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Philco 30-4003 Tone Control info needed (19B Code 123) - Printable Version

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Philco 30-4003 Tone Control info needed (19B Code 123) - hunter2115 - 01-18-2014

Does anyone have any info on the 30-4003 four position tone control? Im trying to finish up a 19B Code 123 and cant find any info on this control. It seems that little info exists, so I would also like to hear from others who have figured the cap values and wiring on your own.
Any info is appreciated!!

RE: Philco 30-4003 Tone Control info needed (19B Code 123) - BrendaAnnD - 01-18-2014

That information should be on the schematic. Philco was very good about that. Generally, it will show the capacitors in the plate circuit of the output tube, with values along side of the caps.

RE: Philco 30-4003 Tone Control info needed (19B Code 123) - hunter2115 - 01-18-2014

No such luck. the 19B is one of those oddballs that Philco changed up parts several times during the production runs.
http://www.philcoradio.com/tech/19evol.htm
Code 123 is really vague. I believe I have the March 15, 1933 version.
I have Chuck Schwark's info pack for the 19/89. It has a parts list showing part no 06764 as the TC. Mine is clearly stamped 30-4003.
The folks with the reference books say that all that is given for this control's values is "X".

RE: Philco 30-4003 Tone Control info needed (19B Code 123) - codefox1 - 01-18-2014

Please post relevant portion of schematic if you have it. Most tone controls were just shunts to mute high frequency response, and values are fairly predictable. If this is across the primary winding of the output transformer, high voltage substitute capacitors are a must, say 1000 VDC or better. If the switch itself is not repairable, you can usually adapt a potentiometer to do the same thing.

RE: Philco 30-4003 Tone Control info needed (19B Code 123) - Ron Ramirez - 01-18-2014

If you'll look at the schematics on the link you provided (from this site):

http://www.philcoradio.com/tech/19evol.htm

and click on the small schematic for 19-123 to enlarge it, the schematic shows the part values for the tone control caps. I have rebuilt many 19 sets using these values and can confirm that they work well.

RE: Philco 30-4003 Tone Control info needed (19B Code 123) - hunter2115 - 01-19-2014

Youre right- thanks Ron! I didnt pick that up before.
Just curious though, wonder why they show part #52 for each of the two caps and part #53 for the tone control body?
Hard to see some of this stuff without a parts list.

RE: Philco 30-4003 Tone Control info needed (19B Code 123) - hunter2115 - 01-19-2014

Done. A .03 and a .05. Sounds really good.
Getting the tone control body out ranks right up there with getting at the caps under the RF deck on 37 models though!