The PHILCO Phorum
37-675 - Printable Version

+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Philco Radio Discussions (https://philcoradio.com/phorum/forumdisplay.php?fid=5)
+--- Forum: Philco Electronic Restoration (https://philcoradio.com/phorum/forumdisplay.php?fid=8)
+--- Thread: 37-675 (/showthread.php?tid=6774)

Pages: 1 2

37-675 - murf - 05-31-2013

Well guy's, I brought another one home.
As if I have room. Couldn't resist.
Got a really nice virgin 37-675 from a person that was moving and did not have room.
THing has not been plugged in for years.
Cabinet was professionally re-finished years ago. Lots of different veneers in this one.
Must have been the last of the legged models.
Has 12 tubes.
Brought it home and checked the chassis out for obvious problems, and plugged it in to my variac.
After a few minutes of cranking the variac up, I got audio and faint signal.
Very promising.
Only problem I see right away is that the tuning condensor is not turning with the control knob.
Looks like there is a loose or disengaged gear on the front of the shaft.
Anyone have a good diagram of how the tuning mechanism is supposed to work on this model?
I think I will re-cap,check resistors and tubes and see what happens.
Not a bad find for $25.00.
Input or suggestions?
murf

RE: 37-675 - morzh - 05-31-2013

I suspect the tuning mechanism is the same as in 37-116. The gear itself will not slip, but there is the coupling that connects the output shaft of that whole concoction with the shaft of the cap. The cap is held by two set screws of that coupling and so is the shaft of the gear. Pretty straightforward, you just have to look what is slipping. You will have to pull out the chassis, but have to do that anyway.

Good luck and congrats, for 25 bucks this is a gift.

RE: 37-675 - Radioroslyn - 06-01-2013

Have seen that coupler fall apart too.
Terry
Great deal for $25!!!

RE: 37-675 - murf - 06-01-2013

Have not taken it apart yet, but it looks like there are a couple gears towards the front of the shaft that are slipping on the shaft.
Wonder if they are stripped? Looks like a serrated shaft.
Probably see if I can fix that before I dig into the rest.
Anyone know where I can get parts for the tuning mechanism if I need them?
THanks for the replies guy's.
murf

RE: 37-675 - morzh - 06-01-2013

You can try to use some special epoxy to secure the cogwheels. And the lubricate it well with lithium grease to keep the torque acceptable.

RE: 37-675 - murf - 06-01-2013

Looks like the front portion of the shaft has the splines wor out as well as the 2 small gears that engage it.
WHy do they use 2 gears back to back on this mechanism?
I think I will need to look for the front end assembly with the gears and the shaft to the point where it attaches to the rubber disc. Maybe even farther up the shaft to where it connects to the tuner assembly?
Anybody know what models use this configuration?
Maybe someone has a junk chassis laying around that I could steal parts off of?
Have to put it aside for a while and see if I can find parts.
I am supposed to pick up a 38-3xx nest week that I plan on using for salvage, depending on how it looks when I get it home.
Any similarities between the 2 chassis tuner mechanism's?
murf

RE: 37-675 - TA Forbes - 06-01-2013

That's a great find!!!!

Icon_thumbupIcon_thumbup Icon_wave

RE: 37-675 - Radioroslyn - 06-02-2013

WHy do they use 2 gears back to back on this mechanism?

It's called an anti-backlash gear. There is also a small spring between the two gears. It puts tension between the two sets of teeth so that there isn't any play between it and the gear it's mated to. If you've take it apart be sure to add a little to the two gear before assembly.
Terry

RE: 37-675 - murf - 06-02-2013

Thanks Terry,
Unfortunately the springs are missing on the 2 gears.
Might have to try to find another similar mechanism and steel some parts.
HAve a great day.
murf

RE: 37-675 - Ron Ramirez - 06-02-2013

murf Wrote:Anyone know where I can get parts for the tuning mechanism if I need them?

The following Philcos all use the same basic assembly:

37-9
37-10
37-11
37-675 De Luxe
37-116 De Luxe
37-690
38-1
38-2
38-3
38-116
38-690

Note that the 1938 models only use 2 lamps to light up the preset tabs while the 1937 models use 4, but the mechanisms are otherwise identical.

RE: 37-675 - Radioroslyn - 06-02-2013

You mean 37-116 code 122. This Deluxe is a little confusing.
Terry

RE: 37-675 - murf - 06-02-2013

Hi guy's,
Getting alot of useful info here.
Mine is not the deluxe model, so it does not have the tuning dial with the presets. Just the standard Philco round dial .
Looks like there were about 3 versions of the 37-675 model.
Would be nice to find the front tuner assembly from one of the models Ron mentioned.Looks like there were many with the same assembly.
Then I wouldn't have to steel one off another that might be better left whole.
murf

RE: 37-675 - Art Hoch - 06-05-2013

Note that the 1938 models only use 2 lamps to light up the preset tabs while the 1937 models use 4, but the mechanisms are otherwise identical.

--------------------------------------------------------------------------------
Hey Ron,
The dial lamps on my 38-1 do not light up the preset tabs.
Art

RE: 37-675 - Ron Ramirez - 06-05-2013

The Magnetic Tuning Off-On switch has a habit of going bad, where it will turn the AFC circuitry (Magnetic Tuning) off and on, but will not turn the lamps off and on. If cleaning does not help, a new switch is the only cure.

RE: 37-675 - murf - 06-05-2013

Well, thought I had the parts to replace mine, but alas, upon looking close at it the 38-3xx has a different assembly due to the station preset buttons.
Guess I will have to see if I can fix my original by gluing the gears on.
Guess the antibacklash springs would not do me any good either.
Did hook the 38-3xx up to my variac and I did get some activity as far as tubes etc., but no real reception.
Might have to just put it in the to do pile that is getting too big.
murf