TM8100/TM8200 Service Manual
Fault Finding of Control Head with Graphical Display
421
© Tait Electronics Limited
June 2006
Several Keys Faulty
The keys can be grouped into columns and rows of three or two keys, as
illustrated in
.
If one column of keys is faulty:
1.
Visually inspect the associated resistor and diodes for open or shorted
circuits.
If one row of keys is faulty:
1.
Visually inspect the associated resistor for open or shorted circuits.
F2 key
F4 key
scroll-up key
R620
D602
F1 key
right selection key
scroll-down key
R621
D620
F3 key
left selection key
R622
D604
F3 key
F4 key
right selection key
R623 scroll-up key
scroll-down key
left selection key
R624 F1 key
F2 key
R625
Figure 14.12 PCB layout of the function, scroll, and selection key circuitry
top side
bottom side
Summary of Contents for TM8235
Page 1: ...TM8100 mobiles TM8200 mobiles Service Manual MMA 00005 04 Issue 4 June 2006...
Page 10: ...10 TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 62: ...62 Description TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 148: ...148 Disassembly and Reassembly TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 162: ...162 Servicing Procedures TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 178: ...178 Interface Fault Finding TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 258: ...258 Receiver Fault Finding TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 446: ...446 Spare Parts TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...