[Elecraft] Samlex 1223 & 1235 power supplies

[Vic K2VCO]

On 5/24/2010 4:32 PM, Jim Brown wrote:
> On Mon, 24 May 2010 13:05:03 -0400, Paul Christensen wrote:

>> Another disturbing attribute of the '7800 and '7700 is that harmonics from
>> its internal SMPS can be heard when the receiver is tuned from ~ 80 kHz
>> through 160m with decreasing amplitude as the receiver is tuned upwards.
>> Oddly, the noise increases as the antenna ports are deselected.
>
> Yet another great feature of a $10K radio. :)

I had an IC-751 that did this. In those days I was naive about switching supplies, and I 
could not figure out what the noise was. At one point I had to send it to ICOM for service 
for another problem, and I asked them to please fix the noise. They replaced a number of 
parts (not connected with the PS) and reported it fixed. Of course there was no difference.

-- 
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco/