontroller software are reset and the LCD is reset in the same manner as it is with a
depress of the NAVIGATE button. Reset switches are individual to each enclosure but may be tied
together externally through the remote port, as explained later in this section.
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VI-
3
The buzzer control comes from pin 5 on microcontroller U14. The control signal turns on the base of
transistor Q1, which allows current to flow through the single tone magnetic buzzer. Jumper J4 simply turns
off the buzzer.
The carrier disable circuit simply applies a shutdown voltage to the driver pallet in the system. The U14
generates the signal out of pin 21 and controls relay Q2 through R17. When Q2 is turned off, the shutdown
voltage to the driver is floating and the carrier is on. During a fault condition, when Q2 is turned on, the
shutdown voltage is applied to the carrier disable on the driver.
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VI-
4
Signal Conditioning Components
The signal processing section of the Series IIH PCBs is used to buffer potentially noisy or damaging signals
from the ADC. Power supply voltages and forward and reflected power samples from a directional coupler
are then digitized.
Firstly, all analog signals are protected with a resettable fuse and transient voltage suppressor (TVS)
combination. These components ensure that voltages above the Vbr breakdown voltage of the TVS get
clamped and do not pass farther down the circuit. After this protection stage, the analog voltages are
dropped with voltage dividers to safe levels for the buffers and ADC. For example, a 28Vdc power supply
sample is dropped to a level below the +5Vdc supply voltage of the ADC. After the voltage dividers, the
analog signals are buffered with U7 and U8, configured as unity gain voltage followers. Finally, after some
further decoupling capacitors and filters, the analog signals get digitized by the 8-channel, 10-bit ADC (U10)
and sent to the microcontroller through a serial interface.
In the power amplifier and filter enclosures, there are (3) analog voltages that are conditioned and processed:
DC power supply sample, forward RF power, and reflected RF power. Specifically, the components for the
power amplifier and filter enclosure conditioning are as follows:
DC power supply sample – J7 (pin8), F9, D11, R32, R33, U8, C33, C34, C35, and U10.
Forward RF power – J7 (pin7), F8, D10, R30, R31, U8, C29, C30, C31, and U10.
Reflected RF power – J7 (pin6), F7, D9, R28, R29, U8, C26, C27, C28, AND U10.
In the power supply enclosure, there are (2) power supplies paralleled together. Hence, only (1) analog
voltage is conditioned and processed for the LCD. Specifically, the components for the power supply sample
are as follows:
DC power supply sample- J7 (pin8), F9, D11, R32, R33, U8, C33, C34, C35, and U10.
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VI-
5
Display Components
The display section of the Series IIH PCB is comprised of the LCD and the components that make up the
data bus which send the data from the microcontroller to the LCD.
Specifically, the LCD is an alphanumeric 20X4 display that uses the industry standard 44780 controller and
a parallel interface for data communications. The microcontroller sends out the data to be displayed via a
serial bus, where the signals are latched with U11 and U12 and converted to a parallel data stream. The
parallel data then transfers directly to the LCD through connector J8. J8 also carriers the power supply for
the LCD.
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VI-
6
Microcontroller Components
The heart of the monitor and control system found in Series IIH PCBs is microcontroller U14. This
microcontroller analyzes all RF power levels and voltages to ensure that all operating parameters are within
their predetermined safe operating levels. If a fault is found, appropriate action is taken to help protect the
system from damage, which may include turning the RF carriers off. A full description of all faults and their
respective actions is found later in this section.
The power supply for the microcontroller is monitored closely via supervisor U13. Should the +5Vdc supply
drop below +4.5Vdc, a microcontroller reset is generated to ensure there are no brown out conditions that
may latch up the microcontroller up to an unknown state. The front panel Reset momentary switch is also
tied to this line after optoisolation. The microcontroller’s clock source (4.000MHz) is generated by ceramic
resonator CR1. If the software is running, LED D12 will be lit. Finally, U15 stores all characters for the LCD
to minimize the overhead required for the microcontroller, and also stores the current state of the power
ON/OFF of the system. This ensures that, in the event of a power outage, the system returns to the exact
state is was before power was interrupted.
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VI-
7
Fault Shutdowns
On the LCD (Liquid Crystal Display) the following messages may appear:
If you see this message, the system will:
- shut amp down for 1 minute
- automatically turn amp on after 1 minute and check again for overdriven amplifier
- come back to the same power level that it was set
If you see this message, the system will:
- shut amp down for 5 minutes
- automatically turn amp on after 5 minutes and check again for high VSWR
- come back to the same power level that it was set
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VI-
8
Enclosure Interfacing
In the event of a fault in the combiner/filter enclosure, for example high reflected power or overdriven output
levels, the power amplifier enclosures need to know that there is a fault. A DB9 cable accomplishes this by
sending a fault signal from the combiner/filter enclosure to indicate to the power amplifier enclosure that
action may need to be taken. Specifically, the shutdown circuitry on the combiner/filter enclosure’s control
PCB sends a ground signal through the DB9 to one of the optoisolated inputs on the power amplifier’s
control PCB. The power amplifier control PCB, in turn, then sends its shutdown voltage out to disable the
driver and turn off the carrier.
