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NA4BH
01-21-2011, 12:53 AM
Which one of you guy's work on old radios? I have become the proud (and I mean that) owner of an old Montgomery Wards "AIRLINE" Am radio, it was my Mothers. It is all original and it works (it does have a lot of crackle). I need some one to go through it and check it out. Check the tubes and other components (replace as needed), with the hopes of helping it last another 60+ years. If you are interested and can do it, let me know.


It is not a DOA that needs resurrection.

w2amr
01-21-2011, 04:58 AM
Which one of you guy's work on old radios? I have become the proud (and I mean that) owner of an old Montgomery Wards "AIRLINE" Am radio, it was my Mothers. It is all original and it works (it does have a lot of crackle). I need some one to go through it and check it out. Check the tubes and other components (replace as needed), with the hopes of helping it last another 60+ years. If you are interested and can do it, let me know.


It is not a DOA that needs resurrection.Do it yourself , it's really not that hard. I can steer you through it.What model is it?

WØTKX
01-21-2011, 05:20 AM
A favorite toy from my childhood, and old tubester AM radio! A lot of them even have the schematic printed on the label. They are easy, but the voltages can be a bit exiting.

George is right, do it yourself with some help... get some pics on here. :agree:

NA4BH
01-21-2011, 09:18 AM
I'll give it a try, but when the Eastern Seaboard is wiped off the map................. :lol:

It is Model 84BR-1503

N8YX
01-21-2011, 11:19 AM
If you need toobs for the thing, get in touch. I have a bunch which were used in assorted old AM / AM-FM BCB rigs.

Yours for shipping.

W5RB
01-21-2011, 11:24 AM
Looks like it was built circa 1945 . Schematics are on the web , for pay , or looks like maybe a freebie at one site , though a free-trial viewer download is needed to view that .

http://www.radioatticarchives.com/images/a/thumbs/Airline_64BR-1503B_Schwartz.jpg

NA4BH
01-21-2011, 02:11 PM
Are there any tricks to repairing an old speaker that has cracks in the paper?

KG4CGC
01-21-2011, 02:13 PM
Are there any tricks to repairing an old speaker that has cracks in the paper?
Depending on how dried out it is, you could get by with a very thin application of rubber cement.

W5RB
01-21-2011, 02:16 PM
Paper towel (the brown institutional ones ) overlay with Elmer's glue , as I recall . Not pretty , but functional. Seems like there usta be "recone kits" but I never fooled with 'em .

KG4CGC
01-21-2011, 02:38 PM
Paper towel (the brown institutional ones ) overlay with Elmer's glue , as I recall . Not pretty , but functional. Seems like there usta be "recone kits" but I never fooled with 'em .
I agree with this except for the Elmer's glue part. I would suggest something that retains flexibility. It should also give the speaker a sweeter, non raspy tone.
Anyone have something to add or subtract to soft glue vs hard glue in this application?

w2amr
01-21-2011, 02:59 PM
Take an old speaker and cut out a piece to use as a patch. Remove it from the same general area that has to be repaired so it has close to the same contour. Cover the bottom of the patch with RTV silicone and put it over the crack/hole. I have done several like this and it works fine.

NA4BH
01-21-2011, 03:03 PM
I took it apart and cleaned everything (dirty/dirty/dirty). Re-soldered the antenna wires. The solder that was there was like JB weld :lol: , but got it cleaned and installed new wires. Lubed it up. And it still works :lol: :wiggle: . Everything looks good, so off to the shelf until speaker repair time.

List of tubes inside:

128Q7
50L6
35Z5
12BD6

KG4CGC
01-21-2011, 03:11 PM
Point to point wiring makes replacing caps and resistors with modern counterparts as easy as flossing teeth. My only real concerns would be in the power supply area and if a toxic rectifier was used. I want to say selenium but I don't think that's it. You could replace that with about $5 worth of parts from Rat Shack.

