Login  Register

Re: Checking KPA relays

Posted by n0jrn on Dec 20, 2009; 5:45am
URL: http://elecraft.85.s1.nabble.com/Checking-KPA-relays-tp4193591p4193799.html

Thanks Don:

Easy enough !           I appreciate that very much.

Yes I am working with my KPA100.  I'm looking for why the K2 drops out of TX
when I try to adjust output above 35 watts.

A couple of the bands are also showing excessive current draw and high
reflected.

Just wanted to check the relays and make sure everything in the LPF first.

I've spent a good part of the evening reading the archives for similar
issues.   Your comments in most cases take folks back to the SWR bridge and
related components.

BUT         first things first !

Have a great evening

Jerry

> I assume you are working on a KPA100 - if not, please ignore.
> The easiest way to check the relays and the LPF of the KPA100 is with an
> antenna analyzer.
> Put the KPA100 to the right of the K2 (upside down on a book or other
> support) with the ribbon cable connected to the K2.  Power only the base
> K2 through the coaxial jack.
> Put the leads of a 50 (ok, 51 will do fine) ohm resistor into the
> connector that normally connects to the AUX RF header.
> Power the K2 on and select each band in turn.  For each band, scan
> through the frequency range of the antenna analyzer to determine the
> cutoff frequency for the LPF - it should be higher than the band edge,
> but lower than the 2nd harmonic.
> If all bands meet that criteria, the relays and LPF are correct -
> assemble the KPA100 to the base K2 and go.

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html