Remote Port
The remote port allows external control of the transmission system via the DB25 connector on each
enclosure. All functions on the remote port are simply hard-wired or paralleled to existing wiring to provide a
secondary method of control to the user, and are activated as follows:
pin 1: ground to reset microcontroller, float otherwise
pin 2: ground for 2 seconds to toggle carrier on/off, float otherwise
pin 3: common ground
pin 4: DC power supply sample
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Series II - Bill of Materials
H
20-Aug-04
Item Qty Components Description Tolerance Package Equivalency
1 1 BZ1 BUZZER, magnetic, 5V, single tone Through hole
Challenge Electronics TDB05; Global Components
TDB05, Tranducers USA TRIE-1205P
2 2
C1 (solder side), C5
(solder side) CAPACITOR, electrolytic, 100uF, 63V <=20% SMT (Panasonic VS "G" size)
Panasonic ECE-V1JA101P, NIC
NACEW101M63V10x10.5
3 2
C2 (electrolytic), C6
(solder side) CAPACITOR, electrolytic, 330uF, 35V <=20% SMT (Panasonic VS "G" size)
Panasonic ECE-V1VA331P, NIC
NACEW331M35V10x10.5
4 22
C1 (0805 comp. side),
C2 (0805 near U8), C3
(0805 PSU filter), C4
(0805 near buzzer), C4
(0805 RFL I/P), C5
(0805 comp. side), C6
(comp. side), C7 (0805
near FWD I/P), C8
(0805 near U8), C9
(solder side), C10
(solder side), C11, C12,
C13, C14, C15, C16,
C17, C18 (0805 beside
uPC), C19, C20, C21 CAPACITOR, ceramic, 0.01uF, 63V <=20% SMT 0805
5 7
C7 (1206 near pow.
conn.), C10 (1206
solder side), C45, C46,
C47, C48, C49 CAPACITOR, ceramic, 0.1uF, 25V <=20% SMT 1206 Utech GMC31X7R104K50NT
6 2
C8 (electrolytic), C9
(electrolytic comp. side) CAPACITOR, electrolytic, 100uF, 25V <=20% SMT (Panasonic VS "E" size) Panasonic ECE-V1EA101UP
7 2
C15, C18 (1210
tantalum) CAPACITOR, tantalum, 1uF, 16V <=20% SMT 3216 KOA TMC1CA105KLRH
8 5
C25, C28, C31, C34, C3
(electrolytic) CAPACITOR, electrolytic, 1uF, 16V <=20% Through hole, radial, 5mm diameter
Nichicon LB/VX/USA/SA; Panasonic KA/KS/SU;
Sprague 501D/513D
9 1 CR1
CLOCK, ceramic resonator, 4.000 MHz,
w/caps
f <= 0.5%
C <= 20% Through hole, 3-position, 0.1" spacing ECS Inc. ZTT-4.00MG
10 1 D1
DIODE, TVS, 600 watts, Vwm=30V, Vbr
min=33.3 (for TV power amplifier) SMB Crydom SMBJ30A; GI SMBJ30A
11 1 D1
DIODE, TVS, 600 watts, Vwm=48V, Vbr
min=53.3 (for FM power amplifier) SMB Crydom SMBJ48A; GI SMBJ48A
12 2
D2,D3
DIODE, schottky, If=3A, Vr=60V SMC International Rectifier 30BQ060
13 1 D4 DIODE, rectifier, If=1A, Vr=400V DO-41
Micro Commercial 1N4004, ON Semiconductor
1N4004RL, General Semiconductor 1N4004
14 2 D9, D10
DIODE, TVS, 600 watts, Vwm=5.0V, Vbr
min=6.4 SMB Crydom SMBJ5.0A; GI SMBJ5.0A
15 1
D12
DIODE, LED, RED, clear or diffused SMT 1206 Lumex SML-LX1206IW
16 1 F1
FUSE, resettable, Ihold=0.75A, Itrip=1.5A,
Vmax=72V 0.23" lead spacing, 20AWG leads Raychem RXE075; Bourns MF-R075
17 3 F6, F7, F8
FUSE, resettable, Ihold=0.14A,
Itrip=0.34A, Vmax=60V miniSMD Raychem miniSMDC014-2
18 1 J1
CONNECTOR, 4-position plug, 180
degree wire entry, 90 degree screw
access, 5.08mm -Wieland 25.340.3453, Weco 10.808.104
19 1 J1
CONNECTOR, 4-position header,
pluggable, vertical, closed, 5.08mm Through hole, 0.2" spacing Wieland 25.350.3453, Weco 20.806.128
20 3 J2, J5, J6
CONNECTOR, breakaway header strip, 3-
and 2-position required Through hole, 0.1" spacing Molex 22-28-4300; Samtec TSW-130-05-T-S
21 3
J2, J5, J6
CONNECTOR, 2-position post shunts
0.1" spacing
AMP 382811-6; Samtec SNT-100-BK-T
22 1 J3
CONNECTOR, 5-position plug, 90 degree
wire entry, 180 degree screw access,
5.08mm -Wieland 25.346.3553
23 1 J3
CONNECTOR, 5-position header,
pluggable, rt. angle, closed, 5.08mm Through hole, 0.2" spacing Wieland 25.352.3553, Weco 10.806.129
24 1 J4
CONNECTOR, 5-position, header, 0.1"
spacing, 0.025" square post Through hole, 0.1" spacing (SIP5)
25 2 J7, J8
CONNECTOR, 3-position plug, 180
degree wire entry, 90 degree screw
access, 5.08mm -Wieland 25.340.3353, Weco 10.808.103
26 2 J7, J8
CONNECTOR, 3-position header,
