[Elecraft] Power supply for 220 VAC

[Bob Nielsen]

On May 9, 2006, at 7:47 PM, Ken Alexander wrote:

> I'm planning a short DXpedition to a 220V country.
> Does anyone know of a quiet switching power supply
> that would run on 120V 60Hz and on 220V 50Hz?
>
> I'm leaning towards a QRP operation, requiring a
> smaller supply, approx 5A at 12V output.  However,
> since this is likely to be a once in a lifetime deal I
> might take a 100W transceiver and would then need a
> larger supply, say 40A at 12V.
>
> Any guidance would be appreciated.  Thanks in advance.
>
> Ken Alexander
> VE3HLS

The January 2000 issue of QST had a review of several switching power  
supplies showing the noise characteristics.  Several of these not  
only had fairly low noise, but could also operate on both 110v and  
220 v.  The Astron SS-30M, Kenwood PS-40 and MFJ-4225MV look pretty  
good on both accounts.

On a trip to Europe a few years ago I took my K2 with a MFJ-4103.   
This is a small light-weight supply which works on a wide range of  
voltage and seems to be very quiet.  It is only rated at 2.89 amps,  
but was adequate for the K2 even at full output.  Unfortunately I had  
forgotten to bring the removable power cord but since it uses a  
standard computer-type cord I was able to find one fairly easily (I  
operated from the battery for a few hours in the meantime).

73,
Bob Nielsen, N7XY