Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

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.




Users browsing this thread: 3 Guest(s)
[-]
Recent Posts
HiFi (Chifi) tube amp build - but my own design.
Tim, nice write up and thanks for sharing !! Sincerely Richardradiorich — 02:47 AM
HiFi (Chifi) tube amp build - but my own design.
Well, this was a real "Hum-Dinger" :lol: ! This will be kinda long, but hopefully it will help others having t...TV MAN — 01:55 AM
Shadow Meter Bulb
Phorum members, I am trying to find the bulb # for PHILCO Shadow Meter part number 45-2180 that is from a 37-640 chassis...georgetownjohn — 06:53 PM
Philco 41-608 changer coupler
3D-printing...short of machining, of course. Or molding.morzh — 05:20 PM
Philco 41-608 changer coupler
Thanks, Morzh. That solves the issue of the rubber pieces. Now, I need to find a way to replicate the pot metal piec...alangard — 05:07 PM
12' Philco
If it is 12', either Kareem or Andre would have to jump pretty high to look at the front panel. Kareem would have an e...morzh — 01:48 PM
12' Philco
And here's a story about the tires on the truck. Same "no-stoop" guy must have installed these! Take care a...GarySP — 01:17 PM
Hickok AC51 tube tester
I think they have only shown the secondaries of the transformer. Two of them feed the rectifiers' filaments.morzh — 12:58 PM
IF can wire size and Rubber mounts?
Arran If the wire inside cans is the gauges you mentioned, the sole reason for that would be mechanical, to stiffen t...morzh — 12:56 PM
12' Philco
Rod, Yes, I know, but the Giant Philco is not around anymore either, so I go by whoever was alive fairly recently. H...morzh — 12:54 PM

[-]
Who's Online
There are currently no members online.

>