advice needed: restoring 47-1230 - FM & AM now works!!!! :D (uncertain about SW)
Posts: 336
Threads: 13
Joined: Apr 2011
City: Montreal, Qc
Greetings,
I am new to antique radios and vacuum tube electronics, sorry if I ask what seems like dumb questions.
I recently got a philco 47-1230 and started to try and get documentation & knowledge on that model. That's how I found here, a goldmine of philco information!
The unit I got was sold in an antique store as "non-working."
Turns out a bit of TLC was all that was needed to listend to Hockey on AM tonight...
When I powered it the first time, all I could hear was a buzzing humming sound. The lamps all lighted up, so I tought I was pretty much set for a working chassis that needed only proper attention.
The knobs are all erased by age and I needed google to help me figure out what was where on the 4 of them - plus the phono-radio pushbutton. Once I placed it properly on BC with appropriate volume, I could hear radio (and hasard made that it was on the station I wanted to find.)
That's about as far as the success goes. The vacuum tubes are all good, the AM wave works fine, I can set some of the pushbutton stations but not all and not on all frequency (if I get about 10 AM stations here on BC, I only get 2 or 3 different ones trying to set the PB, and I can only hear something on 4 out of 5 presets buttons)
Maybe I am not changing the presets properly?
I do not get anything on the FM band. Nothing at all. I found some 47-1230 documents on Nostalgia Air (thanks to the threads on this forums) and they document that an antenna might be required for good FM reception, but we're not talking "bad reception" rather than no reception at all. I guess there's something not OK on the FM side... I am wondering what. If anyone has clues, I'm all ears.
The lights for the front dial were both blown. I tried with a LED replacement and both sockets are OK, just the incandescent lights are burnt. That's an easy fix.
Next is the phono... if I place the phono-radio PB to phono, I hear a humming sound. It intensifies when I touch the phono. But the motor does not turn at all. And there's no cartdriges to read a record so I have no clue if it works at all. I hope to be able to bring that turntable back to life.
I noticed 2 cut wires from the chassis, the pair coming out on the right-hand-side:
[Image: http://i146.photobucket.com/albums/r253/...0_8969.jpg]
see in this picture they go out under the 1230 part number. What are those for? Could they be the cause of non-working phono? I still haven't found anything about that, but haven't got my hand on actual schematics either.
The cabinet is in good shape, considering its age. I would like to bring it back to better condition, but I have no knowledge of woodworking. I think from reading around that we can wax the outter shell?
[Image: http://i146.photobucket.com/albums/r253/...0_8967.jpg]
How should I treat it? sand & complete refinish? or some shining and conditionning? Either way, I am uncertain how to proceed.
I wanted to take more pictures, but had no idea what would be of interest - and the camera's batteries are dead. If there's any particularly interesting pictures to be taken, please let me know and I'll post them.
-Mars
(This post was last modified: 07-05-2012, 09:33 PM by Marsupial.)
Posts: 336
Threads: 13
Joined: Apr 2011
City: Montreal, Qc
I am currently trying to figure out why the phono won't work.
Short of splicing the wires to ensure the power goes all the way to the turntable, how do I check? The small transformer and motor both runs hot, the motor won't turn. I tried to turn it by hand, the mecanism doesn't seem stuck at all.
On the other end, the cable that goes out the arm into what seems like a transformer (I guess its a filter of some sort) into a connector - this is the audio input for the phono into the radio chassis, if I touch it or the frame of the phono, the buzzing sound change. I tried to ground it to chassis, the buzzing sound stops. I am thinking the record changer is no longer properly grounded.
[Image: http://i146.photobucket.com/albums/r253/...0_8971.jpg]
I know the audio from the phono works, I tried to connect something else trough that RCA-style connector and could hear perfectly. All that's needed is to make the disc turn, and to find a cartdrige to pick up the signal.
Am I loosing my time trying to make it turn, being that the cartdrige is near impossible to find?
I am thinking of replacing the phono section completely...
-Mars
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Wow, lots of questions! Welcome aboard, by the way...
As I have heard others say, "the only dumb question is the one that isn't asked."
Your "buzzing or humming" sound is surely due to bad electrolytics. All of the paper and electrolytic capacitors are going to have to be replaced. Read here for more on this subject:
https://philcoradio.com/library/index.ph...urn-it-on/
http://www.antiqueradios.org/powerup.htm
Your not hearing anything on FM is, again, probably bad capacitors. Although a failed tube is not out of the question, you may be surprised to know that most of the tubes in an old radio are usually still good.
You may want to read this thread on another 47-1230:
https://philcoradio.com/library/index.ph...m-philcos/
I don't own a 47-1230, so can't comment on the cut wires.
The preset button switches are probably dirty. DeoxIT is your friend here.
