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-   -   Philco 38-10 Restoration (http://www.videokarma.org/showthread.php?t=252626)

omegaman 11-15-2011 07:54 PM

Philco 38-10 Restoration
 
3 Attachment(s)
Got this nice Philco 38-10 radio. In very nice physical condition.

What are the wire connections on the back for RED, BLK, GND?
Does that 5Y4G rectifier tube look okay?

The radio shows evidence of previous service in 1947. The filter caps look replaced. There are some mods under the chassis and one control seems to be a replacement

I will clean the complete unit of dust and grime
De-Oxit the controls
QD Electronic non-residual cleaner for the tuner vanes
3 prong power cord tied to chassis ground

All major capacitors replaced
New lamp GE-51
Check all resistors for out of tolerance

Any special advice for this radio, like the rubber mounts or anything else that would be helpful

Reece 11-16-2011 05:36 AM

Red is for a regular long wire antenna. Red and Black would be used for a doublet. Ground is Ground. Don't know what you might need in grommets but this outfit sells repro rubber radio mounts of all types including Philco:

http://www.renovatedradios.com/parts.html

bandersen 11-16-2011 01:09 PM

One of my all time favorite radios :)

I suppose the 5Y4 does "look" OK, but you'll need to test it to be sure.

Yes, Renovated Radios does have reproductions of all the rubber bits in this particular set.

Philco 38-XX Dial Assembly Bumper (PHB-38-10)

Philco Chassis Corner Mounts (PHS-COR)

Philco Tuning Cap Support for 38-XX (PHS-38-10)
(note: you'll need to unsolder and pull the tuning cap out to replace these. It's a little tricky, but it's worth it if your existing mounts are rock hard.)

omegaman 11-18-2011 01:15 PM

Underside
 
1 Attachment(s)
Here is a photoshop doc with all the capacitors pointed out

Pretty clean under there.

That bakelite dual .015 MFD capacitor (47) didn't last and was replaced by two .001 caps in series. I don't see how that makes up for the .015 MFD

I ordered the caps $7.07

http://videokarma.org/attachment.php...1&d=1321671345

marty59 11-18-2011 02:05 PM

Not sure what all you know about radios and these old Philco's, but you can rebuild the bakelite sections with new caps quite easily. Once removed, you can chip out the old tar like substance to access the caps inside. Do note how they are connected to the terminals. I'll take some paint thinner and clean out the residue and mount new caps in their place.

omegaman 11-18-2011 02:21 PM

1 Attachment(s)
Someone already bypassed the bakelite multi-cap with the 4x .001 600v sprague tubular caps. The spec calls out for twin 0.015 400v caps so I will replace with twin .015 630v poly caps

http://videokarma.org/attachment.php...1&d=1321647633

bandersen 11-18-2011 02:51 PM

Those caps are right on the AC line to ground so you should use type 'Y' safety caps. More info here: http://www.justradios.com/safetytips.html

omegaman 11-18-2011 04:41 PM

Good point! I added two .015 MFD 275v Y2 safety caps to my order. Thanks

Just Radios is my source

omegaman 11-18-2011 09:24 PM

Now that I am studying the build vs the schematic, I have a question

Refer to the image showing the 4 Sprague caps used to replace the bakelite multi cap part #47

As I understand it, running two .001 mfd capacitors in series reduces the capacitance by half.

That would equal .0005 mfd, which is not the schematic .015 MFD for part 47

Why would the tech use serial .001 MFD caps in this application? (Besides "Thats all he had"

Schematic calls for .015 and all I can get is 275v .015 Y2 safety caps so that is what goes in that position for part 47

Electronic M 11-18-2011 10:29 PM

Maybe they lived close to a station or some source of line noise and he chose those caps to kill some speciffic powerfull interfereing line frequency......though it is just a theory and unless the tech who did that is still alive and kicking to tell us "the world may never know"(as the vintage commercials for totsie pops still say).

omegaman 11-18-2011 10:42 PM

Quote:

Originally Posted by Electronic M (Post 3018802)
Maybe they lived close to a station or some source of line noise and he chose those caps to kill some speciffic powerfull interfereing line frequency......though it is just a theory and unless the tech who did that is still alive and kicking to tell us "the world may never know"(as the vintage commercials for totsie pops still say).

