[R-390] 26Z5W Tubes - Other Devices?

[Jacques Fortin]

Hi Alex,
As far as I know, the Tung-Sol (only one manufacturer !) 26Z5W was used only
in the R-390/URR and in the R-390A/URR.
Also, the only substitute I know of (tube wise) is the 12BW4, but you will
have to change the base connections in the related power supplies.
See attached...
There is also some "solid-state" substitutes (Sigmapert, for ex.) but all
depend on how much you are "traditional" or not...
I replaced the 26Z5Ws in my R-390 and I also have a "spare" supply unit for
my R-390As that use the 12BW4s also.


73, Jacques, VE2JFE in Montreal
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