View Single Post
  #4   Report Post  
Old April 21st 11, 09:36 AM posted to rec.radio.shortwave
Kevin Alfred Strom Kevin Alfred Strom is offline
external usenet poster
 
First recorded activity by RadioBanter: May 2009
Posts: 544
Default An actual radio post - Icom R75 tech problem

On 4/21/2011 2:25 AM, wrote:
On Apr 21, 12:42 am, wrote:
Hi - if anyone has any experience with an R75, I would appreciate any
ideas you have. The R75 has several filter settings, narrow-normal-
wide. Until Monday night, they all worked perfectly. Suddenly, on
the AM-wide setting, the signal is enormously attenuated - not
inaudible, but virtually all the gain is gone in that setting. In all
other settings the radio works as it should.

Any ideas? Is this a filter problem, a solder problem, other? The
radio has not received any knocks or spikes I know of. It does have
the Kiwa mods, which means the fault occurs in the 6 kHz filter that
replaces the original 15 kHz filter.

Thanks,
Bruce


If you put a jumper across the filter does the gain come back ?




Excellent suggestion for testing. It's also possible that a bad
connection at the plug-in (if it is a plug-in filter) or solder
points will be flushed out merely by unplugging or jumpering the
connections.

You might want to jumper the in and out terminals on the filter with
a .01 mF capacitor instead of a dead short for the test, just in
case there are DC voltages on the terminals.

With all good wishes,


Kevin, WB4AIO.
--
http://nationalvanguard.org/
http://kevinalfredstrom.com/