Burghardt Amateur Center BU-1000 BU-1000 Data Transceiver Board User Manual 87376
Burghardt Amateur Center BU-1000 Data Transceiver Board 87376
iNSTALLATION INSTRUCTIONS
BU-1000 INSTALLATION
The BU-1000 has a 5 pin connector for hookup to the MRU(meter reading unit)
modem and a BNC connector for connection to a half wave dipole. The Pin-out of
the 5 pin connector is as follows.
1)PTT(push to talk)
2)12V(regulated 12 volt input)
3)mod in(modulation input)
4)RXA(receiver audio output)
5)GND(ground)
THEORY OF OPERATION
The BU-1000 is a low power data transceiver.
RECEIVER SECTION
The receiver is a double conversion superhetrodyne design. When in the receive
mode, signal is allowed to pass to Q1 RF AMP where it is amplified and sent to
U1 for the first mix. X2 is a 3rd overtone crystal which is tripled by Q2 to produce
the first mix frequency. The first mixer is located in U1 and produces a 10.7MHZ
first IF. X1 produces the 2nd mix frequency of 10.245MHZ. It is mixed in U1 to
produce a 455KHZ 2nd IF frequency. Receiver audio is then detected in U1 to
produce RXA out.
TRANSMIT SECTION
Modulation is applied to D3 varactor and is used to shift the frequency of X201 to
produce FM modulation. X201 is a 3rd overtone crystal. Its frequency is tripled by
Q241 to give the apropriate output frequency. It is then amplified by Q242
predriver and Q243 final. It is passed through D440/441 switching when in
transmit mode and from there applied to the antenna.
BU-1000 SPECIFICATIONS
GENERAL
FREQUENCY COVERAGE:1 CHANNEL
(173.20375/173.21/173.2375/173.2625/173.2875/173.3125/173.3375/173.3625/
173.39/ OR 173.39625 MHZ)
TX CURRENT DRAW: 250MA
RX CURRENT DRAW: 120MA
RECEIVER
SENSITIVITY: 10DB SINAD AT .8UV
AUDIO OUTPUT LEVEL: 2VPP AT 3KHZ DEVIATION
1ST IF FREQUENCY: 10.7 MHZ
2ND IF FREQUENCY: 455 KHZ
TRANSMITTER
POWER: 250MW
BU-1000 DATA TRANSCEIVER BOARD PARTS LIST
VERSION 2
RECEIVER SECTION
C2,8,10,11,13,16,17,18,19,20,23,24 .1UF NEWARK 07WX6808
C6 33PF DIGIKEY PCC330CCT-ND
C7 18PF DIGIKEY PCC180CCT-ND
C14 120PF DIGIKEY PCC121CCT-ND
C4 4.7PF DIGIKEY PCC4R7CCT-ND
C15 47PF DIGIKEY PCC470CCT-ND
C5 22PF DIGIKEY PCC220CCT-ND
C12 1UF TANTILUM NEWARK 93F2694
C3 100PF DIGIKEY PCC101CCT-ND
C25 1000PF DIGIKEY PCC102BCT-ND
C21 2200PF DIGIKEY PCC222BCT-ND
R6,2 470 NEWARK 07WX0214
R10,12 39K NEWARK 08WX8266
R3,7,8 1K NEWARK 07WX0211
R4 5.6K NEWARK 08WX8274
R5 15K NEWARK 08WX7826
R1 100K NEWARK 96F6995R100.0K
R9 10K NEWARK 08WX8237
R11,13 22K NEWARK 08WX8252
R14 330 OHM 1/2 WATT DIGIKEY 330H-ND
FL1 E10.7V NEWARK 87F2439
FL2 455KHZ NEWARK 90F2264
L1 43NH DIGIKEY DN4010-ND
L2 1.5UH DIGIKEY TK1412-ND
L3 .108UH DIGIKEY TK2713-ND
L4 .64MH DIGIKEY TK1302-ND
U1 MC13135DW NEWARK 07F2896
U2 78L05ACP NEWARK 07F7397
X1 10.245 MHZ BOMAR
X2 SELECTED BOMAR
Q1 MRF901 NEWARK 08F1298
Q2 2N3904 NEWARK 09F5663
ZD1 6.8 V 1/2 WATT ZENER NEWARK 09F4090
TRANSMITTER SECTION
C265,252,259,260,261,263,272 .1UF NEWARK 07WX6808
C253,254 47PF DIGIKEY PCC470CCT-ND
C255 18PF DIGIKEY PCC180CCT-ND
C262,250 220PF DIGIKEY PCC221BCT-ND
C267 2.2PF DIGIKEY PCC2R2CCT-ND
C271,273 1000PF DIGIKEY PCC102BCT-ND
C268 .01UF DIGIKEY PCC103BCT-ND
R210 470 OHM NEWARK 07WX0214
R212 15K NEWARK 08WX7826
R221,216,211,217 1K NEWARK 07WX0211
R214 5.6K NEWARK 08WX8274
R215,220 18K DIGIKEY P18KECT-ND
R219,223 100K NEWARK 96F6995R100.0K
R222,218 10 OHM DIGIKEY P10ECT-ND
R224 4.7K DIGIKEY P4.7KECT-ND
R225 330 OHM 1/2 WATT DIGIKEY 330H-ND
R226 150 OHM DIGIKEY P150ECT-ND
L290 1.5UH DIGIKEY TK1412-ND
L291 .137UH DIGIKEY TK2714-ND
L292,296,297,299 43 NH DIGIKEY DN4010-ND
L294,300 1UH DIGIKEY PCD1131CT-ND
L295 .241UH DIGIKEY TK2707-ND
L293 .375UH DIGIKEY TK2729-ND
L298 .211UH DIGIKEY TK2706-ND
Q242,241 MRF901 NEWARK 08F1298
Q243 2N4427 NEWARK 10WX2083
X201 SELECTED
ZD2 6.8V ZENER NEWARK 09F4090
D3 MV2105 VARACTOR NEWARK 08F2197
COMMON SECTION
R401,402,403,400 1K NEWARK 07WX0211
C460,461 .1UF NEWARK 07WX6808
L475 56UH DIGIKEY PCD1106CT-ND
D440,441 MPN3404 NEWARK 07F9506
Q450 2N3906 DIGIKEY 2N3906DICT-ND
LED1 GREEN LED DIGIKEY 67-1059-ND
LED2 RED LED DIGIKEY 67-1065-ND
CN1 5 PIN JACK DIGIKEY H2097-ND
CN2 BNC JACK DIGIKEY ARF1178-ND
2 PIN JACK(OPTIONAL) DIGIKEY H2094-ND
5 PIN PLUG(ACCESSORY) DIGIKEY H2086-ND
2 PIN PLUG(OPTIONAL) DIGIKEY H2083-ND
PINS(ACCESSORY) DIGIKEY H2138-ND
VERSION 2(173 MHZ)
C1 56PF DIGIKEY PCC560CT-ND
C258,221 3.9PF DIGIKEY PCC3R9CCT-ND
C9,222 2.2PF DIGIKEY PCC2R2CCT-ND
C224 3.3PF DIGIKEY PCC3R3CCT-ND
C257,251 33PF DIGIKEY PCC330CCT-ND
C256 8.2PF DIGIKEY PCC8R2CCT-ND
C269 6.8PF DIGIKEY PCC6R8CCT-ND
C264 18PF DIGIKEY PCC180CCT-ND