Switching power supply noise
 

On Sun, 29 May 2005 09:17:03 GMT, Justín Käse
wrote:

Am considering getting the Icom PS-125 supply for a 756pro3,
are there any issues with switcher noise on the low bands with this
supply?
Currently my Alinco DM-330MVT produces some rather strong birdies on my
706mk2g in the AM broadcast band and to a lesser extent on up into 80
meters. It has a freq adjust pot that will move the noises, but the Icom
supply doesn't mention having this capability.

There's a review of that power supply at the ARRL web site for QST
product reviews, if you're a subscriber...

bob
k5qwg

"Justín Käse" wrote in message
news:42998624.5306058@chupacabra...
Am considering getting the Icom PS-125 supply for a 756pro3,
are there any issues with switcher noise on the low bands with this
supply?
Currently my Alinco DM-330MVT produces some rather strong birdies on my
706mk2g in the AM broadcast band and to a lesser extent on up into 80
meters. It has a freq adjust pot that will move the noises, but the Icom
supply doesn't mention having this capability.


I have the ICOM supply plus two ASTRON switchers running here.
No noise 40M - 70cm.
I don't operate 160 or 80 right now, so cannot comment on those bands.

--

... Hank

http://home.earthlink.net/~horedson
http://home.earthlink.net/~w0rli

On Fri, 03 Jun 2005 19:53:16 GMT, Justín Käse
wrote:

In posted on
Fri, 03 Jun 2005 19:02:12 GMT, Bob Miller wrote:

On Sun, 29 May 2005 09:17:03 GMT, Justín Käse
wrote:

Am considering getting the Icom PS-125 supply for a 756pro3,
are there any issues with switcher noise on the low bands with this
supply?
Currently my Alinco DM-330MVT produces some rather strong birdies on my
706mk2g in the AM broadcast band and to a lesser extent on up into 80
meters. It has a freq adjust pot that will move the noises, but the Icom
supply doesn't mention having this capability.

There's a review of that power supply at the ARRL web site for QST
product reviews, if you're a subscriber...


Thanks, not a subscriber, but maybe I can find it archived somewhere.
What did it say about the switcher noise issue, or did it address that?

The cutline under one graph of RF noise read:

"This supply exhibited low levels of broadband noise. The most
prominent peak appears between 4 and 7 Mhz."

And in the conclusion of the text:

"According to ARRL lab tests, it is at least as quiet on the HF bands
as other comparable switching power supplies on the market."

This was a Sept. 2002 review in QST.

Bob
k5qwg

On Sun, 29 May 2005 09:17:03 GMT, Justín Käse
wrote:

Am considering getting the Icom PS-125 supply for a 756pro3,
are there any issues with switcher noise on the low bands with this
supply?
Currently my Alinco DM-330MVT produces some rather strong birdies on my
706mk2g in the AM broadcast band and to a lesser extent on up into 80
meters. It has a freq adjust pot that will move the noises, but the Icom
supply doesn't mention having this capability.

JK-

I got the PS-125 with my 756 Pro 2. I also have Radio Shack and MFJ switchers.

When receiving with a magnet-mount antenna mounted a few feet away on the
washing machine, I can pick up a low level noise from the PS-125. The
MFJ, which has a good reputation for low noise, is noticeably worse. The
Radio Shack switcher is a total wipe-out.

I don't recall what band I was receiving. I doubt there would be any
perceptible noise from the PS-125 (or the MFJ) when using an outdoor
antenna.

73, Fred, K4DII