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Philco 37-62 Rectifier question - Printable Version

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Philco 37-62 Rectifier question - Shaleradio - 11-05-2017

[attachment=14686][attachment=14686][attachment=14687][attachment=14686]My current project is a Philco 37-62 which I acquired to hopefully repair.  Before recapping, I tried to turn it on using a voltage limiter with a 60 watt bulb and got nothing.  I then attempted to test continuity in the transformer.  The primary winding was good.  Next I attempted to check the plate and filament connections on the Rectifier Tube.  Here is where I could use your advise!
Schematics show a 5Y4-G.  The Tube is actually a 5Y4-GT
The resin base is broken (see pix)
If I follow the key on the base ( if the Tube is in correctly, as the resin keyway has dislodged) I get continuity on 7 and 8 which should be the filaments, but as you can see from the pictures, there are no solder joints on 8. 
I also get continuity readings on 3 and 5 (according to the Tube data on the 5Y4GT) but it is from the solder joints behind the pins and there is no pin on 5. (Which would be #4 if you follow and number each pin slot on the resin base, but the data for Tube 5Y4GT seems to call pin 4, pin 5.)
Do you know what direction I should take from here?  
I am new at this and have a multimeter to test with.
If these questions are elementary I apologize, but with your help, maybe I can get this radio back to life.
Thanks!

[attachment=14686]

RE: Philco 37-62 Rectifier question - morzh - 11-05-2017

No your tube is inserted wrong. The two pins on top of the photo are 7&8 filament, the burnt wire is pin 3 plate I and the next one that you thinkmis pin 1, is pin5, plate II.

And, your panel us badly burnt and so is the wire at pin 3, and you should not piwer anything till this all is fixed.

RE: Philco 37-62 Rectifier question - Radioroslyn - 11-05-2017

Would drill out the rivets and replace the octal socket. It's been arcing, and how! Should see HV ac across pins 3 and 5 about 650v. Don't try to measure it with this socket in place. You may have a burned up hv winding.

RE: Philco 37-62 Rectifier question - Shaleradio - 11-06-2017

Yikes! Thanks for your quick response! If the transformer winding is fried, I think it looks grim, but, with the tube inserted wrong and the base broken, if this were your project, what would be your next step? I'd hate to replace the base if the winding has been compromised.
Thanks for all of your help!

RE: Philco 37-62 Rectifier question - morzh - 11-06-2017

Terry has just told you what to do - replace the socket, there is NO saving it. The transformer might still be ok.

BTW it does look the socket has a notch for the key in the right place, you can see it about 2-o'clock, that how I think the tube should be inserted.

I would check the transformer first. I would also disconnect that socket (having taken a good photo first and labeling and insulating the wires) before doing that, plus removed all the tubes.
If it is good:
After replacing the socket - full recap, then the rest.

RE: Philco 37-62 Rectifier question - Radioroslyn - 11-06-2017

Would carefully unsolder the HV winding by heating the joint and unwrapping the wire from the terminal. Try not to flex the  wires as the insulation is fragile. Measuring the resistance from chassis gnd to each of the two affected wires. Should see on one about 392 ohms and 402 on the other. If you come close then I would proceed by keeping the wires apart and away from the chassis. Power up for 5-10 min and if the transformer doesn't get hot, belch smoke or fire your good to go on and replace the socket. Would add a layer or two of shrink tubing over the exsisting wires to provide so insulation. If you need a socket drop me a pm and I'll put one in the mail to you.
 If there is a much higher resistance then you are looking replacing the power transformer which is not too much of a big deal but can be costly of you go w/ a new one.

RE: Philco 37-62 Rectifier question - morzh - 11-06-2017

This lower HV wire needs replacement. Maybe a piece of it could be snipped and then a good wire could be spliced.
heat shrink....only if several layers.

BTW I noticed the chassis itself looks very, very dirty: I never encountered this. Even if a chassis all rusty on top, inside is usually very clean, with a few dead spiders at most.

This one seems covered with some tar.....

RE: Philco 37-62 Rectifier question - Shaleradio - 11-06-2017

Thanks for your help. Morzh, I flipped the tube based on your assumption, and with the tube out, the notch was clear. Once reinserted, the pins made sense...however, pin 3 which was doing all the tailgating is very loose because that section of the tube base was cooked as well. I still get great continuity on the filaments, but nothing on the plate pins. I will desolder and disassemble as Terry suggested to see how cooked the wires are and finally see if my transformer has been toasted. BTW, the "Tar" is discoloration from the arching of the pins just in the area of that Rectifier. Thanks again for all of your input.

RE: Philco 37-62 Rectifier question - Radioroslyn - 11-07-2017

So it sounds like your in the market for a power transformer. I took a quick look and found over on Playthings of the past and found this:
4519-166  POWER     PHILCO 8046       340-0-340V @65MA, 5V 2A, 6.3VCT @2.2A, FIG 1, MOD 60/505,U  1  3 1/4 4 3/8 3 0/0  16.50
Electrically it's a good match but the mounting is a bit different, it mounts on top of the chassis rather than half of it mounting below the chassis. Don't think it will present a major problem to mount. A new Hammond transformer is about $75.

RE: Philco 37-62 Rectifier question - morzh - 11-07-2017

Before buying anything make sure you make contact on the plate pins, as often times the oxidation prevents probes from making the circuit.
Otherwise, yes, you have to get the new tranny.

RE: Philco 37-62 Rectifier question - Shaleradio - 11-07-2017

Thanks all! Amazing help on this site! Thanks Terry for looking for that transformer for me!
Mark

RE: Philco 37-62 Rectifier question - Radioroslyn - 11-07-2017

No problem I was just sitting around doing nothing [Image: http://philcoradio.com/phorum/images/smilies/icon_smile.gif]. Got your parcel off this morning and though in a few extra parts you'll need. If you feel like you need to be doing some thing you could use your ohm meter to measure the carbon resistors to see if they are within 20% tolerance. Didn't see any resistor with a parallel part that would drastically effect the resistance reading.
Have fun!!!