pluggable, vertical, closed, 5.08mm Through hole, 0.2" spacing Wieland 25.350.3353, Weco 20.806.127
27 1
J9
CONNECTOR, terminal strip, 16-position Through hole, 0.1" spacing Samtec TSW-116-18-T-S
28 1
J9
CONNECTOR, socket strip, 16-position Through hole, 0.1" spacing Samtec SSW-116-03-T-S
29 1 L1
INDUCTOR, 680uH, Irms=0.4A,
DCR=2.02 ohms SMT JW Miller 3316-681M
30 11
L2, L4, L5, L6, L7, L8,
L9, L10, L11, L12, L13
INDUCTOR, 0.01uH, Imax=0.45A,
DCR=0.13 omhs +/- 10% SMT 1210 KOA KL32TE010K
31 1 L3
INDUCTOR, 680uH, Irms=1.3A, DCR=0.2
ohms SMT (Talema S5) Talema SWS-0.85-680
32 1 LCD1
20 X 4 character liquid crystal display,
LED backlit 4-40 pem mount (4) Varitronix 20464K
33 1 PCB1
Series II, revision H printed circuit board,
soldermask, silkscreen, FR4 Alberta Printed Circuits, MPC, GRM, Enigma, …
34 2 Q1, Q2 TRANSISTOR, NPN, Ic=1A, Vce=40V SMT SOT-23
Fairchild MMBT2222A; Zetex FMMT2222A; Diodes
Inc MMBT2222A-7
35 1 R1 RESISTOR, 4.7 ohm, 1/4 watt, carbon film 5% Through hole, axial 0.4 Yageo CRF-25JB-4R7
36 1 R2
RESISTOR, 15.0 ohm, 1/10 watt, thick
film 1% SMD 0805 Panasonic ERJ-6ENF15R0V
37 1 R3
RESISTOR, 75.0 ohm, 1/10 watt, thick
film 1% SMD 0805 Panasonic ERJ-6ENF75R0V
38 12
R4, R5, R6, R7, R10,
R11, R12, R13, R16,
R32, R34, R36
RESISTOR, 1.00 kohm, 1/10 watt, thick
film 1% SMD 0805 Panasonic ERJ-6ENF1001V
39 4 R8, R9, R14, R15
RESISTOR, 10.0 kohm, 1/10 watt, thick
film 1% SMD 0805 Panasonic ERJ-6ENF1002V
revision:
date:
Optional part depending on power level of TV or FM
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Series II - Bill of Materials
H
20-Aug-04
40 1 R17
RESISTOR, 4.99 kohm, 1/10 watt, thick
film 1% SMD 0805 Panasonic ERJ-6ENF4991V
41 1 R26 (next to VR2)
RESISTOR, 2.7 KOHM, 1/10 watt, thick
film 1% SMD 0805
42 1 R26 (next to VR2)
RESISTOR, 680 OHM, 1/10 watt, thick
film 1% SMD 0805
44 1 R31
RESISTOR, 37.4 kohm, 1/10 watt, thick
film (for TV PA >= 250W) 1% SMD 0805 Panasonic ERJ-6ENF3742V
45 1 R31
RESISTOR, 15 kohm, 1/10 watt, thick
film (for FM amplifier) 1% SMD 0805 Panasonic ERJ-6ENF4991V
46 2 R28, R30
RESISTOR, 121 kohm, 1/10 watt, thick
film 1% SMD 0805 Panasonic ERJ-6ENF1213V
47 1
R33
RES, 120 ohm, 1/10 watt, thick film 1% SMD 0805 Panasonic ERJ-6ENF1200V
48 1 RLY1
RELAY, SPDT, 5Vdc contact,
5A@30Vdc/10A@125Vac contact Aromat JS1-5V; P&B T7CS5D-05
49 1 U1
REGULATOR, switching, 5Vdc, 3A,
fosc=52kHz SMD TO-263-5 National LM2576HVS-5.0
50 1 U2
REGULATOR, switching, 5Vdc, 1A,
fosc=150kHz Through hole TO-220-5 National LM2595T-5.0
51 1
U3
REGULATOR, linear, 8V, 1A Through hole TO-220 7808CT
52 1 U4 REGULATOR, inverter, 100mA SMD SOIC-8
National LM2660M; Analog Devices ADM8660,
Maxxim MAX660
53 2 U5, U6
OPTOISOLATOR, dual, Viso=2500V,
Vce=30V Through hole, DIP-8 Fairchild MCT6
54 1
U8
OP AMP, quad, low voltage
SMD SOIC-14 National LMV324M
56 1 U9
REFERENCE, 2.50V (for TV PA >=
250Wpk) +/-0.2% SMD SOT-23 National LM4040BIM3-2.5
57 1
U10
ADC, 10-bit, 10-channel
SMD SOIC-16 Analog Devices AD7812YR
58 2 U11, U12 LOGIC, 8-bit shift register with latches SMD SOIC-14
Fairchild MM74HC595M; On Semi MC74HC595AD;
Phillips 74HC595D
59 1 U13
SUPERVISOR, n-channel, open drain,
internal pullup resistor SMD SOT-23 MCP130T-450I
60 1 U14
MICROCONTROLLER, OTP, 4k, 22 I/O
lines Through hole DIP-28 Microchip PIC16C63A-04/SP
61 1
U15
MEMORY, 8k X 8, EEPROM, SPI
SMD SOIC-8
Microchip 25LC640I/SN
62
3
VR2, VR3, VR4
RES, variable, 2 kohm, 11 turn
date:
revision: Optional part depending on power level of TV or FM
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SOLDER SIDE
SOLDER SIDE
COMPONENT SIDE
BK LT
CTRL
SELECT
1
SERIES II, REV. H - Control System
SOLDER SIDE
Vin Cond
NEAR BUZZER
C4
0805 CHIP
C14
L5
VR1
+
ELECTROLYTIC
C8
+
ELECTROLYTIC
C9
P1
P2
P3
P4P5
P6
P7
P8
U4
BkLtCtrl
GND
+8V OUT
GND
Vin L1
D2
+
ELECTROLYTIC
C1
D1
F1
3
J1 1Vin
2
Vout
4
Feedbk
3Gnd
5On/Off
U1
+
ELECTROLYTIC
C2
+5Vdc
4
J1
+
ELECTROLYTIC
C5
+
ELECTROLYTIC
C6
2Vin
1
Vout
4
Feedbk
3Gnd
5On/Off
U2
D3
COMPONENT SIDE
L3
Pin15LCD
IN
COM
OUT
U3
NEAR POW. CONN.
