Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

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

New Member - Newbie question
#16

This sounds like what I've been going through on a 42-1008. The highest value resistor from the HV secondary center tap to ground smokes and opens.

Check the voltages on your rectifier plates to to ground. Please, be VERY careful-- this thing can bite you hard. They should both be roughly the same (~350VAC). If one is really high and the other one is around zero, you have a transformer winding shorted to ground on the HV secondary. That will smoke that resistor in a jiffy. If this is the case, one of the yellow wires coming out of the transformer probably has some bad insulation and is touching the transformer shell somewhere.

It's not how bad you mess up, it's how well you can recover.
#17

Say again:

Replace each and every electrolytic and wax capacitor before carefully powering up slowly with a variac or dim bulb tester.
#18

Quote:Posted by codefox1 - 01-26-2013 11:26 PM
Say again:

Replace each and every electrolytic and wax capacitor before carefully powering up slowly with a variac or dim bulb tester.

Okay, Im going to build a dim bulb tester and start recapping.
Im slightly concerned that ill get heavily invested into this and then not be able to fix the issues to get it working again, but so far the help ive received here is making me feel a bit better about this.

Thanks for all the help so far. will report back once we get to phase 2.
#19

Okay next problem everyone, (newb question)

I'm going through the capacitor list and getting ready to place an order online when I came across a capacitor that I was unsure of. It's listed on the schematic as #81 dual .01-.01 mfd. Below is an image of the schematic and an image of the outline of # 81. It looks like a black plastic terminal strip and is actually visible in the image that Ron posted previously. My question is, is this thing a capacitor or are there capacitors inside of it? How do I replace these two .01mfd capacitors??

[Image: http://i835.photobucket.com/albums/zz278...09b0dd.jpg]

[Image: http://i835.photobucket.com/albums/zz278...568411.jpg]
#20

Yes, there are two .01 uF capacitors inside the bakelite housing. Quite common in many Philco radios of that vintage. You're about to embark on another great adventure in radio restoration. It's actually not hard to do.

And since those two caps are across the power line, you should replace them with "safety capacitors" while your are at it.

Chuck's excellent site tells how to do it: http://www.philcorepairbench.com/capbuild.htm

Safety capacitors are discussed here : http://www.justradios.com/safetytips.html
#21

Brilliant. Thank you so much for the help and pointing me in the right direction.
I'm hoping to get all the caps I need and get this done in the next few weeks.
Hopefully the next time you hear from me I'll have a fully functioning radio and record player
that I can post pictures of.
#22

Hi all, Me again.

I've been replacing all the caps and came across a problem with the electrolytic capacitors that I'm hoping someone will help me out with. It's obvious that there has been a repair and replacement made in the past as two of the wires leading from the capacitor can have been cut and a large cardboard capacitor added to the underside of the chassis. I'm not sure where to begin to describe the issue I have but maybe just a simple answer about what I should be seeing based on the schematic will clear things up for me.

[Image: http://i835.photobucket.com/albums/zz278...2b1ac2.jpg]

Cap 21B appears to be the one that was replaced. This large cardboard cap has a wire coming out of it that leads to a terminal which is mated to the speaker field coil (76) while the other wire exiting the cap leads to the terminal between the two large resistors on my new Candohm resistor. Cap 21a Looks to still be inside the original can, it has a red wire that comes out of the can and goes to the field coil (and a bunch of resistors) but there is no wire that comes out of the can that leads to my candohm resistor between the 28 and 26 ohm section. Since there was only two wires cut from the original capacitor can which I'm thinking was for 21B, was there never a wire that went to the candohm? The green wire and Black wire seem to be going to the proper places, I'm just not sure what I'm supposed to be seeing here.

Also, based on the schematic above of the Electrolytic capacitor does the little black box represent the positive side?
I guess I was also confused because I always thought the negative side just went to a ground on the chassis.

Any help would be greatly appreciated.

EDIT-- Wait a minute, I think I just figured something out here when reviewing my post, is the Candohm resistor considered a ground because the last 26ohm resistor is connected to a ground? - I told you I was new to this right!?!
#23

Yes the small black box represents the positive side of the electrolytic caps. There was an earlier thread on this topic that might help, see: http://philcoradio.com/phorum/showthread...80#pid4580 and http://philcoradio.com/phorum/showthread...ght=41-608 .
#24

Thank you again!




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Need Help to ID this radio 11 tube Philco
Welcome, the radio looks intimating 11 tubes, wish you well.Jimradio — 07:49 AM
462ron
Hi Dan, it’s been 10 years since I restored the electronics on my 37-116 so I’m going on some foggy memories. I remember...462ron — 07:37 AM
Need Help to ID this radio 11 tube Philco
Yes the 16B as morzh pointed out. Specifically its the January 1935 model version of the 16B. There are a couple earli...klondike98 — 11:51 PM
48-482 rear panel help
Welcome to the Phorum, keithchip! How far you take a radio on cabinet restoration is a matter of personal preference. ...GarySP — 11:28 PM
48-482 rear panel help
I've recently finished the internal restoration of a locally purchased Philco 48-482. The cabinet is in ok shape except ...keithchip — 10:28 PM
Need Help to ID this radio 11 tube Philco
Welcome to the Phorum, Ken! Lots of help here for all of your restoration questions. Take care and BE HEALTHY! - Gar...GarySP — 07:59 PM
Need Help to ID this radio 11 tube Philco
Thank you. I went to your online library and found 2 schematics. I will download and compare to components!Ken D. — 06:31 PM
Need Help to ID this radio 11 tube Philco
It is a 16B tombstone.morzh — 06:13 PM
Zenith H725
David - sorry, I reread your post and finally saw THD - now the % figures make sense. Thanks for explaining. The PSU...EdHolland — 06:06 PM
Need Help to ID this radio 11 tube Philco
Hi Everyone, New member but have been reading this for awhile for tips! Vaccum tubes were before my time so bear with ...Ken D. — 06:03 PM

[-]
Who's Online
There are currently 312 online users. [Complete List]
» 2 Member(s) | 310 Guest(s)
AvatarAvatar

>