[RFI] Quiet Switching Power Supply?

[JW]

The Icom PS-125 comes closest to noiseless that I have found, WHEN they are working right. I have one that emits noise that can be received in places on 160 meters, yet another that is totally quiet. My QW tuned 160 meter vertical loop (40' H x 16' V, about 120' circumference and fed differentially) is 25 feet away from the radio and power supply and AC wiring in the wall. The antenna also 'cuts' across the underground AC mains to the house at about an 80 degree angle    This is on a small city lot. 

The design of the PS-125 includes two commercial ferrite common mode chokes as well as the usual 'line' caps on the AC input side.

de WB5WPA Jim


      From: Jim Brown <jim at audiosystemsgroup.com>
 To: rfi at contesting.com 
 Sent: Thursday, August 4, 2016 12:43 PM
 Subject: Re: [RFI] Quiet Switching Power Supply?
   
So far, I've not found one that meets that description. :)  Last night, 
I posted to Iota's support page on their website asking about EMC with 
their units. We'll see.

73, Jim K9YC

On Thu,8/4/2016 6:21 AM, dalej wrote:
> Unless you're in a screen room or 100 miles from civilization, the background noise is going to cover up any minuscule noise that the best switchers for ham use are going to emit.

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