C7
1206 CHIP
1
J1
J1
2
+5Vdc
Pin3LCD
J2
R3
R2
R1
A. Sivacoe
SERIES II: Control System
H Power Supply Section
Date: May 14, 2004 Page: 1 of 1
Rev ID
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SERIES II, REV. H - Control System
2
Buzzer
delete
D4
J4 3
J4 5
SEL In J4 4
J4 2
NAV In
J4 1
+5Vdc
J6
J3 5
Ground
J3 3
J3 4
J3 2
+5Vdc
+5Vdc
R4
R17
J7
2
Q2Rly.Ctrl
+5Vdc
RLY1
Rly. COM
Rly. N/O
Rly. N/C
J7
3
J7
1
Buzzer
J5
Q1
+5Vdc
R16
RES In
NC(RC6)
VW In
PWR In J3 1
P1
P2
P3
P4 P5
P6
P7
P8
U6
P1
P2
P3
P4 P5
P6
P7
P8
U5
R5 R6
R7
+5Vdc
R8 R9
VW uPC
PWR uPC
R13
R10 R11 R12
+5Vdc
R14 R15
PIN17uPC
RES uPC
BZ1
A. Sivacoe
SERIES II: Control System
H Interface Section
Date: March 5, 2004 Page: 1 of 1
Rev ID
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SIDE
3
For U7
SERIES II, REV. H - Control System
PSU
FWD
RFL
Low Threshold Adjust
NEAR
SIDE
uPC
VR4
VR3
C3
L2
C19
SOLDER SIDE
C9
0805 CHIP
SOLDER SIDE
C10
0805 CHIP
L1
Vin Cond
+
TANTALUM
C18
1210
+
C15
FWD I/P
C7
0805
COMP.
C5
0805
L6
L4
COMP.
C6
0805
RFL I/P
C4
0805
VR2
5
6
411
7
+
U8
2/4
3
2
411
1
+
U8
1/4
10
9
411
8
+
U8
3/4
12
13
411
14
+
U8
4/4
J8
1
Analog 1
J8 2
Analog 2
J8 3
Analog 3
Isoltd 4
Isoltd 3
Isoltd 2
Isoltd 1
BESIDE
C18
0805
F8
F7
F6
D9
D10
D11
C13
+5V
L11
D8
D7
D6
F3
F4
F5
SOLDER SIDE
C10
1206 CHIP
Isoltd 5
Isoltd 6
Isoltd 7
Isoltd 8
12
13
411
14
+
U7
4/4
J8
8
Analog 8
D5
F2
Analog 7 J8
7
Analog 6 J8
6
Analog 5 J8
5
9
10
411
8
+
U7
3/4
3
2
411
1
+
U7
1/4
5
6
411
7
+
U7
2/4
R26
R32
R31
R30
R29
R28
R27
R19
R18
R20
R21
R22
R23
R24
R25
A. Sivacoe
Series II: Control System
H Analog Input Section
Date: May 14, 2004 Page: 1 of 2
Rev ID
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SERIES II, REV. H - Control System
4
Pin 3 on U9 is left
unconnected on PCB
For U10
FWD
PSU
RFL
Low Thresh
C20
L8
C15
L9
NEAR U8
C8
0805 SOLDER SIDE
L3
1210 CHIP
C11
L7
C17
COMP. SIDE
C1
0805 CHIP
L10
2 1
U9
+5Vdc
C45
+
C42C41
+
C40C39
+
C38C37
+
C36C35
+
C34C21
+
C31C16
+
C28
NEAR U8
C2
0805
C12
+
C25
DtoUPC
DfromUPC
Dclk
ConvStrt
Isoltd 1
Isoltd 2
Isoltd 3
Isoltd 4
Isoltd 5
Isoltd 6
Isoltd 7
Isoltd 8
Vref
Cref
Vin1
AGND
Vin2
Vin3
Vin4
Vin5
Vin6
Vin7 Vin8
A0
DGND
TFS
RFS
Dout
Din
Dclk
ConvStart
Vdd
U10
R33
A. Sivacoe
Series II: Control System
H Analog Conversion Section
Date: May 14, 2004 Page: 1 of 1
Rev ID
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SERIES II, REV. H - Control System
5
U11: LCD control signals,
LCD backlight control, and
External interface outputs
U12: LCD data bus (D0...D7)
D0...D7 is text or instruction
serial_out
reset
shift_clk
latch_clk
output_en
serial_in
Qa(out_1)
Vcc Qb(out_2)
Qc(out_3)
Qd(out_4)
Qe(out_5)
Qf(out_6)
Qg(out_7)
Qh(out_7)
GND
U11
J10
5
J9
14
DfromUPC
Dclk
LCD D7
LCD D0
LCD D1
LCD D2
LCD D3
LCD D4
LCD D5
LCD D6
LCD E
LCD R/*W
LCD RS
J9
13 J9
12 J9
11 J9
10 J9
9J9
8J9
7
J9
4J9
5J9
6
LCD Vss
LCD Vdd
LCD Vo
J9
1J9
2J9
3
LED K
LED A
J9
15 J9
16
Unbuf D
Unbuf C
Unbuf B
Unbuf A
J10
4J10
3J10
2
Pin15LCD
BkLtCtrl
C46
+5Vdc
Latch1CS
Latch2CS
serial_out
reset
shift_clk
latch_clk
output_en
serial_in
Qa(out_1)
Vcc Qb(out_2)
Qc(out_3)
Qd(out_4)
Qe(out_5)
Qf(out_6)
Qg(out_7)
Qh(out_7)
GND
U12
Ext. PSU
J10
1Q3 uPCPIN14
Pin3LCD
R34
R35
A. Sivacoe
Series II: Control System
H LCD Section
Date: March 8, 2004 Page: 1 of 1
Rev ID
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6
SERIES II, REV. H - Control System
+
C50
C47
D12
Dclk
DtoUPC
Dig.In 3
Dig.In 2
Dig.In 1
C49
Buzzer
Latch2CS
Latch1CS
DfromUPC
Rly.Ctrl
Reset
Dig.Out2
CONVST
Dig.Out1
