[Elecraft] Switching power supplies...yet another comment

[Vic K2VCO]

Two Field Days ago I brought along a little clip-on lamp. It was small, bright and very 
convenient. Its 12v bulb was powered by a tiny switching supply.

It was only turned on for about a minute. Now I call it the Hissing Lamp from Hell. I 
don't know if it also generates the usual unstable noise vortices that roll around the 
bands, but it does produce a loud wideband hiss that sounds like nothing as much as the 
noise generator that I use to adjust my K2's filters. In fact, I could use it for that 
purpose.

Cheap switching supplies: really bad technology whose time has come!

On 7/19/2010 8:15 AM, Jim Brown wrote:
> On Sat, 17 Jul 2010 12:47:44 -0400, John Ragle wrote:
>
>> But...my overall
>> opinion is that switching power supplies have taken a bad rap.
>
> There are switching power supplies and there are switching power
> supplies. Not all are created equal. If you go to an electrical
> supply store to buy a transformer to run 12V lighting, they will
> sell you a switching power supply that is a holy terror. They call
> it an electronic transformer. Ask them for a real transformer and
> you get a blank stare.
>
> Most wall warts that provide DC power for battery charging, or to
> run consumer electronics of all sorts are switching power supplies.
> Many of them are quite noisy.
>
> 73, Jim Brown K9YC


-- 
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco/