08-09-2013, 07:16 AM
If your sets have UX (plug-in) sockets, then you should be able to use 30 tubes by reducing filament voltage to 2 volts. Your filament rheostats won't work as designed, though.
In the past, before people discovered that the 1G4 could be used as an 01A substitute and the price of 1G4 tubes went up accordingly, I made up several adapters using old bases of four-pin tubes (with the bayonet pin) and an octal socket on top to use 1G4 tubes in sets like the Freshman Masterpiece. Other than not being able to control volume with the filament rheostats, the subs worked fine. Again, filament voltage has to be lowered to an appropriate level.
In the past, before people discovered that the 1G4 could be used as an 01A substitute and the price of 1G4 tubes went up accordingly, I made up several adapters using old bases of four-pin tubes (with the bayonet pin) and an octal socket on top to use 1G4 tubes in sets like the Freshman Masterpiece. Other than not being able to control volume with the filament rheostats, the subs worked fine. Again, filament voltage has to be lowered to an appropriate level.
--
Ron Ramirez
Ferdinand IN
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