[Elecraft] New Astron Switching PS RFI?

[Jim Brown]

On 5/18/2020 11:38 AM, Josh Fiden wrote:
> These SS-30M supplies have been around a long time. Do others report RFI problems?

Josh, Bob, and all,

I have no experience with Astron SMPS, and have seen nothing. I do, 
however, own several no-name switchers advertised as quiet that are 
quite noisy.

My question was techie-rhetorical. We should not trust ANY reports that 
xxx product is RF quiet unless we know a LOT about proximity of noise 
source to antennas, the sum all of the other noise that could be 
obscuring it in the observer's receiver, and that info for ALL ham bands.

A meaningful test would be waterfall plots from an SDR with a small loop 
antenna that can be placed in proximity to the potential noise source. 
This doesn't require lab-quality testing, simply a waterfall covering 
the frequency range of interest. Prior to the availability of 
inexpensive SDR RX, I've used (and still do for some applications) the 
broad coverage RX in my VHF/UHF talkie.

73, Jim K9YC