Philco 38-10 Restoration

[omegaman]

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]

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]

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]

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

[marty59]

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]

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

[bandersen]

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]

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

Just Radios is my source

[omegaman]

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]

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]

Originally Posted by Electronic M

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]

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?



Looks like trick-or-treat

[bandersen]

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]

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]

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.