Model 34, vs 623 - Printable Version

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+--- Thread: Model 34, vs 623 (/showthread.php?tid=7211)

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Model 34, vs 623 - marty - 08-09-2013

Hi All;
As most of you know I am working on getting my Philco 34 running.. I am wondering, since the schematic and documentation show so little in values..
Can I use Philco model 623, for my guide as to voltages on the tubes.. The back end from Dector Oscillator to the Audio Output are almost the same, the 623 has one less IF stage, but other than that it has the same tube lineup..
As, I have used the model 44 on the front end for coil values as the coils and the Selector switch are also the same, the only difference I can see is a cap is in a different place in the circuit..
I also like that the 623 has one less "C" Battery than the 34..
http://www.nostalgiaair.org/Resources/185/M0013185.htm (34)
http://www.nostalgiaair.org/Resources/581/M0013581.htm (44)
http://www.nostalgiaair.org/Resources/806/M0013806.htm (623)
THANK YOU Marty

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RE: Model 34, vs 623 - codefox1 - 08-09-2013

Best to stick to original layout, alignment instructions and repacement component values. This is not a simple set, but should perform well when you are done. Be careful with the filament supply voltage, these battery tubes are somewhat fragile.

You can get a better set of specs and schematics here: (Well worth it!)

http://www.philcorepairbench.com/schematics.htm

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RE: Model 34, vs 623 - marty - 08-09-2013

Hi All;
Codefox, Thank You for your reply..
I wasn't talking so much about changing anything, but, on the Pages for the 34, they just give the plate and Screen Grid voltages, where as the 623 pages, they also give the rest of the voltages for the other grids..
I already have the Pages from Chuck for the 34.. They are a big help in following the wiring, with the schematic page all blown up..
I have set the filament voltage supply at 1.8 Volts just in case, I can adjust it from about 1.6 to about 2.4 volts.. So, 1.8 volts gives me some leeway, before hitting the top threshold, due to spiking when first turned on..
THANK YOU Marty

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