Vcc
C48
+5Vdc
MCLR/Vpp
RA0
RA1
RA2
RA3
RA4
RA5
Vss
OSC1/CLKin
OSC2/CLKout
RC0/T1CKI
RC1/CCP2
RC2/CCP1
RC3/SCK/CLRC4/SDI/SDA
RC5/SD0
RC6/TX/CK
RC7/RX/CK
Vss
Vdd
RB0/INT
RB1
RB2
RB3
RB4
RB5
RB6
RB7
U14
*CS
SO
*WP
Vss SI
SCK
*HOLD
Vcc
U15
Vcc
GND
Reset
U13
OSC1
OSC2
GND
CR1
R36
A. Sivacoe
Series II: Control System
H Microcontroller Section
Date: March 8, 2004 Page: 1 of 1
Rev ID
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VII-
1
Section VII – Mechanical Section
The heat sink allows the amplifiers to operate at a cooler temperature and prevents overheating, which helps
the longevity of the entire system. The heat sink has hollow fins, which help dissipate the heat from the
amplifiers faster than a conventional serrated or corrugated fin.
In addition to the cooling effects of the heat sink, within each 500-watt power amplifier enclosure, there are
four fans that each provide 170 cubic feet per minute (CFM) of air flow (into zero static pressure). There are
two fans mounted at the front of the heat sink and two mounted at the back end of the heat sink operated in
a push-pull configuration to assist with heat dissipation. The fans are a 24Vdc variety, so there are series
dropping resistors to drop the higher power supply voltage down to a safe level.
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Technalogix Ltd.
VIII-
1
Section VIII - Installation
This section contains unpacking, inspection, and installation instructions for the power amplifier. We are sure
that you are chomping at the bit to install your new system, so we recommend that you read the following
sections very carefully.
Building Recommendations
The quality of the building is of great importance if you are to expect long life and continued performance from
the power amplifier. The building must be clean, dry, temperature controlled and secure. Don’t forget to allow
space in the building for any additional racks to house test equipment, a workbench area, line regulating
transformers, ladders, equipment and parts storage, first aid kit, emergency generator if used, as well as heating
and cooling devices that may be unique to your installation. A sloping roof will tend to develop leaks less rapidly.
The building should be well roofed with good material. The cooling load will be lowered with reflective or light
colored roofing material.
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Technalogix Ltd.
VIII-
2
Heating and Cooling Requirements
The environment’s temperature will contribute greatly to the length of the power amplifier’s life. Refer to the
specifications in Section 3.0 for humidity and temperature specifications. Technalogix recommends that the
building’s filtered air intake must have capacity for all air-flow in the building plus an additional 20%. The TAV-
1000 uses (10) ball bearing fans – (4) for each power amplifier, (1) for the power supply enclosure, and (1) for the
combiner. Keep the intake below the roofline to avoid intake of solar heated air. Please ensure that the intake
and exhaust areas are on the same side of the building to avoid pressure differentials during windy conditions.
Also, do not position intake near exhaust’s preheated air. If air conditioning is required to cool the shelter,
discuss the situation with a qualified HVAC technician. Under average conditions, 12,000 BTUs will cool
approximately 500 square feet to a comfortable level.
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Technalogix Ltd.
