Courtney and all,
Courtney Krehbiel wrote:
...The real cause of my trouble was dead 1N5711 diodes in the internal SWR
bridge circuit. The diodes in both the KPA100 and KAT100 were fried...
> With the RF detector circuit dead and
measuring no output power, the K2 feedback control process just kept
trying to drive the unit harder until it reached full bore and
high-current would ensue...
I had exactly this problem a few weeks ago. In my case, though, it
seems a near lightning strike (in winter!) or some other ESD source
zapped just one of the 5711s in the bridge. But after that 3 diodes in
the t/r switch shorted, followed by scorching a few resistors in the PA
area as well as one in the t/r switch. Ouch.
With Gary's patient help as well as a few component replenishments from
Scott ([EMAIL PROTECTED]) I was back in business again. My lesson learned
is disconnect the antenna even in winter time. It still feels good to
have the rig working again!
73,
Mike ab3ap
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