[Amps] Water cooling. Not dummy load.

Paul Christensen w9ac at arrl.net
Thu Feb 25 12:41:32 EST 2021

> "Some good images of the amp, inside and out, including close-ups of the
cooling tubing connection to the tube etc. can be found here..."

Those are photos of my 70V amp sitting on the shack floor, right after an
annual water purge back around 2010.  It still hauls in the mail here at
least once a week.

As I recall, the photos were taken after purging.  A gallon of "brand X"
distilled water was purchased from a Local Walgreens.  To this day, I swear
it was branded tap water as the HV leakage reading was off-scale.  Multiple
fill/purge cycles with Zephyrhills-branded distilled water fixed the

The plate choke was recently swapped out for an RF Parts RFC-3 to allow WARC
coverage.  160m was added around 1998, shortly after acquiring the amp from
the owner of Palmer-Johnson Yachts.  Mike, K9MK owns one that's equally as

Paul, W9AC  

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