[Johnson] Are there " good" modifications ? -yes!
Sherrill E. Watkins
SEWATKINS at dgs.state.va.us
Thu Jul 22 14:28:20 EDT 2004
I would also like to state that I can think of at least two good
modifications to help older tube type equipment. The first is the replacement
of the TV type sweep tubes used in various transmitters/transceivers made in
the 1960's and '70s, with the 6146 or equivalent type. While this may depress
"collector value" for the equipment, it certanly allows one a practical
approach at modest cost for being able to USE the equipment now that sweep
tubes are difficult to find and expensive. If you question this, just try to
find a pair of electrically matched sweep tubes! Also, a second modification
that I agree should be performed is the installation of a time delay relay or
similar device in the solid state power supplies used in the same era
equipment. The purpose being to delay the application of the high voltage for
about 2 minutes to allow the tubes to reach proper operating temperature
before the B+ is applied. This will extend greatly the life of the tubes. -
73 - Sherrill W. k4own
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