Philco G1909S Need info to help with Restoration
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I have a Philco G1909S which was purchased by my wife's grandparents in 1959. I am planning a restoration and am assembling a shopping list.
I have found the circuit diagram for the amp, but have not had any luck finding info about the tuner circuit. The tuner circuit is a Model RT-202-3. I found a page from PR-3262 that states that service info for this circuit is in document PR-3263. I have no idea where to find this document. I am trying to determine what parts I should replace as well as any alignment procedures for the tuner.
As far as the power amp, I am planning on replacing all the electrolytics and the B+ filter cap before I turn it back on. Are there any other components I should consider replacing? Should I replace the components in the crossover circuits in the speakers? Should I be worried about the selenium rectifier getting trashed by new caps? I plan on matching existing capacitor values to reduce stress on rectifier.
Everything seems to be in fairly good shape, with the exception of 2 missing knobs. The record player works and audio sounds pretty good, but once everything heats up, audio output gets reduced dramatically. Is there anything I should be checking that may cause this sypmtom other than capacitors? I also plan on cleaning all tube sockets and potentiometers.
This is my first experience with Philco radios, so I have lots to learn!
I would really appreciate any help or advice.
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Welcome to the Phorum!
Here's the Philco Gallery info on that set: http://philcoradio.com/gallery2/1959a/#M...honorama_V Photos of your set would help fill out the gallery.
Looks like Steve Johnson has both original service info and Sams Photofact info for that set: https://antiqueradioschematics.org/index.html I've bought a schematic once from Steve...transaction went fine.
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If audio goes down you might check your tubes.
As for replacements, the ceramic and mica caps should be left alone, just replace the tubulars.
And obviously the electrolytics.
Check the resistors for the common sense accuracy, 20% tolerance is ok.
Other than that.... that's it.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Found your tuner here: http://www.rsp-italy.it/Electronics/Radi.../index.htm
Click on 1959 and goto page 109.
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!
Terry
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I uploaded some photos of my radio for the gallery. I am still making a shopping list of all I am going to replace. There are a LOT of paper caps in that amp! I think I am going to need to replace all but 4 capacitors in the amp, and about 1/3 of the capacitors in the tuner. I just recapped one of my old guitar amps last night and it made a world of difference!!! I used to hear local broadcast FM stations and tons of hum when the amp was on, now it is almost dead quiet! I am really looking forward to getting my Philco done. Is there anything I need to replace or service in the turntable, i believe it is a model M-41? Thanks.
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Posting picture so everyone can have a look at this project
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If the caps aren't mica caps, then why would you leave ANY OF THEM in the unit that were installed new in 1959??? ESPECIALLY the ones that are difficult to get to. "You're just asking for it", as they say... 
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Are you saying I should replace the ceramic caps too?
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I think since you mentioned paper caps, that is what was meant.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Quite right. Sorry. Stuck the old foot into the mouth again. My bad.  
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Ths is fine, foot in mouth replaces blue cheese but with no added calories.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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The ceramic disk capacitors, like molded micas, can go bad sometimes too, but it's rare, although the earlier production disk caps were more prone to failure then later ones. In a Philco from this era I would pay close attention to the carbon comp resistors, they did not exactly use ones of the best quality, and they are starting to cause problems now.
Regards
Arran
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Thanks for the advice. When you mention the carbon resistors, do I just check their value? Or am I looking for mechanical failure? What kind of failure mechanism are people seeing with them? I want to do this right, but don't want to create more work and cost than is necessary. Thanks.
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You are checking the resistance value of the carbon composition resistors. They generally tend to drift up to higher resistance value with age. Some folks will replace all of them as a standard practice but many only replace the ones that are greater than 20% above spec. You can often check the value while the resistor is still in the circuit but if there are alternate current pathways you will need to detach one end of the resistor and measure. Occasionally they will fail with a complete open but usually its just a higher value than spec.
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