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Philco Model 52GC - Printable Version

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Philco Model 52GC - slford310 - 06-18-2023

OK Philco fans, I've been working on getting my 52 GC up and running finally.  Have not touched the clock part yet.  I picked up another 52 chassis on Ebay a while back and got the IF Transformer I needed.  Got the chassis up and running last night, then I followed the instructions for the alignment and now nothing.  Anything special about doing the alignment on these other than they are 175KC ?   Racking my brain and it's starting to hurt LOL.

Thanks

Sam

RE: Philco Model 52GC - morzh - 06-18-2023

You mean, it was singing before alignment and stopped after?

If yes, and by chance you removed a grid cap from some tube to inject IF signal, and maybe forgot to put it back....

I do not see what else you could do.

Or is it something else?

RE: Philco Model 52GC - Radioroslyn - 06-18-2023

Agree with Mike I don't understand what "nothing" means? Please explain.

https://philcoradio.com/library/download/service%20info/service%20bulletins/Philco%20Service%20Bulletin%20114.pdf

RE: Philco Model 52GC - slford310 - 06-18-2023

Yes, and sorry, after the alignment no sound. It was singing prior. I'm sure I replaced the grid cap lead after working the IF Transformers. I will go through it again now to see what's up and give an update.

Thanks

Sam

RE: Philco Model 52GC - slford310 - 06-18-2023

So slight change.  Went through the Alignment procedure again and now I get low volume sound out of a couple of strong stations.  Frustrating LOL

RE: Philco Model 52GC - morzh - 06-18-2023

Alignment is a fairly benign procedure: if you simply peaked the IF, which radios prior to alignment are usually more or less close to and this is why they sing, then you ensured there is still IF path and the audio is working.
Short of accidentally disconnecting the RF stage, (and in your case with a 24A tiube being both the oscillator, RF and the mixer, so I am not even sure the grid cap needed to come off) I cannot see why it would stop singing.

See if you had to disconnect things prior to feeding the generator's 175kc signal to the grid cap.

RE: Philco Model 52GC - slford310 - 06-18-2023

So, issues appear to be with me or my equipment.  After following the alignment procedures again, I find a slightly auditable signal at the high end of the band.  I went back to the IF Transformers and adjusted them just based on the sound output and started to hear a better output.  I have the high end and midrange sounding ok but very low output at the     low end of the band.  Again, not sure if it's me, something in the radio or my equipment.  Frustrating  Ahhhhh  :-)

RE: Philco Model 52GC - Radioroslyn - 06-19-2023

Ok so here's plan B. Ground the connection @ the volume and # 34. This sets your IF amp @ full blast. Set your signal generator @ 175kc 400cy tone. Connect it to the grid cap of the "osc 1st det" 24A tube. Adjust output of generator so you can just ear it. Peak the IF adjustments #15, 17, & I think 7. Keep going back and forth till you get maximum sensitivity @ 175kc. Radio dial setting should no effect on the IF adjustment. As the signal gets stronger keep turning the generator output down. Unground #34.

Once that is done check the oscillator to see if it's running and tracking. Set the dial @ 550 and use a well calibrated receiver listen for the osc @ 175kc + 550KC = 725KC. Should should hear around 725KC @ the low end and @ 1500KC + 175KC= 1675KC. You can wrap a few turns of wire around the 24A tube pickup the signal and couple it to the calibrated receiver.

Next step would be to check the resistance of the windings on the ant coil. Don't do it w/volume control in the circuit, can give a false reading.

GL

RE: Philco Model 52GC - slford310 - 06-19-2023

Thanks for the idea above. I will try it next, just not sure If I'll get back to the bench before Friday. I'll let you know what happens.

Sam