VIII-
3
Electrical Service Recommendations
Technalogix recommends that a qualified, licensed local electrician be consulted for the required electrical
service. We suggest local electricians because:
• The personnel knows the local codes
• The personnel can be on site readily
• You are apt to get better overall support if you give what business you can to local suppliers
Technalogix recommends that proper AC line conditioning and surge suppression be provided on the primary AC
input to the power amplifier. All electrical service should be installed with your national electrical code in your
area, any applicable provincial or state codes, and good engineering practice. Special consideration should be
given to lightning protection of all systems in view of the vulnerability of most transmitter or translator sites to
lightning. Lightning arrestors are recommended in the service entrance. Straight and short grounds are
recommended. The electrical serviced must be well grounded. Do not connect the unit to an open delta primary
power supply, as voltage fluctuations could harm the unit. Branch your circuits. Do not allow your lights, your
workbench plugs, and your transmitting or translating equipment to operate on one circuit breaker. Each
transmitter or translator should have its own circuit breaker, so a failure in one does not shut off the whole
installation.
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Technalogix Ltd.
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4
Antenna and Tower Recommendations
Your preliminary engineering workgroup should establish your antenna and tower requirements, both for receiving
and transmitting antennas. Construction of sturdy, high quality antenna/tower systems will pay off in terms of
coverage of your service area, the overall quality and saleability of your radiated signal, and reduced
maintenance expenses. Technalogix provides complete turnkey antenna systems if needed. If your site is
serving as a translator, your receiving antenna should be in line of sight to the originating station all year round.
The foliage will change with season. Transmitting antennas can enhance or seriously impair the
transmitter/translator output.
The selection, routing, and length of coaxial cable are extremely important in the installation. If there is a 3 dB
line loss in the cable between your unit’s output and the transmitting antenna, a 1000-watt unit will only deliver
500 watts to the antenna. Buy the best cable you can obtain, route it via the shortest way to the antenna, and
keep it straight. Do not form it into sharp bends on its way. Do not use any more cable fittings for the installation
than absolutely necessary. All cautions here apply equally to all coaxial cables in the system - input and output.
Pay attention to radial ice accumulation when designing the transmission system. It is not uncommon for at
least an inch of ice to build up on the tower and antenna. This in turn significantly increases the weight, cross
section, and wind loading of the system.
Attaching the transmission line to the tower is crucial to maintain a safe and reliable operation. Nylon wire ties
and electrical tape will breakdown in the sunlight and ultimately fail, creating a potentially dangerous situation. It
is important to use proper clamps and hoisting grips and also ensure that the transmission line is grounded to
the tower in several locations. When high currents flow through the tower in the event of lightening strikes, some
of that current will flow through the outer conductors of the transmission lines. Due to the resistance difference
between the steel tower and copper transmission line, a significant voltage can be developed, often resulting in
arcing between the outer jacket and outer conductor, thus pitting the conductor.
• Preventative maintenance is crucial in ensuring that safety is maintained. Specifically, check that
transmission line grounds are tight and are not missing any hardware. Frequently inspect support
clamps or spring hangers. Consider investing in an ice break (ice bridge), if you haven’t already done
so, as shards of falling ice can damage the transmission line – and if it is going to happen, it will
happen at an important time. Check the tower light photocells and conduit.
The better-known tower manufacturers offer complete technical and safety documentation with their towers. Be
sure that you have this information as it regards wind loading, guying, etc. The best-designed antenna system
will function poorly if shortcuts and compromises are used during installation. Follow the manufacturer’s
instructions exactly, along with any engineering data prepared for the site. Be absolutely safe and certain about
this aspect as human lives may be at stake.
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Technalogix Ltd.
VIII-
5
Shelter Security
The FCC requires that the transmitter or translator be secure from entry or control by unauthorized persons, and
that any hazardous voltages or other dangers (including most tower bases) be protected by locks or fences as
necessary to protect personnel and prevent unauthorized tampering or operation. Security of the building further
implies that it be secure from wildlife. Use sturdy construction materials, including sheet metal if necessary.
Holes around conduit, cable, and other similar entry points should be stuffed with steel wool and caulked to
prevent entry of wildlife. Other features of security for your shelter may include its location with respect to the
prevailing wind conditions. A location leeward of some natural topographical feature will prevent wind damage
and snowdrifts. Check the soil runoff conditions that may slow or hasten wind or water erosion and other
concerns that may be unique to your location.
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Technalogix Ltd.
VIII-
6
Unpacking and Inspection
Check the outside of the container. Carefully open the container and remove the power amplifier. Retain all
packing material that can be reassembled in the event that the equipment must be returned to the factory.
Exercise care in handling equipment during inspection to prevent damage due to
rough or careless handling.
• Visually inspect the enclosure of the power amplifier for damage that may have occurred during shipment.
• Check for evidence of water damage, bent or warped chassis, loose screws or nuts, or extraneous
packing material in connectors or fan failures.
• Inspect all connectors for bent connector pins.
• If the equipment is damaged, a claim should be filed with the carrier once the extent of the damage is
assessed. Technalogix cannot stress too strongly the importance of immediate careful inspection of the
equipment and subsequent immediate filing of the necessary claims against the carrier if necessary.
• If possible, inspect the equipment in the presence of the delivery person. If the equipment is damaged, the
carrier is your first area of recourse.
• If the equipment is damaged and must be returned to the factory, phone for a return authorization.
• Claims for loss or damage may not be withheld from any payment to Technalogix, nor may any payment
due be withheld pending the outcome thereof. Technalogix cannot guarantee the carrier’s performance.
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Technalogix Ltd.
