![Tait T800 SL2 25W Скачать руководство пользователя страница 43](http://html1.mh-extra.com/html/tait/t800-sl2-25w/t800-sl2-25w_service-manual_3300420043.webp)
T855 Circuit Operation
B2.11
© Copyright Tait Electronics Limited August 2004. All rights reserved.
2.11
VCO
(Refer to the VCO circuit diagram in Part E.)
The VCO transistor (Q1) operates in a common emitter, and uses a transmission line res-
onator (TL1). The transmission line is used in a two port configuration with varicaps
positioned at one end. The VCO control voltage from the loop filter (IC750) is applied to
the varicaps (D1 and D2) to facilitate tuning. The VCO output is coupled into a cascode
amplifier stage (Q2 and Q3) which su10dBm (nominal) output. Further amplifi-
cation in Q5 brings the output drive level to +20dBm to drive the mixer.
A low level “sniff” is taken from the input to Q5 to drive the divider buffer to the syn-
thesiser (IC740).
The VCO operates at the actual frequency required by the first mixer, i.e. there are no
multiplier stages.
The VCO frequency spans from 355 to 395MHz, 395 to 435MHz or 435 to 485MHz
according to product type. The VCO is tuned to 45MHz below the desired receive fre-
quency (low side injection) to produce a 45MHz IF signal at the output of the mixer.
Содержание T800 SL2 25W
Страница 8: ...8 M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 10: ...AII M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 16: ...A2 4 Mechanical M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 20: ...BII M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 34: ...B2 2 T855 Circuit Operation M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 86: ...B5 20 T855 Fault Finding M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 88: ...B6 1 2 T855 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 92: ...B6 1 6 T855 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 102: ...B6 3 2 T855 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 108: ...B6 3 8 T855 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 130: ...CII M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 132: ...C1 2 T854 General Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 154: ...C2 14 T854 Circuit Operation M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 178: ...C4 2 T854 Functional Testing M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 186: ...C4 10 T854 Functional Testing M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 206: ...C6 1 2 T854 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 210: ...C6 1 6 T854 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 212: ...C6 2 2 T854 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 242: ...DII M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 260: ...D2 2 Circuit Operation M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 268: ...D2 10 Circuit Operation M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 288: ...D4 1 2 T803 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 292: ...D4 2 2 T803 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 308: ...EII M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 312: ...E2 2 T850 VCO PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 316: ...E2 6 T850 VCO PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 320: ...FII M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 326: ...F1 6 General Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 334: ...F5 2 Troubleshooting M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 338: ...F6 4 Service Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 346: ...G1 6 M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 350: ...G1 10 T800 SL2 M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 358: ...G3 2 Talk Through Repeater M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 365: ...G6 1 2 X800 56 PCB3 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 368: ...G6 2 2 X800 56 PCB3 PCB Information M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...
Страница 378: ...HII M8SL2 00 002 812 Copyright Tait Electronics Limited August 2004 All rights reserved...