I can definitely believe that analog repair meant get it working here and now

I have to go with the schematics and original design

omegaman 11-29-2011 07:14 PM

All capacitors replaced with pics
 
2 Attachment(s)
I got the new capacitors and did the install.

I checked all the resistors

Y2 Safety caps installed

Left the old replacement "cans" in place just snipped them flush

I'll just sleep on it and fire it up tomorrow

New hard to find $5.00 lamp (GE-51)

Can someone please tell me what control does what?
http://videokarma.org/attachment.php...4&d=1321671348
http://videokarma.org/attachment.php...1&d=1322615543

Looks like trick-or-treat

http://videokarma.org/attachment.php...1&d=1322615543

bandersen 11-29-2011 07:34 PM

Assuming you are facing the radio:
Left control - Power and tone
Center control - Band switch between Broadcast and Shortwave
Right control - Volume

Here are some photos I took when I restored mine: http://www.flickr.com/photos/7003980...644064/detail/

Good luck!

omegaman 11-29-2011 07:41 PM

Thanks,

I couldn't wait

I brought it up and it works great

Nice and loud with a clear tuning across the AM band

No hum and all the controls responded to treatment

The high tone is kinda tinny, the low tone is nice

This was a radio that was put away working and so the restore was easy

What antenna would I set up for SW?

Reece 11-29-2011 08:04 PM

Antenna for both AM and SW: just a wire on the "red" terminal. Should be able to pick up plenty with 20 feet in the house. Better with a long wire outdoors, high as you can get it. Mine is 60 ft. long 30 ft high but whatever you can get outdoors will work. Back in "radio days" people put poles at each end of the roof gables and strung the antenna between, or strung one from the chimney out to a tree or to the garage roof, or just along under the eaves of the house. Most of that is gone now but when I was a kid there were still plenty of remnants of antennas from the thirties and forties. Wire up in the air however you can do it works. However, short wave ain't what it used to be. Most of the good European stations you could get every night have disappeared.

FrankieKat 02-17-2012 01:40 PM

Quote:

Originally Posted by bandersen (Post 3019705)
Here are some photos I took when I restored mine: http://www.flickr.com/photos/7003980...644064/detail/

Nice pics!

I saw the slide where you rebuilt the vernier drive for the tuner and got it "smooth as silk". I'm working on a Philco 37-630 and I've disassembled mine many times and have de-greased it to the point surgically clean, but no matter what I do it still turns very jerky and has a grinding. It's less noticeable on the fine tune, but the outer shaft has a lot of resistance. I've tried WD-40, machine oil and lithium grease and the performance is all about the same. What kind of grease did you use?

If I put the course tuning shaft into the stationary base piece, it turns like silk -- likewise if I place the fine tuning shaft in the course tuning shaft without the bearings it also turns like silk. It's only when I assemble it with the bearings that it becomes rough.

I actually picked up another one from someone and cleaned that up as well, but the same exact problem! On both of them there is a fairly pronounced groove in the stationary piece where the bearings ride inside the inner ring. Wonder if it's possible that is what is causing the roughness? It's tempting to try to smooth out the inner surface with a dremel and very fine polishing tip, but I'm concerned I'd just end up with it no longer perfectly round and make it worse.

I've swapped around the balls and it's also pretty much the same... doubt I have 6 bearings that are misshapen? Same with the tip on the fine tuning shaft -- both of them seem to be round.

Anyone fought with these before? Or am I just using the wrong grease?

bandersen 02-17-2012 04:34 PM

I'm sorry to hear you're having troubles. It's been a while since I worked on this set, but I think I used white lithium grease. Is there anything that provides pressure on the bearings like a spring ?

Reece 02-18-2012 07:05 AM

A slight cleanup of the shaft with very fine wet/dry paper may smooth out the roughness. If you can find the right size ball bearings it wouldn't hurt to replace them. They may be damaged from running dry and oxidizing over the years.


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