Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Philco 40-120 Domino Capacitors
#1

   
I have a 40-120 Philco radio that has been in my grandparents house for at least 70 years.  It has 2 Aerovox Domino style Capacitors with the 3 dots in the arrow Green, Orange Green.  I looked this up and everything I find said this would be 535mmfd aka pf.  The schematic shows 110mmfd.  I thought maybe someone had replaced it with an incorrect capacitor.  I purchased 2 40-120 Chassis from different venders on ebay and both of these also have the Green, Orange, Green domino aerovox capacitors.  One goes between the volume control legs.  The other goes from the volume control to the OP pin on tube 7c6.  What am i missing?        


Attached Files Image(s)
   
.pdf Part45-Philco 1940 RMS Year Book.pdf Size: 1.04 MB  Downloads: 111
#2

Quote:What am i missing?
   

The lead wire on the left Icon_lol 

This cap will affect the high frequency audio as well as clip spikes from static. It will also aid in the reduction of "tweet", that is the high pitched whistle from an adjacent carrier. Indirectly, the cap will save the output transformer...

The "mod" may have been at request of the user for any/all of those reasons.

Use the schemas 110pf, see how it sounds, if harsh a 330,470 or 510 will suffice, it is not critical. Use a silvered mica as a mush-a-lized yellow cap doesn't come in that small a valueIcon_wink

If your a stickler for authenticity I may have all those values in NOS mica, Aero, Cornell, Elmenco.

Fair warning, can't get so cavalier with mica's in the RF section, no mica twisting as that will cause another handicapped cap Icon_rolleyes Buy that cheap plastic dental mirror to look around corners...

Chas

Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
#3

I believe I read somewhere that either Philco or one of the capacitor manufacturers had their own color code scheme for these caps for a short time. You'd think that by 1940 they would have seen the light.




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
Shadow Meter Bulb
Phorum members, I am trying to find the bulb # for PHILCO Shadow Meter part number 45-2180 that is from a 37-640 chassis...georgetownjohn — 06:53 PM
Philco 41-608 changer coupler
3D-printing...short of machining, of course. Or molding.morzh — 05:20 PM
Philco 41-608 changer coupler
Thanks, Morzh. That solves the issue of the rubber pieces. Now, I need to find a way to replicate the pot metal piec...alangard — 05:07 PM
12' Philco
If it is 12', either Kareem or Andre would have to jump pretty high to look at the front panel. Kareem would have an e...morzh — 01:48 PM
12' Philco
And here's a story about the tires on the truck. Same "no-stoop" guy must have installed these! Take care a...GarySP — 01:17 PM
Hickok AC51 tube tester
I think they have only shown the secondaries of the transformer. Two of them feed the rectifiers' filaments.morzh — 12:58 PM
IF can wire size and Rubber mounts?
Arran If the wire inside cans is the gauges you mentioned, the sole reason for that would be mechanical, to stiffen t...morzh — 12:56 PM
12' Philco
Rod, Yes, I know, but the Giant Philco is not around anymore either, so I go by whoever was alive fairly recently. H...morzh — 12:54 PM
Hickok AC51 tube tester
Absolutely no one is going to reverse engineer that circuit. Even the iron core is missing.RodB — 10:37 AM
IF can wire size and Rubber mounts?
Thanks to both members for your help regarding wire and tuner mtg supports. regards--Johngeorgetownjohn — 09:33 AM

[-]
Who's Online
There are currently 6106 online users. [Complete List]
» 1 Member(s) | 6105 Guest(s)
Avatar

>