[RFI] New Astron Switching PS RFI?

[Jim Brown]

On 5/18/2020 11:45 AM, Kim Elmore wrote:
> I also have an old Astron RS-35 (no meters) linear supply. I tossed the Astron regulator board that came with it (very prone to RF) and put in an “RF Proof” regulator board from the 1988 ARRL Handbook. It’s built like a tank and is still doing fine.

A likely cause of the RF issue is that in every  Astron I've opened, the 
foot of the terminal strip to which both V- and Green Wire are soldered 
was insulated from the chassis by paint. This makes the Green Wire and 
V- excellent receiving antennas.

Other than that soldered connection, everything from the DC side of the 
transformer floats, so that V- can be floated. And, in most stations, it 
should be, but the chassis should be bonded to the rest of the station. 
I've scraped the paint in mine, of course.

73, Jim K9YC