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

Philco 118 - Power Transformer Shorted?
#1

This set fails the dim bulb test with the rectifier tube removed. Transformer primary measures 2.3 Ohms. I assume the transformer is shorted, correct?
#2

Possibly but not necessarily. Did you remove all the other tubes also? There are lot of them and all the filaments combined will put a significant load on the transformer. 

What wattage bulb are you using? The power transformer is pretty large and can draw appreciable line current.



Do you have a Variac where you can bring the voltage up slowly and see when the AC line current starts to increase?
#3

Unless it is a short in the wiring to the transformer or between its secondary and the rectifier, I would say yes.
Yes it does matter what wattage you are using for a lamp. I assume you know what to use for the lamp.
Rob
#4

It's a 100W bulb and lights brilliant immediately. I measured several of my large transformers and they all measure at least 5 Ohms. Owner reports "smoke and burning electronics" at last turn on. I called him after I posted this thread.
#5

Bad short somewhere.




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
New Philco Repair Bench
I am sure this is the archive, and not the Chuck's site.morzh — 09:50 PM
Made mistake & did not label connection
It's not like we are good friends with that wire and can tell it from other ptetty identical looking wires. Why'n't you...morzh — 09:49 PM
Made mistake & did not label connection
I'm not sure why that wire wasn't covered in the video. I'm pretty sure the 6A8 won't work until that pin is grounded. Y...RodB — 09:47 PM
Made mistake & did not label connection
You'll have to forgive me, I am not sure what you mean.  Can you explain what you are really saying.  If anyone does not...georgetownjohn — 08:05 PM
Made mistake & did not label connection
Those are details better left to the ones who know. Maybe you disconnected the wrong end of the wire.RodB — 06:22 PM
Made mistake & did not label connection
Maybe this is starting to make some sense in my hard head.  Is this why the wire in question was not in the great Ron Ra...georgetownjohn — 04:34 PM
Made mistake & did not label connection
I was correct with the 6A8 pin connection's, 7 and 8 are connected to ground as well as the tube shield (the broken line...RodB — 02:41 PM
Made mistake & did not label connection
What does the dotted line representing that surrounds the tube in the schematic?georgetownjohn — 02:17 PM
Made mistake & did not label connection
Hello John, I have been there either label got lost or was not labeled ! Sincerely Richardradiorich — 02:15 PM
Made mistake & did not label connection
Sorry, it is a Philco 37-640.  Does that help?--Johngeorgetownjohn — 02:14 PM

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

>