[Elecraft] Elecraft CW Net Announcement

[Tom Hammond]

Bert:

>BTW, do you (or does anybody) know of a true regulated "wall-wart" 
>suitable for the K1. When I first powered up with a Radio Shack wall-wart 
>last week, I heard a noticeable hum along with the sidetone. A quick 
>e-mail exchange with a super helpful Gary Surrency and a Radio Shack 3 amp 
>regulated power supply was swapped in. Hum gone.
>
>I plan on travelling to Ecuador this summer and plan on taking my K1 with 
>me. If there are no suitable wall-warts, I might as well buy the PS down 
>there as there are plenty of Radio Shacks down there and the prices are 
>pretty much the same. (Checked out the HTX-10 year before last.) Thanks 
>for any advice.

Were I you, I'd look into something a bit more 'sturdy' than a mere wall 
wart. Something that'll put out 1A-2A without complaint. You'll have a 
better chance of improved voltage regulation and better filtering as well. 
Maybe an in-line power supply like those offered with many laptop PCs. They 
generally supply 12-14VDC @ 1A-1.5A and I've had very good luck with 
them.  MANY put out 15VDC (reg.)  at up  to 2A. If you place a couple 2A 
silicon diodes in series with the positive side of the line, you'll wind up 
with the output voltage MINUS 1.2VDC ( drop thru the diodes) = 13.4VDC 
which should be great for the K1. In fact, IF the P/S puts out 15VDC, a 
SINGLE diode would provide 14.3 VDC which would be even better.

For regulated output LINEAR (no-RFI) in-line supplies, look at Jameco part 
numbers 229016CA and, 206471CA.

For regulated output SWITCHING in-line supplies (2-wire AC input), look at 
Jameco part numbers 221840CA and 211174CA.

For regulated output SWITCHING in-line supplies (3-wire AC input), look at 
Jameco part numbers 221815CA and 215124CA.

Some (though not all) switchers can generate a bit of RFI (some more than 
others, YMMV), but this can often can be mitigated by using antennas which 
get the feedpoint well away from the radio... e.g. coax-fed and 50' or so 
from the rig.

73,

Tom Hammond    N0SS