8
| Download: |  |
| Mirror Download [FCC.gov] | |
| Document ID | 79314 |
| Application ID | q1m2AcP4JVLdiFL9Dgx4oA== |
| Document Description | 8 |
| Short Term Confidential | No |
| Permanent Confidential | No |
| Supercede | No |
| Document Type | User Manual |
| Display Format | Adobe Acrobat PDF - pdf |
| Filesize | 18.82kB (235235 bits) |
| Date Submitted | 2000-01-04 00:00:00 |
| Date Available | 1998-09-26 00:00:00 |
| Creation Date | 2001-05-03 11:47:27 |
| Producing Software | Acrobat Distiller 4.0 for Windows |
| Document Lastmod | 2001-05-03 11:47:29 |
| Document Title | 8 |
21/07 "95 "RE lJ’ZQ FAY 764_ 3 3594632 RSVD ~_DE\'El,0‘lj‘_ll\’T ‘006
MBEUvOO TESS/837 Initial Tuning 5 Adjustment 03.5
ID: CASTELOOOS
3.4 Short Tuning Procedure 2.933 (M9, ALIGNMENT: TUNE)?
Use this procedure only if you want to reprogram the T836/837 to a frequency outside
the BMHz switching range and do not intend to carry out any other major adjustments
or repairs.
3.4.1 Introduction
Reprogram the operating frequency as described in the PGMSOOWrn program—
ming kit (refer to Section 3.2).
Remove the top cover (nearest the handle).
Set up the test equipment as desaibed in Section 3.3.
Set the links in the audio processor section as required (refer to Section 3.5).
3.4.2 Synthesiser Alignment
' Connect a high impedance voltmeter to PIA-1 or the junction of L1 Gr R1 in the
VCO (this measures the synthesiser loop voltage).
- Key the transmitter by earthing the Tx—Key line.
- Single Channel Tune VCO trimmer C‘Vl for a synthesiser loop voltage of
9\/.
Multichannel Tune VCO trimmer CV I for a synthesiser loop voltage of
. 9V on the middle channeL
If there is no middle channel, tune CV1 so that the chan—
nels are symmetrically placed around a loop voltage of 9‘/.
All channels should lie within the upper and lower limits
of 13V and SV respectively.
Do not attempt to program channels with a greater fre-
quency separation than the specified swrtching range of
EMHZ.
3.4.3 Output Power Adjustment (T 836 Only)
Connect an RF power meter to the output socket and key the transmitter.
Turn RVJZO (power adjust) fully clockwise.
Tune CV451 (output power trim) for maximum out-put power and check that this
is >30W.
Adjust RV320 for the required output power (between 5 and 25W).
Readjust CV451 to reduce the supply current by up to 0.5A.
Copyright TEL 30/04/98
21/07
'95 “ME 14:24 FAX 64 3 3594632 RSD ~ DEYELDPHNT
03.6 Tess/537 Initial Tuning & Adjustment Mason]
3.4.4 Two Point Modulation Adjustment
Male 1.‘
In this and following SECfiOns deviation settings are given first for wide
bandwidth sets, followed by settings in brackets for mid bandwidth sets ( )
and narrow bandwidth sets I l.
Noll2: Reference modulation and limiter adjustment are controlled by
PGMBGOWin Electronic potentiometers (256 step) are used to allow chanA
nel—by—channel adjustment of deviation and two point modulation.
Note 3: To optimise the modulation response across the switching range, repeat
Note:
3.4.5
Note:
steps 1-4 below for each channel that will be used (usually needed only for
data applications). In applications where the modulation response is less
critical (e.g. voice use only), catty out steps 14 below on the middle channel
and cut and paste the value to all other channels.
Inject an audio Slgflal of 600m LEV rms (+5dBrn) into the Cl'CSS input (D~range
l (PLIOO) pin 8).
Key the transmitter by earthing the Tx-Key line.
Adjust the output from the audio generator to obtain 13kl-lz (tZAkHz) [tLSkl—lzl
deviation at 600Hz.
Change the input frequency to 1201-12 and adjust ”reference modulation" via
PGMBOOWin to obtain :3k.Hz (zlélkHz) [tLSkHz] deviation (you can use either
the mouse or up and down arrow keys).
Change the input frequency back to 600Hz.
