Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

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




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
HiFi (Chifi) tube amp build - but my own design.
Tim, nice write up and thanks for sharing !! Sincerely Richardradiorich — 02:47 AM
HiFi (Chifi) tube amp build - but my own design.
Well, this was a real "Hum-Dinger" :lol: ! This will be kinda long, but hopefully it will help others having t...TV MAN — 01:55 AM
Shadow Meter Bulb
Phorum members, I am trying to find the bulb # for PHILCO Shadow Meter part number 45-2180 that is from a 37-640 chassis...georgetownjohn — 06:53 PM
Philco 41-608 changer coupler
3D-printing...short of machining, of course. Or molding.morzh — 05:20 PM
Philco 41-608 changer coupler
Thanks, Morzh. That solves the issue of the rubber pieces. Now, I need to find a way to replicate the pot metal piec...alangard — 05:07 PM
12' Philco
If it is 12', either Kareem or Andre would have to jump pretty high to look at the front panel. Kareem would have an e...morzh — 01:48 PM
12' Philco
And here's a story about the tires on the truck. Same "no-stoop" guy must have installed these! Take care a...GarySP — 01:17 PM
Hickok AC51 tube tester
I think they have only shown the secondaries of the transformer. Two of them feed the rectifiers' filaments.morzh — 12:58 PM
IF can wire size and Rubber mounts?
Arran If the wire inside cans is the gauges you mentioned, the sole reason for that would be mechanical, to stiffen t...morzh — 12:56 PM
12' Philco
Rod, Yes, I know, but the Giant Philco is not around anymore either, so I go by whoever was alive fairly recently. H...morzh — 12:54 PM

[-]
Who's Online
There are currently no members online.

>