My L4 used Amperex 3-500Z tubes. When used at the power level in the drake
manual and the Drake tune up procedure, did not show any color except at long
key down at I kw input. The manual said they are not to show color. The L4 was
made for a short time before the L4B . The L4 is much rarer. The ability to
see the tubes causes problems for the mind. Think of the poor tubes in the
Jason Buchanan <email@example.com> wrote:
> I just sold my L4 and anything key down at or over 1kw input caused the
> plates to glow very orange.
same here - 3-400Z idle on SSB mode causes them to get dull orangish.
Sometimes I wish I had some of the new 3-500Z graphite jobs but the fan just
isn't up to snuff to keep them alive.
73 Jason N1SU
Jason Buchanan - Boxboro, MA
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