VIII-
7
Location and Function of Controls and Connectors (TAV-500 Power Amplifier)
The following illustration depicts the location of the connectors when installing each of the 500-watt power
amplifiers (TAV-500).
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Technalogix Ltd.
VIII-
8
POWER - Tactile button to turn carriers on and off. To turn off, must be depressed for at least
2 seconds. Tied internally through DB9 connectors to all other ON/OFF buttons.
NAVIGATE - Tactile button to refresh screen after two minute screen saver times out. All monitoring
and protection continues during screen saver.
SELECT- Tactile button to refresh screen after two minute screen saver times out. All monitoring
and protection continues during screen saver.
RESET - Momentary pushbutton to reset microcontroller in control board. Also clears existing
faults. Individual control board with reset comes back on with soft start feature.
RF IN – RF input from the output of the RF splitter. BNC connector, 50 Ω.
RF OUT – 500-watt RF output to be combined with the other 500-watt output. Connects to RF IN
PA 1 or 2 on combiner unit. N connector, 50 Ω.
PA CTRL – Control signals communicating with the combiner enclosure. Connects with the PA 1
and PA 2 CTRL connector on the combiner. DB9 connector (see Amplifier Monitoring
section for pinout description).
REMOTE PORT - pin 1: ground to reset microcontroller, float otherwise
pin 2: ground for 2 seconds to toggle carrier on/off, float otherwise
pin 3: common ground
pin 4: DC power supply sample
AC IN – AC input to switching power supply. Switching power supply draws a
maximum of 8 AAC at 220 VAC
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Technalogix Ltd.
VIII-
9
Location and Function of Controls and Connectors (Combiner / Filter Enclosure)
The following illustration depicts the location of the connectors when installing each of the 500-watt power
amplifiers (TAV-500).
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Technalogix Ltd.
VIII-10
POWER - Tactile button to turn carriers on and off. To turn off, must be depressed for at least 2
seconds. Tied internally through DB9 connectors to all other POWER buttons.
NAVIGATE - Tactile button to refresh screen after two minute screen saver times out. All monitoring
and protection continues during screen saver.
SELECT- Tactile button to refresh screen after two minute screen saver times out. All monitoring
and protection continues during screen saver
RESET - Tactile button to reset microcontroller in control board. Also clears existing faults.
Individual control board with reset comes back on with soft start feature.
PA1 and PA2 RF IN – RF input from the output of each power amplifier. N connector, 50 Ω.
RF OUT – 1,000-watt RF output to be connected with inline wattmeter and then to antenna. N
connector, 50 Ω.
PA CTRL – Control signals communicating from the combiner enclosure to the power amplifier
enclosures. Connects with the PA 1 and PA 2 CTRL connector on the power amplifier.
DB9 connector (see Amplifier Monitoring section for pinout description).
REMOTE PORT - pin 1: ground to reset microcontroller, float otherwise
pin 2: ground for 2 seconds to toggle carrier on/off, float otherwise
pin 3: common ground
pin 4: DC power supply sample
AC IN – AC input to switching power supply. Switching power supply draws a
maximum of 2 AAC at 110 VAC.
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Technalogix Ltd.
VIII-11
Initial Hook Up
1. Ensure that the antenna has been swept and has a return loss of greater than 20dB (VSWR = 1.2:1).
This should be done before connecting the antenna cable to the transmitter output.
2. Place the transmitter/translator in its permanent location near a receptacle supplying required AC
voltage.
DO NOT APPLY AC POWER AND TURN ON POWER TO THE TRANSMITTER /
TRANSLATOR AT THIS TIME SINCE THE RF OUTPUT MUST BE PROPERLY
LOADED BEFORE OPERATION.
3. Place an appropriate AC power line protector, conditioner, and/or surge suppressor across the AC
supply line.
4. Hook up the modulator or processor as shown in their respective manuals for a transmitter or translator.
Do not connect the modulated signal from the RF OUT on the modulator or processor to RF IN on the
power amplifier at this time. Because of the characteristics of LDMOS devices, the RF drive should not
be connected to the power amplifier until after the power supply and bias voltages are present and
stable.
5. Ensure that modulator or processor RF output level is turned down as far as possible.
6. Ensure that the audio modulation is set to 100% with the audio signal supplied, as described in the
appropriate modulator/processor manual (will be factory set).
7. Ensure that the video modulation level is set to 87.5% with the video signal supplied, as described in
the appropriate modulator/processor manual (will be factory set).
8. Install the DB9 cables from each power amplifier enclosure to the combiner/filter enclosure. It does
not matter which DB9 cable is used as they are both identical.
9. Install the RF cables between the power amplifiers and the combiner/filter enclosure. The cable labelled
PA1 goes between PA1 and the PA1 input on the combiner/filter enclosure and the cable labelled PA2
goes between PA2 and the PA2 input on the combiner/filter enclosure. These cables are phase
matched and must be hooked up on their respective power amplifiers.
10. There is no PSU external to PA’s.
11. Connect the transmitting antenna cable to the RF OUT N-type connector on the filter enclosure RF
output.
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IX-
1
Section IX - Operating Procedure
Assuming the previous installation instructions have been completed and cautions noted, and the TAV-1000
power amplifier is ready to receive a properly modulated video and audio signal, proceed with the following steps
to place the system in operation. The TAV-1000 power amplifier has been factory aligned for channel frequency
(per system specification), signal levels and optimum performance.
