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IC-746 FAQ
Service Manual Discrepancies
The "Service Manual" is supposed to be the best, final word on the electronics within the IC-
746. However, the data it contains isn't always consistent. Here are the known
discrepancies.
Identity of Q302
Q302 on the S-Logic Board is a driver transistor for the LCD backlight. It's listing varies
depending upon the reference within the Service Manual. We'd love to hear which part is
actually in your rig.
p.
6-1 Parts
List
2SB1201-S-TL
p. 8-1
Semiconductor Information
2SB1201 S
p.10-1
Block
Diagram
2SB1202
p.11-2
Voltage Diagram (schematic)
2SB1201
We believe the part is supposed to be a 2SB1201.
Identity of R1271
R1271 on the Main Board is a dry reed relay for switching the SEND signal used to operate
external RF power amplifiers. It's listing varies depending upon the reference within the
Service Manual. We'd love to hear which part is actually in your rig.
p.
6-12
Parts
List
OMR-109F
p.11-4
Voltage Diagram (schematic)
AHY103
The Board Layout on page 9-7 clearly shows that the R1271 has a completely different
layout than either R1111 or R1291, which are identified as AHY103 relays in both the parts
list and the schematics.
We believe the part is supposed to be an OMR-109F.
Page 102 of 113
2003-02-08