I've seen a 455khz alignment done on YouTube and it looks easy with a sig gen. If it sounds like it's pulling in tons of stations then you could skip that step.

w2amr
01-21-2011, 03:38 PM
I took it apart and cleaned everything (dirty/dirty/dirty). Re-soldered the antenna wires. The solder that was there was like JB weld :lol: , but got it cleaned and installed new wires. Lubed it up. And it still works :lol: :wiggle: . Everything looks good, so off to the shelf until speaker repair time.

List of tubes inside:

128Q7
50L6
35Z5
12BD6

Good news Bob. I found the Rider schematic, alignment procedure, parts list and dial string diagram for your radio. Give me an E mail address and I'll send it along.

W5GA
01-21-2011, 03:58 PM
Looks like the available recone kits are all brand specific.

WØTKX
01-21-2011, 04:23 PM
Agreed on the silicone glues for patching cones... it works. You can thin it with a little water, and paint it on. Rubber cement works well too, but thin it... you want the patch to work, adding as little mass to the cone as possible.

Sometimes the coil in the speaker is used as a choke for the power supply, but if that is not the case, you may be able to find an easy replacement. Of course, redoing the power supply and improving it will be pretty easy, and then... any decent speaker that will fit will work. A simple thin masonite "gasket" can help if it's an odd size. It's amazing how good they sound with a coaxial speaker.

W5RB
01-21-2011, 05:41 PM
BTW , if nobody's mentioned it yet , this is probably a "hot chassis" transformerless design , with one side of the line connected to the chassis . Use appropriate caution when pokin' around while it's plugged in .

Thinkin' about it maybe instead of Elmer's we used corona dope , which'd be consistent with RTV or rubber cement .

kd8dey
01-21-2011, 05:56 PM
Are there any tricks to repairing an old speaker that has cracks in the paper?

There are shops around that specialize in re coning a speaker but I have never needed that service.

Too bad I'm not set up in my personal basement lab of Doom and Pepsi cola. or I would be interested in taking a look at such an older radio just for giggles.

I've got a LCR meter along with analog & digital vom to check for out of tolerance parts & tube tester assorted hand & soldering/desoldering tools at home BUT no workbench & crappy lighting.

I've got a printer paper supply box full of unsorted 1-2 watt carbon comp resistors that the school lab was throwing out and was able to "salvage" :)

(also within a couple of miles of mendelsons which has a tester and "Tube Room" & within 15-20 minutes of midwest surplus.

Took this quarter off from "Skool" (ole lady not too good right now. she just had surgery to get ready for dialysis)or I would have access to an O-scope & freq generator & Counter...........

NA4BH
01-21-2011, 08:32 PM
I have acquired the speaker paper and will get said flexible adhesive in the morning.

n2ize
01-22-2011, 01:09 AM
Okay. With a radio that old the first thing I would advise you do is to "recap" it. In other words replace all the old electrolytic and wax paper condensers. Spray clean the potentiometers and variable condensers. Then see how it plays. If it plays okay then most likely the tubes are fine. If not then you might want to try re-tubing it as well. It helps if you can get a schematic for it.

What type of radio is it. Does it run off the wall AC current or, does it run off batteries (some old tube radios did). If it runs off AC then it probably uses a selenium rectifier or a single tube rectifier. Selenium rectifiers can sometimes be problematic but they are easily replaced with silicone rectifiers. Sometimes however you need to add a current limiting resistor when making such a replacement. Otherwise it probably uses a single tube rectifier which usually last forever. In any case since the radio works the rectifier is probably okay. Just replace the filter caps.

You might find the following link handy for parts such as tubes, condensers, speakers, grill cloth, dial cords, restoration materials, etc.

http://www.tubesandmore.com/

You can also find many component parts at the standard outlets, i.e. Allied, Mouser, Digi-Key, etc.

Fixing it up yourself is a great way to go and is not that hard. Plus its rewarding. The great part about old radios is that they are easy to work on once you gain familiarity with them. Stick with it and don't give up. And, feel free to ask questions here. George, Myself, and others can help talk you through it.

n2ize
01-22-2011, 01:15 AM
I took it apart and cleaned everything (dirty/dirty/dirty). Re-soldered the antenna wires. The solder that was there was like JB weld :lol: , but got it cleaned and installed new wires. Lubed it up. And it still works :lol: :wiggle: . Everything looks good, so off to the shelf until speaker repair time.

