TB8100 Service Manual 9
© Tait Electronics Limited September 2006
List of Illustrations
Safety and Servicing Information
Figure 1.1 Typical antistatic bench set-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 1.2 Identifying Torx screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 1.3 Identifying Pozidriv and Phillips screws and screwdrivers . . . . . . . . . . . . . . . . . 24
Reciter Circuit Description
Figure 2.1 Reciter high level block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Figure 2.2 Reciter digital circuitry block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Figure 2.3 Reciter RISC functional block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Figure 2.4 Reciter external reference block diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Figure 2.5 Reciter VHF receiver RF circuitry block diagram . . . . . . . . . . . . . . . . . . . . . . 38
Figure 2.6 Reciter receiver synthesizer block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Figure 2.7 Reciter UHF receiver RF circuitry block diagram. . . . . . . . . . . . . . . . . . . . . . 42
Figure 2.8 Reciter receiver synthesizer block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Figure 2.9 Comparison of VCXO and VCO modulation responses . . . . . . . . . . . . . . . . . 48
Figure 2.10 Reciter exciter synthesizer modulator block diagram - B, C and H bands . . . . . 49
Figure 2.11 Reciter exciter synthesizer modulator block diagram - K and L bands. . . . . . . . 50
Figure 2.12 Reciter system interface board block diagram . . . . . . . . . . . . . . . . . . . . . . . . . 56
Figure 2.13 Reciter power supply block diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Figure 2.14 Identifying the circuitry on the digital and system interface boards . . . . . . . . . . 61
Figure 2.15 Identifying the circuitry on the RF board - B and C bands . . . . . . . . . . . . . . . 63
Figure 2.16 Identifying the circuitry on the RF board - H band . . . . . . . . . . . . . . . . . . . . . 65
Figure 2.17 Identifying the circuitry on the RF board - K and L bands. . . . . . . . . . . . . . . . 67
Reciter Fault Finding
Figure 3.1 Identifying the reciter boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Figure 3.2 Recommended test equipment set-up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Figure 3.3 Typical 12.8MHz clock wave form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Figure 3.4 Location of the 12.8MHz clock test point on the RF board. . . . . . . . . . . . . . . 81
Figure 3.5 Visual inspection points for the reciter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Figure 3.6 Recommended test equipment set-up for audio checks . . . . . . . . . . . . . . . . . . 90
Figure 3.7 Location of audio test points on the digital board. . . . . . . . . . . . . . . . . . . . . . . 91
Figure 3.8 Location of audio test points on the system interface board. . . . . . . . . . . . . . . . 94
Reciter Disassembly and Reassembly
Figure 4.1 Removing the front and rear panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Reciter Board Replacement
Figure 5.1 Replacing the system interface board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Figure 5.2 Reconnecting the flexible connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Reciter Spare Parts
Figure 6.1 Reciter mechanical assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111