11-27-2021, 10:53 PM
Hi Allan and welcome,
The 70 speaker is not all that rare they do turn up on epay maybe twice a month. The look pretty much identical to the 20,21,and 90 models also. Electrically some of them the output transformers are different. After 90yrs the cones are brittle and it's probably will need it replaced. The cone is easy to remove just several screws no glue.
If you have an interest I have a 21 speaker but it has no cone, vc, and the opt is open along with the fc. Essentially it's the frame (basket+fc). You can have it for the shipping. I use a shop in NJ to recone and they do the vc and spider too. The fc can be rewound. There has been a couple of guys here that done it. And an opt.
If if get one from epay it could have a open fc or opt.
The 8" pm spkr won't fit properly it's a bit bigger than the original. You'll need the 4pin Philco speaker plug. It's not a 4 pin tube base. A 3100 ohm 20 ohm resistor, 10 and 47 mfd 450v caps. Resistors make lousy power supply filters. Chokes are great! And a se to vc opt.
The 70 speaker is not all that rare they do turn up on epay maybe twice a month. The look pretty much identical to the 20,21,and 90 models also. Electrically some of them the output transformers are different. After 90yrs the cones are brittle and it's probably will need it replaced. The cone is easy to remove just several screws no glue.
If you have an interest I have a 21 speaker but it has no cone, vc, and the opt is open along with the fc. Essentially it's the frame (basket+fc). You can have it for the shipping. I use a shop in NJ to recone and they do the vc and spider too. The fc can be rewound. There has been a couple of guys here that done it. And an opt.
If if get one from epay it could have a open fc or opt.
The 8" pm spkr won't fit properly it's a bit bigger than the original. You'll need the 4pin Philco speaker plug. It's not a 4 pin tube base. A 3100 ohm 20 ohm resistor, 10 and 47 mfd 450v caps. Resistors make lousy power supply filters. Chokes are great! And a se to vc opt.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got it!
Terry
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