[R-390] Line filter issues?

[Roy Morgan]

At 01:41 PM 8/5/03 -0400, AdamAnt316@aol.com wrote:
>Recently, I have experienced loud buzzing noises on the lower bands of my
>R-390A.  ...  I am getting this noise
>whether the set is turned on or off,


If the radio is turned OFF you still get buzzing sounds? Where are the 
sounds coming from?

>and whether the variac I have the set plugged
>into is turned all the way up or down, with the only cure being to unplug the
>setup completely

If there is no power to the radio and it is buzzing, there may be some 
problem with the grounds and power lines in your outlets.

>  guessing that the line filter is to blame; is there a way to repair it, 
> or does it
>need to be replaced entirely?

The line filter is soldered shut and is filled with goo (I think).  It's a 
chore to get one open and fix things inside.

>  If replacement is the only way, what would be
>best to use to do it?

Replace the line filter with a small piece of metal into which is mounted a 
modern IEC RFI line cord connector. These are the things found on all 
modern computers and other equipment.. Some have RFI filtering and some 
don't.. New prices are very modest, and they can be found at hamfests for 
even less money.

Roy


- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
7130 Panorama Drive, Derwood MD 20855
Home: 301-330-8828 Work: Voice: 301-975-3254,  Fax: 301-948-6213
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