ICOM IC-201
I'm among those guy's
owning an ancient ICOM transceiver model IC-201. Since this a good, analogue
transceiver for 144-146Mhz there might be some interest to set-up a database
with additional information. There are some known problems with this transceiver
and I like to investigate if there is a base for collecting this information,
since ICOM was not able to help me and others out.
I'll appreciate a response
of everybody owning this IC-201 and have some interesting solutions for other
users.
Known users:
IZ0GYQ-Enrico, PA0JCA-Sjaak, DF1EQ-Juergen, Lars SM1HOW, Guiseppe IK8XFR.
Please contact me at: info@pa0ply.nl

| Modification |
Board
Ident |
Date |
Solution |
| Loud plop during CW-operation |
U69-1 |
14 April 2004 |
 | Remove connection to Q14-collector. |
 | Reconnect Q14-C to +13.8Vdc |
 | Add capacitor, 1000mF to J4-pin1 |
|
| Very strong CW-monitor sound |
U69-2 |
14 April 2004 |
Change R64 into 330kOhm |
| Provide Low Power RF
output (abt. 300mW)-simple
solution |
U74-1 |
14 April 2004 |
Shortcircuit R20 with switch |
| Low Power output, modifying PA
section to maintain S-meter function |
TX-PA |
27 October 2006 |
Remove entire PA section and
remove driver transistor |
| Enlarge freq. range to cover
143.600MHz |
Frontpanel |
|
Change wiring of Course switch S3
as follows:
Relocate yellow wire from S3-1/pos1 to S3-2/pos1
Remove brown wire from S3-3/pos1
See also picture section
|
| CW operation in SSB - mode |
U69-2 |
27 October 2006 |
No need to switch to CW for
sending small CW messages in SSB-mode. |