Your cabinet looks like it has been stripped at some time in the past. Sanding is not the answer. You could easily sand through the veneer. There are proper procedures to follow when refinishing a radio cabinet; I would have to defer to the guys here who are much more knowledgeable than I when it comes to refinishing. Steve Davis, Gary Rabbitt, etech, and others whom I cannot think of right now (apologies if I left your name out, folks). Send them a PM if they don't chime in here; they are very helpful fellows as well as being quite knowledgeable.
What seems like a transformer that the audio cable from the record changer connects to, is a transformer. An impedance matching transformer, to be exact.
The original changer may very well be repairable. As for the cartridge, a magnetic cartridge with a 78 rpm stylus could be used in place of the original "Dynamic" cartridge. The 47-1230 has a phono preamp built into the chassis, so this is an ideal setup for a magnetic cartridge.
--
Ron Ramirez
Ferdinand IN
Posts: 190
Threads: 8
Joined: Oct 2005
City: Lexington, SC
Been a long time since I've restored one of these. Got the radio restored not the phono. Seem to remember the rubber parts had petrified over time.
The cut pair of wires in the first posting I'm thinking may have been for the phono lamp for illumination of the turntable. Operates from a limit switch on the front door.
The small transformer is for impedance matching the cartridge to the radio works. Cartridges are always bad after 60 years.
Correction: its a magnetic type, hence the impedance transformer.
Think the turntable motor is a shaded pole induction motor and normally works as long as it gets 110 VAC. I'm surprised it is running hot and not turning. Leads me to believe the motor winding has shorted turn.
Not sure which transformer mentioned is getting hot.
Recapping the radio will likely be needed sooner or later. Was not easy especially those electrolytic cans since the chassis underneath is cramped.
Richard
Posts: 336
Threads: 13
Joined: Apr 2011
City: Montreal, Qc
Thanks for the hints guys!
Light power is a likely candidate for the cut wires: there is an unwired lamp for the phono, and matching wires to a limit switch. I did measure it yesterday, it was a steady voltage, around 6V if memory serve...
- ok, just tried with a light, it works. don't know why someone would cut that, but if the phono had been dead for a while, maybe it was in the way... -
For FM... how does one know if a tube is still good?
as far as I know, there's 9 tubes and they all emit a certain quantity of light when listening to radio. Could a tube still emit a certain quantity of light but not be good anymore?
anyway, I'd tend to think about bad capacitors. I guess if I am to replace any, I need to pull the chassis out of the cabinet?
Phono... can these players player play something else than 78 rpm? I was somehow hoping to play 33 rpm vinyls on it...
Are there any caps on the phono side? because if I unplug the audio connector between the changer and the radio chassis, and connect something else, the humming sound is not there, and the audio is crystal clear. The issue needs to be on the phono side.
I was kind of upside-down trying to look under the turntable, so I am uncertain what was there, but I saw what seemed like a motor, and another module that looks like a coil Both ran hot, so I think power gets all the way there, altough I don't hear, feel or see any motion. As I said, I tried to turn the table manually and it wasn't stuck. I guess there's a short. If Richard is right, and the rubber got petrified, would I be able to turn the disc manually?
The "manual / auto" switch is stuck at auto and won't move to manual. Not that it matter until I can have rotation...
Maybe I should get one of the magnetic stylus cartdrige and see if I get sound out of it... where should I look for those?
At this point, I'll wait until I am done making the electronics work before doing the wood refinish (and wait for warmer meteo too.)
It looks good, but I agree it seems like it had been stripped somewhen. I am under the impression that some cleaning and scealant might be all that's needed.
Thanks again for the welcome and the tips and hints! This is my first vintage radio, I am enjoying fixing it, so thanks for the help!
-Mars
Posts: 336
Threads: 13
Joined: Apr 2011
City: Montreal, Qc
I started cleaning the guts of the chassis...
from that
[Image: http://i146.photobucket.com/albums/r253/...0_9231.jpg]
to that
[Image: http://i146.photobucket.com/albums/r253/...0_9235.jpg]
using q-tips, alcool, and a vacuum cleaner.
Once I was there, I decided to rewire 2 bare wires because they were making me nervous... Some are really not well placed, considering you can't really put the chassis upside-down.
Next step will happen when I have my electrolytic caps - hopefully soon.
-Mars
Posts: 336
Threads: 13
Joined: Apr 2011
City: Montreal, Qc
My main question of the day:
The PB/BC/SW/FM rotary switch is giving me issues. I need to push it in for the signal to work, otherwise I loose signal. At least, that's how it behaved on AM today when I tested it after changing wires. I almost tought for a while I soldered one wrong!
Is that something we clean, or something that we change (if so, where to find a suitable replacement???)
-Mars
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Clean it, using DeoxIT. This should make your switch work properly.