Repeat steps 2 and 3 above until the deviations achieved at the two input frequen-
cies are within 0.2dB of each other. You will need to do this at least four times.
Sweep the audio between 50 and 300Hz for peaks.
A peak between 50 and 300111 will indicate a fault condition, i.e:
- incorrect set—up
or - modulation cirtuitry fault.
The specification window is zldB relative to 1501-12 from 65 to 260m.
FM Deviation (Limiter) Adjustment
If the TESS/837 will be used over the whole BMHz switching range, you
must set the deviation for each channel. However, if the module will be
used on frequencies that cover only a lMHz (or less) switching range, you
can set the deviation on the middle channel and use this value [or all other
channels with the "till" option in PGMEOOWin.
Inject lkl-[z at ~lDdBm into the line input (Dvrange l (PLlOO) pins 1 Sr 4; pins 2 Gt 3
shorted; refer to Section 2.2 of Part F).
30/04/98 Copynghl TEL
Imam
21/07 '95\ TL'E 14:25 FAX 64 3 3594632 RSI) . DEVELUPHNT Elflflfl
Meaooo T836/037 Inn/a! Tuning 4 Adjustment 63,7
Adjust RVZIO (line sensitivity) fully clockwise and key the transmitter by sax-thing
the Tx-Key line. Adjust ”deflation" via PGMBOOWin to set the peak deviation to
$4.7kHz (23.3kHz) [zZSkHz] (you can use either the mouse or up and down
arrow keys).
Sweep the audio frequency from IOOHz to 4kHz and ensure that the maximum
deflation does not exceed 4,71d-{z (13.8kHz) [2.3kHz]. Readjust "deviation“ if
necessary via PCMSOOWin.
3.4,6 Line-in Level Adjustment
Set the injected signal at the Line input to the required line level (typically —10 to
40am).
Adjust RV 210 (line sensitivity) to provide szHz (flAkHz) [21510111] deviation.
Copyn'gm TEL 30mm
"W?
21/07 '% TUE 14:22 F.-\.\ GA 3 3591632 R51] — DEVELOPVlM‘ ‘anq
if
62.12 TB3fi/837 circuit Operation mesa-Do
. .- ID: CASTELOOOS
2.8 T836 Drive Amplifier&PA 2.933 mm) CIRCUIT DESC,
(Refer to Figure 2.1 and the exciter and PA circuit diagrams (sheets 3 Sr 4) in Section 62.)
The output power of the PA is maintained at a constant level via a power control loop
applied to the two—stage, wide band exciter amplifier (Q365, Q370). The forward and
reverse RF power levels are sensed via a dual directional coupler and detector diodes
(D410, D420 in the PA cavity), The detected DC signals are summed with the ’power
adjust' level and fed to the control integrator (1C330 pins 1, 2 K: 3). The output control
voltage is buffered by Q310 and 0315, and applied to the collectors of the Wide band
exciter amplifier.
Nola: Forward and reflected power signals are summed so that, under high
VSW'R, the power control will turn the output RF level down.
To reduce the spurious output level when the synthesiser is out-of-Iock, the Tat-Reg. and
Lock-Detect signals are gated to inhibit the PA control circuit and to switch off the RF
signal at the input to the drive amplifier. This is achieved by a Pm switch attenuator
(D340, D350, D360).
Cyclic keying control is provided by additional circuitry consisting of several time
delay, ramp and gate stages:
- Q350, Q355, (2360, [C330 pins 1, 2 6x 3 powa ramping
~ our), Q345 Tit-Reg. and m gate
0 (2320, Q325, (2330, Q335 delay and PIN switch drive.
This is to allow the RF power circuits (both exciber and PA) to ramp up and down in a
controlled manner so that minimal adjacent channel interference is generated during
the transition.
The output of the wide band amplifier is approximately SDOrnW (+27dBm) for an input
of 170mW (+22dBm) when the power control is set to maximum
The later diode (D330) limits the upper range of the controlled voltage to the exciter
transistors.
A temperature sensor (R460) is provided so that the RF output power can lie reduced to
a preset level when a set temperature is exceeded. This is a protection circuit (IC330
pins 5, 6 & 7, Q305) to prevent overheating, as the unit is not rated for continuous oper~
atiort at high temperatures (refer to Section 1.2.3 for duty cycle spedficalions]. RV330
sets the PA output power while under high temperature fold-back conditions.
