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42-365
#76

(12-08-2016, 07:31 PM)ccbaker13 Wrote:  The voltage on the first XXL tube, pin 2 is 39V. On the second XXL tube pin2 is 146 V (that was the steady value after drifting downward for a time). These values are measured with the black lead touching the chassis.

Perhaps I need a little clarity Lets called the XXL closest to the IF transformer the Mixer tube and the XXL at the end of the chassis the Oscillator tube, these are the functions they perform.

So currently (a little electronic pun there) the voltage on pin 2 of the mixer tube is? And the voltage on pin 2 of the oscillator tube is?

Just want to be sure that where on the same tube rather than calling them the 1st or 2nd tube.

OBTW if you want a schematic that is easier to read (Rider's is awful and the philco service info not that great either) the 41 model 41-260 or 265 are very close to what you have.

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
#77

Yes sorry about that. The voltage at the mixer tube is 150 V (after warming up). And the voltage at the oscillator is 43 V. Note these new values. I will admit this. I noticed I had a 4700 ohm resistor connecting pin 7 and 6 of the oscillator last night instead of 47,000 so i corrected that (its hard to tell orange from red I guess). But the radio has not changed.... .I get no stations. Same problem. So the voltage on the oscillator is still low.
#78

Thanks for the tip on the schematic! Yeah this one us bad.
#79

Looking at the schematic for the 41-260 helps me a lot. Thanks again.
#80

That oscillator voltage is still low. I'm confident that all other resistors and caps that I replaced are the correct values.
#81

So what is a strong station in ur hood?? 'MAL pretty strong?

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
#82

The strongest station here in the DC area is ESPN 980. But I can always get several at night, all the way to WBZ in Boston, my home town. 'MAL is 630? I think that's fairly strong. I also have a home built AM transmitter from a kit that I use all the time with my IPOD and I didn't pick that up either. That's loud and clear on my other radios. My gut tells me this does have something to do with the funky antenna or the band switches. I don't know.
#83

Check to see if you replaced the 47k resistor in the grid circuit of the oscillator w/a 4.7k. Clean bandswitch and pushbutton switches with Deoxit. Do not power up the set till the Deoxit is dry sometimes contact clean can set your bandswitch on fire. You can use a hair dryer  or heat gun to expedite the drying process. Check for misaligned contacts on switches and burn marks (carbon traces).

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
#84

Ok I'll check these things tonight and clean again with Deoxit. Thanks again.
#85

I cleaned the band switch well and made sure I have the 47K Ohm resistor in the grid circuit of the oscillator. Nothing. Maybe its time to give up on this.
#86

The Philco 077 signal generator arrived today. Its completely original. Very nice.




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