I suspect something is wrong also but I think it is in the design and not in
any particular component failure. I've done the usual Google search and found
the loading problem is common with this amp. During the search I have found no
fixes to the problem.
This amp had never been powered up when I got it about 3 months ago.. The power
cable had never been connected to a plug and the tubes were still in the
original boxes from Eimac. The relay contacts as far as I could tell had never
been energized and showed no sighs of any electrical contact at the
contacts(that sounded weird), none of the connectors on the rear had any sigh
of a connector being screwed on or pushed on.
There are places on the web that covers a gold sputtering problem with the 2500
and the 8875 tubes due to VHF parasitics and other high Mu tubes for that
matter.
There are others that say they have ran their 2500 for 20 years and had no
problems.
The amp works fine, good output, good reports. So why fix something thats not
broken right? I just want to keep it that way, the tubes are way too expensive
to replace. One good thing about buying something that has been out in the
field a long time is that you get to see what kinds of problems there were with
the design and hopefully fix it before it hits you in the wallet or something
very close to the wallet.
Ken
*************************************************************************
Somethings definitely wrong then.
Id start by closely inspecting the bandswitch and plate choke.
BTW, the cover has to be in place when tuning, the steel that close to the
coil has a huge effect.
Carl
KM1H
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