[Elecraft] A Final Thanks and Farewell for a While

[John Webster]

Hi List:

Job done.  Well, at least the essentials done.
This will be my last post until mid September,
as I fly out today for the UK for three weeks,
and then on to Zambia (Central Africa) till
September 18.

I will have my newly completed K2 #3290,
and an assortment of options to play with.

Thank you to all who helped make it possible.

As promised, three quick comments on issues
I raised, and the choices I have made.

1. Thank you for the information on adjusting
the output voltage of the Astron RS-35A.  It
is pretty straight forward, but since I don't
need it done immediately it was one of the 
things I have put off doing until I get back.
I am certainly NOT taking it with me :)  If 
anyone still needs the info, I'll report to the
list.

2. I've come to the conclusion that all
switching power supplies generate RFI.  It's
just physics.  Some are certainly worse than
others, and all effects vary according to band,
and over time.  I definitely had a defective
Samlex 1223, the second one was much better
but not perfect by any means.  White broadband
noise obliterated 10meter, was annoying at 12, 
decernable at 15 and pretty much gone below 
that.  But by the time we got down to 80 we had 
S9 "birdies" and other loud squeals at regular 
intervals.  By now I could determine definitively 
if the noise was coming from the PS since I had 
the internal battery in circuit.  Switching instantly 
between them, really showed up what was 
happening.

The Astron SS-25 was better, but not perfect either.
I could detect no white noise anywhere (the worst
RFI situation), no birdie type "signals" on 80m but 
an occassional, very characteristic, rough note or whistle
that would wander around the frequency.

Both were easily adjustable for an output of 14 plus
volts for the purpose of floating the K2 battery.  In 
the Samlex 1223 it an easy to find pot, VR2.  In the 
Astron swicher it is the only pot, a neat high precision 
"calibrated" instrument :)

Despite the not insignificant size and weight advantage 
of the 1223 I've gone with the Aston since it puts out 
less noise.  Of course, many of you commented that you 
have experienced NO noise at all with this or that PS.  I
believe you, but field conditions often call for the kind of
situation I have put them through.

Again thanks and hope to work some of you from across
the pond, perhaps?

73

John, N6JW
G/N6JW and 9J2/ZS1WN or 9J2/N6JW or 9J2xx
for the next while.