Alfatronix in UK does make very silent switch mode PS. This is excellent down to 500 kHz w/o any noise. I use 9A version with the K3/10. The 3A version is good only if you do not the second RX. They have 20A version for 100W trx as well, but that one a bit expensive.
73, István On 9/14/2011 11:03 PM, David Dunn wrote: > Re:] Switch mode PSU > > I just read the comments and reply in the message below: > I have both those PSU, the Sec 1223 is by far the oldest one. It has > several" birdies" best described as rather Raucous Crows, which get worse > as the frequency goes lower. 160m is pretty poor. I added several devices > in attempts to quieten same, which was achieved to some degree. It is > acceptable on all but 160m, where it appears in about 3 places across the > band, (not always the same places) The Waters and Stanton Power Mite is > cheaper device and does much the same although trips off when the full 20 > amps is drawn quite often. It has similar noises on several bands, which I > can live with but is about the same as the other on 160. I have not > attempted to add filters due to the limited success of the other. There is > little doubt the "proper" transformer PSU's I have are best but where > weight is concerned the switch modes units are light and neat for the cost. > - Ideal I guess for the VHF folk > > 73 David G3SCD / VK3DBD > _____________________________________________________________________ > > Message-ID:<[email protected]> > > > Iain, I use a Power Mite from Walters& Stanton when not in the shack - is > very quiet, both physically and RF wise > 73 de M0XDF, K3 #174, P3 #108, KX3 #??? > > -_______________________________________________________________ > > > On 10 Sep 2011, at 22:58, Iain Haywood wrote: > >> Hi, >> >> Has anyone had any bad experiences using a K3 and a switch mode PSU?. >> The SEC-1223 looks great aware some can cause problems.. >> They say 'Totally noise free', that's some claim.. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
