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Philco 40-185 - Help Needed
#1

I acquired a philco 40-185 recently in original condition.  The previous owner said he plugged it in and the light came on but it hummed.  I brought it home and took the chassis out.  (This is my second restoration.)  

nyway, I replaced all the old paper caps and the two electrolytics (and a few resistors that tested badly).   I added a fast blow inline fuse.  I replaced the AC line with a modern cord.  I rebuilt the bakelite block with two .01 mfd safety caps.

I have it all put back together and tested it with a dim bulb tester, but no dial lamp and no light at all on the “dim bulb”.  I can confirm there is 120v coming in the main (hot) line which enters the chassis, goes across the fuse then to the bakelite block, then to the on-off switch and back to the AC transformer.  There is 120v all the way to the transformer line on the on-off switch.  The neutral goes directly to a bakelite block.  No tubes are glowing.  No dial light.

Now, I’m stuck.  What should I look for next to determine the problem?
#2

Hi And Welcome,
Would measure the resistance across the primary of the power transformer. Should see a low resistance.

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
#3

Test the transformer primaries for an open...
#4

got 10.1 Ohms across the two primary wires
#5

Thanks for your help!  Your replies helped me locate the problem.  I had one side of the primary connected on the wrong terminal of the bakelite block.  Working very well now!
#6

Hi Doc,
Glad you figured the connections out. I have done about 3 of the 40-185 radios. But as with any resto job you do, it pays to make several photos of the chassis wiring before you start. I still do, and has saved me many times.

 I know we all have our methods of recapping, and of course the paper caps need to be replaced along with the electrolytics.  i personally do all the basic tests first, field coil, transformer with tubes pulled, visual inspection, tube tests. Then I replace the filter caps first, as they are most critical. Then I do a very brief 35-45 second powerup, having the radio pre tuned to a local station. As soon as I hear a station I will power down.  If no stations, but no hum then I will continue to replace a couple paper caps at a time, test again.   The reason is that if you have a working set, and suddenly after a couple caps it is dead, you know right where to look for the trouble. If you replace 15-25 caps all at once and it's dead, you have a harder time to figure out where you may have made a mistake.
Good luck to you and your new hobby!! Gary.




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