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Philco 37-670 -- No Reception!
#1

Hi Everyone,

I am in the process of restoring a Philco 37-670 console floor model.  So far I have replaced all three filter capacitors, two of the Bakelite blocks (including the one containing the across-the-line caps) and the pilot light and the shadow meter light.  Last week, I powered the radio on for the first time so I could get a baseline on its functioning before continuing with re-capping, etc.

The radio powers on just fine - it runs at about 90 watts on 110 volts and all of the tubes light up.  However, there is no reception of stations whatsoever and the volume is very low.

My question is why this radio is not picking up stations.  According to the instructions on the schematic, "if a temporary aerial is used, the jumper should be across terminals 2 and 3.  The aerial connects to terminal 1 and the ground lead to terminal 3."  So I placed the jumper across terminals 2 and 3 and I attached a long piece of wire onto terminal 1.  I think this should be sufficient to pick up a rather strong AM station located about 2 air miles from me - that station is so strong I can pick it up on even the most deaf radios.  Other tube radios in my collection have received this station even without an antenna attached.   But the Philco won't even receive this station.

Any ideas as to why it's not receiving anything?  Unfortunately, I don't have a tube tester so I don't know how good the RF tubes are in this set, but they do at least light up.  The set did come with some kind of antenna attached to the cabinet - it's kind of compact and inside a metal case.  I can't quite figure out how that antenna is supposed to work.  But right now, the cabinet is being restored by a family member so I don't have ready-access to it.  

Thanks in advance for your help and advice!!!

~Mountaineer
#2

You need the original antenna or one with the same inductance.
#3

Dale This set doesn't have a loop ant in the cabinet. Generally that didn't happen till 1940.

>Any ideas as to why it's not receiving anything?

You need to finish servicing the chassis BEFORE you can expect anything to work. Trying to troubleshoot before the service is a waste of time. If this was 60yrs ago and the set was 10yrs old then it might be different but it isn't.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#4

Do you have an ohmmeter to check the coils?
Forrest.
#5

I agree with Terry and you need to see if you can get the tubes tested. All electrolytic and paper/wax capacitors should be replaced and the value of all resistors checked. Once that is done, then you can begin to troubleshoot. I suggest you start at the output side and work your way back. There are numerous videos and discussions out on the internet that describe the process.

Bill
#6

Yes, don't rush the restore, finish the rest of the servicing by checking all coils for continuity, replacing the paper capacitors, test the resistor values, check voltages at the tube sockets and clean controls and switches. Then check out the audio section operation by touching the grid of the first AF amplifier with a screwdriver. If you don't get a hum with the volume turned up, fix it. Then go on to the RF section. Let us know how you get to this point. Good luck, stay focused. There are a lot of old parts in there!

Rod




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