[Elecraft] power supply

[Mike Harris]

Hi,

> I am comparing the MFJ 4125 power supply to the Samlex SEC-1223 and
the
> Astrom SS-25. Any helpful comments would be appreciated. This will be
used
> to power a K2/100 eventually.

My SEC-1223 kicks up a din every 25kHz or so on 160 and 80 metres.  The
frequency changes with load.  It seems to be on the output 'cos if I
connect a receiver to it which uses the raw 13.8V I hear a low level
whine.  On the K2 it vanishes when disconnecting the antenna.  Also now
developed a 50Hz mechanical buzz with any load greater than about 5A.
Very irritating in a quiet environment and could replace the need for
sidetone!

My K2/100 draws about 15A at 100W on 10 metres.

Regards,

Mike VP8NO
K2/100 #1400