R359, R360 and R362 form a 6dB attenuator to provide good VCO/exciter isolation.
The output attenuator (R392, R390, R394 and R396) aids in reducing exdter/PA interac-
tion while also ensuring a reasonable match for 0350.
The RF output from the exoter is fed to the driver stage (Q415) and then to the final
(Q425). DC is fed to the final via a low pass filter with special low frequency decou-
pling. CV451 tunes the output matching across the entire band.
30/0de Copyright TEL
ID: CASTELOOOS
2.983 (dHS) MANUAL
T830 Series II
Base Station Equipment
Service Manual
Preliminary Issue
August 1997
(Not For Resale)
Cupynghi TEL
August 1997
About This Manual
Scope This manual contains preliminary servicing information on T830
Series II 25W, 50W and 100W base stations which comprise the
following equipment:
25W base station T835 receiver
T836 25W transmitter
50W base station T835 receiver
T837 exciter
T3338 50W power amplifier ,
100W base station T835 receiver
T837 exciter
T839 100W power amplifier A
Contents Part A contains information on the following procedures:
' changing the operating frequency
- retuning the module after changing frequency
- configuring the audio processor
- T838/839 user informanon
Parts B to G contain the following PCB information:
- parts liss
' grid reference indexes
' PCB layout diagrams
- test points & options diagrams
- circuit diagrams
Part H contains the following information on the TSOQZZOOUU
rack frame:
- general information
~ circuit operation
0 parts lists
' PCB layout diagrams
Technical Information
Any enquiries regarding this manual or the equipment it describes should be addressed
in the first instance to your nearest approved Tait Dealer or Service Centre Further
technical assistance and copies of this manual may be obtained from the Customer Sup-
port Group, Radio Infrastructure Division, Tait Electronics Ltd, Christchurch, New Zea-
land.
Date Of Issue
T830 Series II Preliminary SerVice Manual published August 1997
Copyright TEL August 1997
{9
Changing the Operating Frequency of the T800 SeriesII
Ovethew
Introduction When you receive the T800 module it will be run up and working on a par-
ticular frequency. Sometimes you may want to change the operating fre—
quency. In some cases. when you change the operating frequency, it will
also be necessary to re»tune the radio to ensure correct operation.
Purpose of this It is the purpose of this document to familiarise you with the procedures
document that must be carried out to check that the radio is still operating correctly,
and how to reflune the radio when this is not the case.
__—____—_______——-—-—
In this section This section covers the following topics:
Topic See page
How to change the operating frequency 2
How to re-tune the T835 4
How to re-tune the T836/837 7
Configuring the Audio Processor 11
How to determine ifthe T835/836/837 15 still operating 16
Page 1
t tpmyectswn up- namummmmgmq 11 mm
II'III
Changing the Operating Frequency of the T800 Series II
How to change the operating frequency
Description
After changing the
operating frequency
What is the
switching band
There are two possible ways of changing the operating frequency:
Method 1 By using a computer running PGMiimiwtn and
- Changing the default channel in the existing setup
or
- Reprogramming the radio channel frequencies and then select-
ing a default channel
NOTE. Please refer to the T830 service manual and the PGMKODWIN
programming manual for further mstniclion
Method 2 By selecting a new channel using the DIP switch on the rear of the
PCB Backplane or some other form of installed channel change
switch i,e. BCD. Internal DIP switch.
____.___———-——_——
Having changed the operating frequency of the T830 there are two differ-
ent scenarios you will be faced with:
- You will change the frequency and the T830 will continue to operate
correctly in this case you have changed to a frequency within the
switching band of the radio.
- You will change the frequency and the T830 will not operate or will not
operate correctly In this case you have changed to a frequency outside
of the switching band.
Note: The radio must now be re-tuned (see next section “How to re»
tune the T835” & “How to re-tune the Two/837").
_—_____—_—-——_
Because of the high RF performance of the T8100 series there is a limit to
the amount of frequenCies that the radio can switch to before re~tuning
must occur. The limit is referred to as the switching bandwidthi
' The T830 Rx can swnch up to 3MHZ.
