08-04-2010, 08:50 PM
Hi Kevin,
Welcome!To the Phorum!
That tone cap or caps wiring isn't very critical. The bottom end can be hooked to ground, the screen grid of the output tube, or the bottom end of the output transformer (at the B+ or HT connection) All will do the same thing. If it is hooked to the SG or transformer you can use a lower voltage rated cap as it won't have all of the B+ on it. On the older Philco sets the tone switch and caps where made together so the frame of the switch would act as the ground connection. The 89 is a great little set and has a rf amp to boot! You may want to have a look at the osc tickler winding. Me thinks that a common problem with that set. There's also a few different versions with different tube line ups.
Terry
Welcome!To the Phorum!
That tone cap or caps wiring isn't very critical. The bottom end can be hooked to ground, the screen grid of the output tube, or the bottom end of the output transformer (at the B+ or HT connection) All will do the same thing. If it is hooked to the SG or transformer you can use a lower voltage rated cap as it won't have all of the B+ on it. On the older Philco sets the tone switch and caps where made together so the frame of the switch would act as the ground connection. The 89 is a great little set and has a rf amp to boot! You may want to have a look at the osc tickler winding. Me thinks that a common problem with that set. There's also a few different versions with different tube line ups.
Terry
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!
Terry
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
