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Model 87 Tube Substitution?
#1

Newbie here with a model 87 lowboy.

My 280 tube is broken. Is there substitution tubes I can use? The 280 is pretty expensive.
#2

280 is a plain 80, later known as 5Z3. The globe shape of the older 280 is what drives the cost up so high.

GL
#3

Thanks Exray! I still have a lot to learn, but I'm working on it.
#4

I had written an E-mail to Radio Daze about substituting the 5Z3 for my 280 and here is the reply:

We wouldnt suggested the substitution because it draws more amps from the amp - roughly 50% more. They will physically fit though.

Will there be a problem with the draw of more amps?
#5

Possibly - the old original power transformer, now running hotter to begin with at 120 volts on primary instead of rated 110VAC, will possibly overheat with even more stress on the rectifier secondary.

Just use a type 80, which is what the transformer is rated at.

Chuck




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