[Johnson] Valiant mod query
Glen Zook via Johnson
johnson at mailman.qth.net
Thu Jul 16 10:22:44 EDT 2015
It is definitely possible to do this conversion. Heath did this for the original DX-100 with the MK-3 modification kit and I have seen this done in examples of the WRL Globe Champion 300, 300A, 350, and 350A.
The instructions for the Heath MK-3 kit are included in the article at the following URL:
http://nebula.wsimg.com/a299627e256e4c19a81224d1bd62bb46?AccessKeyId=5DDC3F25F0398F58962E&disposition=0&alloworigin=1
I would use a 3, or 4, section broadcast variable capacitor (nominally 365 pf per section) as a minimum. It has been my experience that such a broadcast variable works fine as the loading capacitor for transmitters with up to at least around 300-watts output. Transmitters, with higher power output, sometimes need plate spacing a little wider to prevent arcing under high SWR conditions. Glen, K9STH
Website: http://k9sth.net
From: John Neeley <w6zkh at att.net>
To: "johnson at mailman.qth.net" <johnson at mailman.qth.net>
Sent: Thursday, July 16, 2015 8:50 AM
Subject: [Johnson] Valiant mod query
Since I am unable to locate and replacement for the Aux Coupling Switch (SW6) for the Valiant, I am wondering if anyone has every replaced that switch and caps with a variable cap in its place? Somewhere I have heard of it, but never any details, i.e., size, capacity of variable, etc. Or, am I just wasting my time and just junk this rig? Even as it sits, I can still use it, but not loaded to full output... Any ideas would be appreciated.
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