Don't use the cheap contact cleaners, which may or may not work. If DeoxIT doesn't clean that switch, nothing will.
Spray the contacts with DeoxIT, then turn the switch back and forth several times to allow the DeoxIT to work into the contacts well. Then, let the residue evaporate before you apply power again. DeoxIT evaporates more slowly than some contact cleaners, so allow plenty of time for that and be patient.
--
Ron Ramirez
Ferdinand IN
Posts: 336
Threads: 13
Joined: Apr 2011
City: Montreal, Qc
Thanks for the tip, Ron.
I am trying to locate a good supplier of deOxit in Canada, and notice there's a lot of different products. Some are spray, some are neddle application, some are brush-on.
Also, there's some 5% deOxit, and some 100%.
I am looking at the mini-aerosole 5% can for its narrow fitting that would make it easier to spray in the pots and switches, but should I be trying to get something else?
-Mars
Posts: 7,248
Threads: 266
Joined: Dec 2009
City: Roslyn Pa
Whole heartedly agree with Ron. I'll point out that you need to be sure that all of the DeOxit is dry before you apply power. I've had a cleaned switch catch fire from arcing and just a bit of cleaner.
Terry
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
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
I use DeoxIT D5 in the aerosol can.
Once I finished rebuilding a 41-226 "Sled," I tried using contact cleaner on the pushbutton mechanism. The pushbuttons still refused to work correctly after cleaning with the generic contact cleaner. So, I sprayed them with DeoxIT D5, and that's all it took...the DeoxIT restored the pushbutton mechanism to proper operation.
Read about the 41-226 here:
https://www.philcoradio.com/phorum/showt...?tid=14923
7estatdef Wrote:I'll point out that you need to be sure that all of the DeOxit is dry before you apply power.
Yup. Allow the DeoxIT to evaporate before applying power = let it dry before applying power = same thing.
--
Ron Ramirez
Ferdinand IN
Posts: 336
Threads: 13
Joined: Apr 2011
City: Montreal, Qc
I can't seem to find DeOxit locally here in Canada. I have a co-worker that says an electronics store near his place might have some, otherwise I'll order, I might have found canadian supplier that would ship to here.
In the meanwhile, I have purchased another contact cleaner, thinking It'll be a start. It does work wonder on the volume pot.
But I realised the PB/BC/SW/FM switch is a beast on its own!
It is not a single casing with 4 contacts, but rather a mecanism, leading to a rod that includes a series of sets of switches.
from that top knob:
[Image: http://i146.photobucket.com/albums/r253/...0_9255.jpg]
to that shaft:
[Image: http://i146.photobucket.com/albums/r253/...0_9257.jpg]
here's one end inside the chassis:
[Image: http://i146.photobucket.com/albums/r253/...0_9260.jpg]
[Image: http://i146.photobucket.com/albums/r253/...0_9263.jpg]
another end of the chassis:
[Image: http://i146.photobucket.com/albums/r253/...0_9266.jpg]
In essence, there's like 4 sets of switches in there. I fail to see why pushing the knob gets better contact under those conditions. I wonder if it might be related to a wire I changed, leading to a lesser quality connection? I'll have to give it a try, after I change my e-caps. After cleaning and letting evaporate for about an hour, the result wasn't as expected and all is still as it was. "better luck next time"
On a better note, I received my caps!
[Image: http://i146.photobucket.com/albums/r253/...0_9274.jpg]
Overtime aside, I might have time to do that before easter.
So I have 22mF 450V as a replacement for the 20mF & 25mF e-caps.
-Mars
Posts: 336
Threads: 13
Joined: Apr 2011
City: Montreal, Qc
I decided to wait till I get the proper lug strips before soldering the electrolytics.
well, today I got my hand on those, from a friend who repairs vintage pinball, NOW lug strip of the same model as in the radio
[Image: http://i146.photobucket.com/albums/r253/...0_9319.jpg]
guess I'll be soldering soon
-Mars
Posts: 336
Threads: 13
Joined: Apr 2011
City: Montreal, Qc
Installed a new lug strip, rewired the connections for the cans to 3 brand new 22uF ecaps.
now I don't have AM anymore.
what do I do?
-Mars
Posts: 336
Threads: 13
Joined: Apr 2011
City: Montreal, Qc
the Phono switch still amplifies the hum from the phono, leading me to believe the power stage (section 1) is correctly wired, and the amplification stage still works.
However, no more AM is being received.
Is it possible a component non-related to the redone wiring has failed?
I double-checked the connections prior to applying power, and tripled checked once I didn't get AM. The soldering seems OK with continuity test, the capacitors polarity is good and all the components are as they were prior to the change (minus the change of e-Caps) I used 450V 22uF for C102A, C102B, C103.
I don't think there's anything wrong with the new caps, what could I have made bad?
-Mars
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