41-285 capacitor help needed!!
Hello everyone!
I am new to this forum! I have re-capped several radios in my collection, including a 37-610. My electronics knowledge is very basic, and I posses no test instruments outside of a multi-meter. I received a Philco 41-285 as a gift this Christmas! It is in beautiful condition and performs very well. I ordered the schematic and technical info from Ron's Philco web site, and am now ready to begin a re-cap of all the electrolytic and film capacitors. My problem is that the capacitors in the radio and those shown in the manual do not match. The radio has had the AC transformer replaced and several of the capacitors a long time ago. The repair was very well done. Here is a list of the capacitors in question:
Capacitors in radio now-------------------Capacitors shown on schematic
49. .002 mfd @ 1000 V-------------------49. .003 mfd @ 1000 V
45. .002 mfd @ 1000 V-------------------45. .001 mfd @ 400 V
33. .002 mfd @ 1000 V-------------------33. .05 mfd @ 200 V
55. Not in radio at all---------------------55. .01 mfd @ 400 V
57. Not in radio at all---------------------57. .002 mfd @ 400V
62. 16 mfd electrolytic--------------------62. 12 mfd electrolytic
All other caps in the radio are original, and match the schematic. My question is should I re-cap according to what is actually in the radio, or change it to match the values shown on the schematic? Any help or advice will be greatly appreciated!
Thanks to all in advance!
Posts: 13,776
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State, Province, Country: Indiana
Hi Kevin, and welcome.
I hope you ordered the schematic and service info from Chuck Schwark's web site...I do not sell schematics. You will be pleased with the info you receive from Chuck.
I only see a few production changes in this model, and the info you get from Chuck will include all of this. Nevertheless, for now let's discuss a couple of these.
Resistor (41) was changed from 33K, 1/2 watt to 100K, 1/2 watt.
Capacitor (45), .01 uF (not .001) was changed to .003 uF.
You should recap to match the schematic, with the two exceptions noted above.
The radio would work without capacitor (57), but you should put one back in.
The radio will not work as well without capacitor (55). Without this capacitor, one of the Type 41 tubes will not be receiving any audio signal. Be sure you reinstall this one.
I hate to tell you this, but you have the Philco chassis that is, in my opinion, one of the most difficult Philco chassis to service; the others being the 41-285's siblings, including Models 41-250, 41-255, 41-280, 41-287 and 41-290. Not because of the capacitor replacements; but because of that crumbling rubber insulation on the wiring. That insulation should be replaced for safety and reliability. This is not a job for a novice; it will be difficult, and time consuming. Beware especially the wiring attached to the band switch. This is the hardest part.
Good luck.
--
Ron Ramirez
Ferdinand IN
Ron,
Thank you so much for your quick reply to my post. The information you provided was very helpful! I have since discovered that several items in my original post were incorrect. First, yes I did order the schematic information from Chuck's web site, not yours! The information was invaluable in helping with my restoration! Second, the missing capacitors that I listed were not missing at all! The capacitors shown on the Philco chassi illustration and parts list, and those found in the radio itself did not completely match. This led to confusion on my part. Upon closer inspection I discovered that the only capacitor missing form my set is the #33 capacitor found on the parts list and illustration near the 7A6 tube, but not found on the schematic. Well I followed your advise and replaced all of the film and electrolytic capacitors according to the schematic. I also replaced many of the rotten rubber wires. When I turned the set on it had low volume and was not very sensitive. I went back over all of my work I found it to be correct. I decided to see if I could improve the set's performace by attempting to align it. I do not have a signal generator or vacuum tube volt meter. I carefully followed the alignment instructions that I got from Chuck as closely as possible. Well the old girl came fully to life! The sensitivity and audio level is now very impressive! The dial also tracks very closely! The radio is now a real joy to operate! Now all that I need to do is replace a bit more of the old wiring. Thankfully most of the wiring in this radio is still in good shape. So thanks again for all of your help in bringing this wonderful old radio back to life! I am sure that I will enjoy it for many years to come! Thanks also for providing this excellent web site! Reading the posts provided me with a lot of helpful information!
73,
Kevin
Posts: 717
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Joined: Feb 2008
City: Grand Rapids, MI
Ron Ramirez Wrote:I hate to tell you this, but you have the Philco chassis that is, in my opinion, one of the most difficult Philco chassis to service; the others being the 41-285's siblings, including Models 41-250, 41-255, 41-280, 41-287 and 41-290.
Good luck.
I wish I'd known this last June when I got my Philco 41-255, but I got a really good deal on it and it's in pretty nice shape for its age.
Mike
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Kevin
Excellent news. Enjoy your radio!
Mike, this is why I try to stay away from these models. Just too time-consuming to mess with, in my opinion. I have to admit, though, that they are nice performers when properly restored.
--
Ron Ramirez
Ferdinand IN
Posts: 717
Threads: 30
Joined: Feb 2008
City: Grand Rapids, MI
I believe I'll save the '255 for a later effort. Probably be a bit much as an inaugural project. ![Icon_lol Icon_lol](https://philcoradio.com/phorum/images/smilies/icon_lol.gif) Ha, listen to me. 53 years old and I'm the rankest of beginners with almost zero knowledge. Only time I actually fixed a radio was back in summer 1971 when I replaced a filter cap in a Philco, I think it was a 42-345, and even then I didn't solder it in. But by gosh it worked where it only hummed before. But everybody's got to start somewhere and sometime. Forgive me, I know not what I'm doing.
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