T858/859 Fault Finding
D4.11
Copyright TEL
4.6.4
T859 Power Control
Approximate voltages under normal operating conditions:
Measurement
Output Power
20W
50W
forward power at "FWD-PWR" pad (beside IC3)
RV63/R64 (RV63 wiper)
2.5V
1.4V
4V
2.1V
Does power control work?
Check 12V DC present
on IC1 pin 14.
Check sense voltages
from directional coupler.
Check IC3 pins 7 & 1.
Check Q10 & Q11.
Check IC1 pin 1 >12V DC
when forward power low.
Does forward power
alarm output work?
Does reverse power
alarm output work?
Check Q12 & Q13.
Check IC1 pin 7 >12V DC
when reverse power high.
Heat R72 with tip
of soldering iron.
Heat R72 with tip
of soldering iron.
Check IC1 pin 13 is at 0.6V.
Check IC1 pin 14 goes from
high to low as R72 heats up.
Check D17.
Power control OK.
N
N
N
N
Y
Y
Y
Y
CAUTION
The following voltage checks
are all done with RV69
(driver power level)
set to maximum.
Does temperature
shutdown circuit
turn down output power?
Summary of Contents for T850 II Series
Page 12: ...12 M850 00 31 09 98 Copyright TEL...
Page 14: ...AII M850 00 31 09 98 Copyright TEL...
Page 20: ...A2 4 Mechanical M850 00 31 09 98 Copyright TEL...
Page 26: ...BII M850 00 31 09 98 Copyright TEL...
Page 28: ...B1 2 T855 General Information M850 00 31 09 98 Copyright TEL...
Page 40: ...B1 14 T855 General Information M850 00 31 09 98 Copyright TEL...
Page 42: ...B2 2 T855 Circuit Operation M850 00 31 09 98 Copyright TEL...
Page 68: ...B4 2 T855 Functional Testing M850 00 31 09 98 Copyright TEL...
Page 74: ...B4 8 T855 Functional Testing M850 00 31 09 98 Copyright TEL...
Page 94: ...B5 20 T855 Fault Finding M850 00 31 09 98 Copyright TEL...
Page 96: ...B6 1 2 T855 PCB Information M850 00 31 09 98 Copyright TEL...
Page 102: ...B6 2 2 T800 04 0000 RSSI PCB Information M850 00 31 09 98 Copyright TEL...
Page 108: ...B6 3 2 T855 PCB Information M850 00 31 09 98 Copyright TEL...
Page 115: ...IPN 220 01396 02 M850 00 T855 PCB Information B6 3 9 Copyright TEL 31 09 98...
Page 122: ...IPN 220 01396 02 B6 3 16 T855 PCB Information M850 00 31 09 98 Copyright TEL...
Page 124: ...CII M850 00 31 09 98 Copyright TEL...
Page 126: ...C1 2 T856 857 General Information M850 00 31 09 98 Copyright TEL...
Page 140: ...C1 16 T856 857 General Information M850 00 31 09 98 Copyright TEL...
Page 154: ...C2 14 T856 857 Circuit Operation M850 00 31 09 98 Copyright TEL...
Page 170: ...C4 2 T856 857 Functional Testing M850 00 31 09 98 Copyright TEL...
Page 176: ...C4 8 T856 857 Functional Testing M850 00 31 09 98 Copyright TEL...
Page 198: ...C6 1 2 T856 857 PCB Information M850 00 31 09 98 Copyright TEL...
Page 204: ...C6 2 2 T856 PCB Information M850 00 31 09 98 Copyright TEL...
Page 220: ...C6 3 2 T857 PCB Information M850 00 31 09 98 Copyright TEL...
Page 232: ...IPN 220 01398 02 C6 3 14 T857 PCB Information M850 00 31 09 98 Copyright TEL...
Page 234: ...DII M850 00 31 09 98 Copyright TEL...
Page 236: ...D1 2 T858 859 General Information M850 00 31 09 98 Copyright TEL...
Page 248: ...D2 2 T858 859 Circuit Operation M850 00 31 09 98 Copyright TEL...
Page 256: ...D3 2 T858 859 Initial Adjustment M850 00 31 09 98 Copyright TEL...
Page 264: ...D3 10 T858 859 Initial Adjustment M850 00 31 09 98 Copyright TEL...
Page 266: ...D4 2 T858 859 Fault Finding M850 00 31 09 98 Copyright TEL...
Page 282: ...D5 1 2 T858 859 PCB Information M850 00 31 09 98 Copyright TEL...
Page 288: ...D5 2 2 T858 PCB Information M850 00 31 09 98 Copyright TEL...
Page 293: ...IPN 220 01141 01 M850 00 T858 PCB Information D5 2 7 Copyright TEL 31 09 98...
Page 298: ...IPN 220 01141 01 D5 2 12 T858 PCB Information M850 00 31 09 98 Copyright TEL...
Page 300: ...D5 3 2 T859 PCB Information M850 00 31 09 98 Copyright TEL...
Page 305: ...IPN 220 01159 01 M850 00 T859 PCB Information D5 3 7 Copyright TEL 31 09 98...
Page 312: ...EII M850 00 31 09 98 Copyright TEL...
Page 316: ...E2 2 T850 VCO PCB Information M850 00 31 09 98 Copyright TEL...
Page 328: ...G1 4 T855 Link Selectable Features M850 00 31 09 98 Copyright TEL...
Page 332: ...G2 4 T856 857 Optional Features M850 00 31 09 98 Copyright TEL...
Page 334: ...G3 2 Talk Through Repeater M850 00 31 09 98 Copyright TEL...
Page 340: ...HII M850 00 31 09 98 Copyright TEL...
Page 356: ...I II M850 00 31 09 98 Copyright TEL...
Page 358: ...I1 2 Tools Required M850 00 31 09 98 Copyright TEL...
Page 366: ...I2 8 T855 856 857 SII SI Conversion M850 00 31 09 98 Copyright TEL...
Page 370: ...I3 4 T858 859 SII SI Conversion M850 00 31 09 98 Copyright TEL...