1. Do not apply RF drive signal to the power amplifier at this time.
2. Verify that all control and RF cables are tight and properly seated in or on the mating connector.
3. Plug the modulator or processor into AC mains (110Vac).
4. Plug the 5U combiner/filter enclosure into AC mains (110Vac).
5. On the combiner/filter enclosure switch AC rocker switch to “ON” position.
6. Verify that the combiner enclosure’s fan is on.
7. Plug the 5U power amplifier enclosures into 220V AC mains.
8. On the power amplifier, simultaneously switch the AC rocker switches to “on” position.
9. Verify that the power amplifier fans are all on.
10. Ensure that the modulator/processor is turned on and set up according to its instructions. Depress the
POWER tactile button to turn the unit on.
11. The internal soft start circuitry will turn the bias voltages off until the power supply to the amplifier pallets is
fully stable. The message on the LCD indicates when the soft start is running. Once complete, the Forward
and Reflected Power and Power Supply readings will appear on the LCD in the filter and power amplifier
enclosures.
12. After the soft start is complete, apply the RF drive signal (which still should be turned down) between the
modulator or processor and the power amplifier RF In. This ensures that the RF drive signal is applied only
after the power supply is stable and the bias voltages are applied to the amplifier.
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IX-
2
13. The TAV-1000 LCDs show the user the present status of the amplifiers. Adjust RF output power to desired
level (see Important RF Power Notice in previous section). Verify that the FWD Power reads 800 to 1,000
Watts on the combiner/filter enclosure - depending on signal content. The system is set up for 1,000 watts
peak visual power using the sync and blanking signal and should read 1,000 watts FWD Power on the LCD
under this condition only. The output power level can be adjusted using the modulator or processor’s RF
output level adjust. Keep in mind that the system will shut down should the forward RF output power level be
exceeded.
14. Ideally, the RFL Power should read zero. However, should a high VSWR be detected, the system will
automatically shut down and cycle as previously described. This is also a peak wattage reading.
15. Verify that the power supply reads approximately 30 Volts DC (see supplied final inspection sheet for
factory settings of power supply levels) on the LCD of the power amplifier and power supply enclosures and
24Vdc on the combiner/filter enclosure.
16. Look at the transmitted output using a suitable monitor. The picture and sound quality should be clean and
sharp. If the output picture and sound quality is unsatisfactory, check the input signals, connections to the
antenna system, antenna and transmission line VSWR, and the physical condition of the antenna.
If reception problems are encountered, and the quality of transmission is satisfactory, the difficulty is often with
the receiving antenna or with obstructions in the path between the transmitter/translator and receiver.
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X-1
Section X – Maintenance and Troubleshooting
Periodic Maintenance
If your unit employs a filter on the air inlet for the fans, the filter should be cleaned every 30 days. If the
equipment is operated in a severe dust environment, the filters on the inlet fan may need to be cleaned more
regularly. Turn the system off and unplug all of the AC inlet cords. The filter can be lifted off the fan and
cleaned using an air compressor at low pressure. While the filter is out, clean the fan blades themselves with a
small brush. The fans themselves do not need lubrication.
The interior of the cabinets should be cleaned and inspected annually. Turn the system off and unplug all of
the AC inlet cords. Remove the top lid by unscrewing the 6-32 machine screws.
Use extreme caution when working near the AC input terminal. The power amplifier and
power supply store hazardous capacitances and voltages.
Using either compressed air or a brush with soft bristles, loosen accumulated dust and dirt and then vacuum the
interior of the cabinet. Complete a visual inspection of the interior, making sure there are no loose connections
or discolorations on any components from heat. Nothing inside the power amplifier enclosure exceeds a
temperature that is not comfortable to the touch under normal operating conditions, so any signs of discoloration
indicate potential damage.
All modular components inside the enclosure are attached to aluminium mounting plates for easy removal and
replacement. Ensure that plates are secured and the mounting hardware is tight.
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X-2
Troubleshooting
The first and most important aspect of troubleshooting anything is to be systematic. Note where you have
looked and what you found.
Look first for the obvious.
• Make a physical inspection of the entire facility. Are all necessary connections properly made? Do you
see any signs of obvious damage within the equipment?
• Is the AC power ‘ON’ to the site and the equipment? (Check fuses and circuit breakers if necessary.)
• Are all the switches in the correct operating position?
• Is the input signal present?
• Check LCD readings for presence of forward and reflected power and 31 V DC supply levels.
The above is an aid in determining the fault if some aspect of the system is not operating. The following table
deals with quality of operation:
Symptom Possible Fault Correction
Horizontal bars in picture (may roll
either way depending on phase) AC grounding / AC interference Install EMI/RFI filter in AC line
Ensure modulator/processor and
power amplifier share a common
ground
Diagonal lines in picture Interference Install EMI/RFI filter in AC line
Determine source and frequency
of interfering signal (spectrum
analyzer may be required)
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X-3
Symptom Possible Fault Correction
Weak output or picture Low level input signal Verify presence and level of input
signal
Low output power Verify power amplifier output with
wattmeter and dummy load
Incorrect modulation depth Adjust to meet specification
High reflected power Incorrect load Ensure amplifier connected to
transmission line
Ensure correct antenna impedance
(50 ohms)
Check antenna tuning and
VSWR. Verify correct cable for
transmission line length
Check all cables for visible
damage (kinks, nicks or cuts)
Check all connectors for poor
connections, water or corrosion
Check alignment of antenna
Check for physical damage of
antenna, including ice build-up