Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

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

40-180 electrical troubleshooting
#1

I’m currently working on my Philco 40-180 radio. I’m having an issue. No sound. Low hum from speaker. I keep smoking (60) resistor. My voltage across the (61) capacitor is 200VDC and the voltage across (58) capacitor is around 40VDC. Not sure what’s going on. I appreciate all the help this is my first radio and I only have a basic knowledge of electronics. Thank you


Attached Files Image(s)
   
#2

Greetings;
I would suggest checking for voltage on the plates of the audio output tubes, the output transformers in these sets are notorious for failing primary windings. It is also possible that you may have a shorted tone correction capacitor connected across that same audio output transformer, or possibly a very leaky bypass capacitor elsewhere loading down the plate voltage.
Regards
Arran
#3

You have a bad, bad tube or a short somewhere.
You should not just turn things on. Check for low resistance across 58, make sure it is not the 58 itself, and start looking for the bad part.
PS. Having started the thread, it makes sense mentioning if the recap has been done, tubes checked, etc.
We cannot say much until we know the basics.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#4

I replaced both 58 and 61 on the schematic. I noticed when I unplugged the speaker itself the resistor (60) 150om does not get hot. I went through and replaced any broken wires and any resistors that look bad or tested off. Not to sure I appreciate all the help I’m still new to this and only have a basic knowledge of any electrical work. Thanks again
#5

That's what we strive for here. First-timers to electronics gurus reside here. We just want to see an era maintained and remembered. Ask questions all you want. You can almost bet someone else dealt with a similar issue. Lots of help available. Take care and BE HEALTHY! Gary

"Don't pity the dead, pity the living, above all, those living without love."
Professor Albus Dumbledore
Gary - Westland Michigan
#6

I isolated the circuit. And I’m still blowing 60 resistor. I just ordered the 84 rectifier tube. To see if that’s the issue. I already replaced both (58 and 62) capacitors. All the resistors are all replaced in this section of the circuit. How can you test the field coil and the transformer? If I take the 2 resistors off (59 and 60 My voltage is around 360vdc. I appreciate all the help thank




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
B&K 1077B no video
Hello Tim, I would if it's a leaky Capacitor So are all 3 of those B- voltages low then ? Sincerely Richardradiorich — 01:55 AM
B&K 1077B no video
I found a schematic and think I have the problem traced down to the minus power supply. I have very low voltages that go...TV MAN — 12:41 AM
RCA 15X
I'd try replacing the bulb first and if that doesn't do it, then change the 35Z5 and see if the problem goes away.NostalgiaRadioTime — 12:28 AM
B&K 1077B no video
Hello Tim, I have that exact unit in my shop too plus a Sencore unit there are times I like one or other !!. Sincerely...radiorich — 11:07 PM
RCA 15X
Everthing goes at once, maybe it's the cold weather, I have had 2 dial strings break and no my little RCA is having dial...Paul Philco322 — 10:26 PM
Philco 91 Schematic
Hi Dan, I can't explain this specific resistor but I have seen the use of a switch to apply B+ voltage to screen gri...RodB — 09:36 PM
6TPZ and 5TPO Radio Help
I suspect it's been repaired before. And I suspect whoever repaired it, wanted to re-use old transistors' pin stubs in o...morzh — 09:24 PM
B&K 1077B no video
Thanks Rich! I'll take a look and see what he has. I know there's more modern equipment to be had, but this one I know a...TV MAN — 09:11 PM
B&K 1077B no video
Hello Tim, Here is a link to restoration of one on Phil's old radios site ! Sincerely Richard bk1077bradiorich — 09:01 PM
6TPZ and 5TPO Radio Help
I'm a little befuddled on this one. Should X5 and X4 be tied together like this?  It looks like someone added this at so...R3Sons — 07:33 PM

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

>