Posts: 62
Threads: 20
Joined: Apr 2015
City: Decatur Alabama
I got a 48-1263 some time back and yesterday I got around to recapping it. Someone had already been there and I only had to replace 4 paper/wax caps and both can caps and one 15K resistor that was reading 27K. Plugged it in and got nothing but dial lights glowing. I checked the tubes and 4 of the 8 showed bad or questionable. Is this likely or is my old Heathkit tester on the fritz? When I picked it up the owner had it turned on with the turntable running to show me "it works". I immediately unplugged it and took it home, but could she have done something then that wrecked those tubes? Yes, I am very new to restoring radios. Help!
Posts: 126
Threads: 13
Joined: Sep 2013
City: Milwaukee, Wisconsin
Bad or weak tubes on a tester don't always translate into non functioning tubes. I would start by doing voltage checks (assuming you have a DMM) on the tube pins to make sure they are within reason of what is provided on the schematic. What other testing tools (sig gen, tracer, etc...) so you have, if any?
Posts: 16,219
Threads: 562
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
There are more to the radio than just tubes. RF coils that can get open, oxidized panels and switches, speaker, transformer.....so, start telling us what you have checked so far.
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.
Posts: 2,353
Threads: 92
Joined: May 2010
City: Clayton, NC
It's also possible that the tester is not reading properly.
Which model Heathkit are you using??
Posts: 2,353
Threads: 92
Joined: May 2010
City: Clayton, NC
Also unclear about the radio as displayed to you in the shop: was it actually receiving radio stations?
Posts: 62
Threads: 20
Joined: Apr 2015
City: Decatur Alabama
(07-13-2015, 01:04 PM)Nick3092 Wrote: Bad or weak tubes on a tester don't always translate into non functioning tubes. I would start by doing voltage checks (assuming you have a DMM) on the tube pins to make sure they are within reason of what is provided on the schematic. What other testing tools (sig gen, tracer, etc...) so you have, if any?
I have a multimeter and an old heathkit signal generator.
Posts: 62
Threads: 20
Joined: Apr 2015
City: Decatur Alabama
(07-13-2015, 01:14 PM)morzh Wrote: There are more to the radio than just tubes. RF coils that can get open, oxidized panels and switches, speaker, transformer.....so, start telling us what you have checked so far.
I haven't checked anything else but tomorrow I am going to buy a magnifying lens so I can read the voltages on the schematic and we'll go from there.
Posts: 62
Threads: 20
Joined: Apr 2015
City: Decatur Alabama
(07-13-2015, 01:41 PM)TA Forbes Wrote: Also unclear about the radio as displayed to you in the shop: was it actually receiving radio stations?
No. I bought it from a private individual who was moving; when I got to her house the radio was the only thing left, and she had the turntable running. I didn't hear any sound out of the speaker. The turntable will run very well right now so am I correct in assuming this means the power transformer is okay?
Posts: 2,353
Threads: 92
Joined: May 2010
City: Clayton, NC
The schematic in nostalgia air is tough to follow, BUT:
1. No, the power to the turntable is house current, switched.
2. If half the tubes are reading ? then that could be the problem.
PM me with what tubes are bad, I may be able to help.
Once you KNOW all tubes are good, then we can start troubleshooting.
If your sig gen has an audio output signal you can use separately or modulate with an RF signal, recommend this:
1. Inject an audio signal on the wiper of the vol control. If you hear it in the speaker and can control the volume by turning the vol control shaft, then trouble probably not in the audio section.
Posts: 62
Threads: 20
Joined: Apr 2015
City: Decatur Alabama
Sorry for the long hiatus...but I want to tell everyone that the tubes WERE bad. New tubes and the 48-1263 is playing like a new radio! Got a new cartridge ordered from Ed Crockett of Vintage Electronics in Hattiesburg so the phonograph will soon be back to life also.
Posts: 5,124
Threads: 271
Joined: Nov 2012
City: Wilsonville
State, Province, Country: OR
Posts: 32
Threads: 0
Joined: Aug 2013
City: Ontario Canada
Glad you got it going.
I've bought a couple of radios, where some unscrupulous seller had put all his old non working tubes in.
Both times it was through -bay. Maybe they were unhappy that the radio didn't sell for more, so they were trying to cut their losses.
Users browsing this thread: 4 Guest(s)
|
Recent Posts
|
6TPZ and 5TPO Radio Help
|
OK, so 18 and 19 as they should be.
What is "everything else?"
Try to be more specific in your descriptions:...morzh — 12:44 PM |
6TPZ and 5TPO Radio Help
|
Yeah, I'm still on 5TPO. Sorry, my bad, points 1 and 2 should be points 18 and 19 (easy mistake :think: ) X7 is shown ...R3Sons — 11:42 AM |
Philco 40-120C Filament Wiring
|
Hi folks, I'm in the process of restoring a Philco 40-120C and I'm finding the wiring to be a bit puzzling. According to...bluecap — 11:28 AM |
462ron
|
Hi Levi, here’s just a thought. Most radios run the oscillator higher than the dial setting. Say you set your radio to 1...462ron — 10:10 AM |
1930s Stewart-Warner Tombstone Radio need help identifying model number
|
Another Update: I found a couple of damaged coils inside this radio that might have something to do with why this radio ...captainclock1988 — 10:51 PM |
6TPZ and 5TPO Radio Help
|
If you are still on 5TPO, you lost me there. What X7? What Points 1 and 2?morzh — 08:37 PM |
6TPZ and 5TPO Radio Help
|
Quick progress report:
X7 is broken. Only one leg soldered, the other missing and the diode is cracked.
I've replaced...R3Sons — 05:05 PM |
6TPZ and 5TPO Radio Help
|
Oh...and you have electrolytic caps there.
All need to go and be replaced.morzh — 04:36 PM |
6TPZ and 5TPO Radio Help
|
Thanks, will do.R3Sons — 01:25 PM |
1930s Stewart-Warner Tombstone Radio need help identifying model number
|
UPDATE: I was able to pick up a signal generator on the cheap (amazingly enough) on feebay and I did an IF alignment fol...captainclock1988 — 09:53 AM |
Who's Online
|
There are currently 6909 online users. [Complete List] » 2 Member(s) | 6907 Guest(s)
|
|
|
![>](https://philcoradio.com/phorum/images/bootbb/asb/right_arrow.png)
|