I'm running 2x SS-30M and no noticeable noise on 6m EME. They are about 10 years old, not sure if current production is any different. I think the 30A rating is for peaks only, otherwise 25A. 73, Josh W6XU On 11/8/2013 10:45 AM, Mike Dodd wrote: > What about the Astron ASR-SS-30M 30A switching supply. Quiet or noisy?