0 The TS30 Tx can switch up to SMHZ.
So ifthe T830 is optimally tuned to a centre frequency (which is often the
case when sent from the factory) then the Rx or Tx will be able to switch
half the switching band either side of that frequency
___________-_———————
c Mojectflmn~up~lmncunwntwhnglvtq
x i/tnm Page 2
Changing the Operating Frequency of the T800 Series"
How to re-tune the T836/837
Equipment required You will need:
Computer with PGMSOOWin installed
TSOO programming kit
TSOO test & calibration unit
Digital multimeter
Oscilloscope (digital preferred)
Audio Signal generator
Audio voltmeter x 2
RF power meter
Modulation meter
20dB pad
or
Computer with PGMSOOWin installed
T800 programming kit
TSOO test & calibration unit
RF test set
Before you start ° Remove the top cover of the module (the side closest to the handle).
- Set up the test equipment as shown below.
Audio
zoda our gutter
was and: tmnsmmsr
,,,,, qumney
1 County
Mewlatmn
&\ Meter
—~Ge”'flm crcss up
cannecnan to computer
via PGMstln
- Set the jumpers in the audio section of the modu
[ion “Configurring the Audio Processor").
raw van a?
cfllbtcflon ;
test set _
RF Power
Vultmutar
AF on:
mat-1mm
e as required (see sec—
' Connect the computer to the module usmg the PGMSOOWin programv
ming kit.
—____._—.—-———-—————_—
c mummy, up—Ildotumtntwlmgtrcq
wmm
Page 7
Ifilll
Changing the Operating Frequency of the T800 Series II
How to re-tune the T836/837 cont"
Steps involved
Procedure
The service manual has a section which describes a full Initial Tuning and
Adjustment procedure. This must be used if a repair has been made or
some other major characteristic has been changed. If the only adjustment
made has been to switch to a channel outside the switching band, then the
followmg steps should be followed.
~ Change the operating frequency
- Lock the VCO to produce the output frequency
- Adjust the output power
' Set the dual point modulation
' Set the FM deviation
- Reset the line»in level
The procedure is described below.
Follow the steps below to retune the T8315 or T837 if the frequency has
been changed and the radio stops operating.
Step Action
LLock the VCO to produce the output frequency
1 Connect a high impedance voltmeter to the long lead ole in the
VCO (ll’llS measures the synthesiser loop voltage.
2 Single channel
Tune VCO trimmer C6 for a synthesisur loop voltage of 10V.
Multichannel
Tune vco trimmer C6 for a synthesiser loop voltage of 10V on
the middle channel.
If there IS no middle channel, tune C6 St) that the channels are
symmetrically placed around a loop voltage of IOV,
All channels should lie wllhlrl the upper and lower limlts ol' 16V
and 3V respectively.
Do not attempt lo programme channels with a greater frequency
l—scparatlon Ihan the spectfied swllchmg range
r \pvojt'u>lnm upelldueumrnthhngln‘q
lmnm Page 8
Changing the Operating Frequency of the T800 Series"
Configuring the Audio Processor cont..
T836/I‘ 837 audio
processor links cont..
c \prmcm\nmrup~ imcummmhngmq
”Rim
\§
wax
54
5155
in, PM
sn-
mm
mun-mm
<5
(Mame m. Mod.
vco
T836/837 Audio processor block
diagram showing link options
“mm
Changing the Operating Frequency of the T800 Series II
How to determine if the T835/836/837 is still operating
Introduction If the radio was working fine and you want to check that it is still operat—
ing correctly, afler changing the operating frequency, follow the steps
listed below.
Procedure Follow the steps below to perform a quick check of correct operation.
Step Action J
1 Remove the top cover of the module (the side closest to the ham
dle).
2 Connect a high impedance voltmeter to the long lead ot'Lln the
VCO (this measures the synthesiser loop voltage.
3 Ensure the measured DC vullage is between 5 & 15V
Note: If the T835 Receiver is not operating this will be indicated by a
slow flashing of the Green Supply light. This should be used as a visual
check followed by the more definitive check given above,
_———_—_—__
t wt‘lrtlflmn-up—lmucumenflthnglmq rim/v7 Page 16
Source Exif Data:
File Type : PDF File Type Extension : pdf MIME Type : application/pdf PDF Version : 1.2 Linearized : Yes Create Date : 2001:05:03 11:47:27 Producer : Acrobat Distiller 4.0 for Windows Modify Date : 2001:05:03 11:47:29-04:00 Page Count : 12EXIF Metadata provided by EXIF.tools