03-26-2018, 11:56 AM
Philco's 8" spkrs are a bit smaller than 8" like 7 3/4. They are not a standard size, an 8" replacement spkr won't match up with mounting holes. The 650 is a horse of a different color as it's much easier to service and it does use Philco's Super Class A output stage w/ triode connected 42's and a 42 driver. This offers a very low distortion output. The output impedance for this set up is some what lower than the conventional pentode connected 42's or 6F6's. It's about 5.9K total.
Tech tip. You may want to check the interstage transformer (42 to the 42's) as it is a common issue for one side or the other to be open.
GL
Tech tip. You may want to check the interstage transformer (42 to the 42's) as it is a common issue for one side or the other to be open.
GL
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
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