List of tubes inside:

128Q7
50L6
35Z5
12BD6

Are you sure that top one is not a 12BQ7 ? It's common use is RF amp. I believe it's a 2x2 triode. If you need to replace it you'll probably find the 12BQ7A which is equivalent.

n2ize
01-22-2011, 01:19 AM
BTW which "Airline" do you have. I believe MW released several versions under that name over the years.

w2amr
01-22-2011, 04:14 AM
I have acquired the speaker paper and will get said flexible adhesive in the morning.
Good advise from brother John. Looking at the schematic I would replace the 3 electrolitic caps C-13, C-14, C-15. This should eliminate any hum. If the .01's .02's and .05's in the radio are those stinking waxed paper caps, it would be a good idea to replace them with new orange drops.

N4VGB
01-22-2011, 12:44 PM
128Q7
50L6
35Z5
12BD6



And that tube lineup totals 109vac, which was perfect for the standard 105-110vac of the day, back then. Just looked at one of my AC outlets with a DVM and I'm on 124vac today, it floats from 122-126vac according to the load on the HV primary out here. Not so good for an old AC/DC radio. I'm betting yours is about the same. Very small cased variacs with single outlet show up cheap at hamfests and on eBay all the time. Few are interested in them because of their 1 amp or less rating, grab yourself one and set it on 110vac for Mom's old radio. It sounds like the kind of keepsake that I'd want to protect.

The 35Z5 rectifier tube was specifically designed for use in this type set. The filament in it serves as a soft start for the rest of the tube filament string.

Look at the AC line cord plug, I'm betting it's non polarized and that's OK. Plug it in one way and the chassis is AC hot all the time and you're turning on & off the neutral AC current return path, plug it in the other way and your chassis is cold being on the neutral side and you're turning on & off the AC hot. Learn which way to plug it in for the chassis to be on the neutral side and keep it that way. These old AC/DC sets have killed more bench techs than anything else I can think of, be very careful and aware at all times.

The best speaker glue I've ever used comes from AES, I don't recall the name of the stuff right now.

KC2UGV
01-22-2011, 01:09 PM
Take an old speaker and cut out a piece to use as a patch. Remove it from the same general area that has to be repaired so it has close to the same contour. Cover the bottom of the patch with RTV silicone and put it over the crack/hole. I have done several like this and it works fine.

So, what do you do when you get around to restoring the speaker you just sacrifice :lol:

w2amr
01-22-2011, 02:32 PM
So, what do you do when you get around to restoring the speaker you just sacrifice :lol:Donors never get restored.:mrgreen:

w2amr
01-22-2011, 02:32 PM
And that tube lineup totals 109vac, which was perfect for the standard 105-110vac of the day, back then. Just looked at one of my AC outlets with a DVM and I'm on 124vac today, it floats from 122-126vac according to the load on the HV primary out here. Not so good for an old AC/DC radio. I'm betting yours is about the same. Very small cased variacs with single outlet show up cheap at hamfests and on eBay all the time. Few are interested in them because of their 1 amp or less rating, grab yourself one and set it on 110vac for Mom's old radio. It sounds like the kind of keepsake that I'd want to protect.

The 35Z5 rectifier tube was specifically designed for use in this type set. The filament in it serves as a soft start for the rest of the tube filament string.

Look at the AC line cord plug, I'm betting it's non polarized and that's OK. Plug it in one way and the chassis is AC hot all the time and you're turning on & off the neutral AC current return path, plug it in the other way and your chassis is cold being on the neutral side and you're turning on & off the AC hot. Learn which way to plug it in for the chassis to be on the neutral side and keep it that way. These old AC/DC sets have killed more bench techs than anything else I can think of, be very careful and aware at all times.

The best speaker glue I've ever used comes from AES, I don't recall the name of the stuff right now.Hey Mack, welcome back.

N4VGB
01-22-2011, 03:40 PM
Hey Mack, welcome back.

You should have taken that Chevelle to Barrett-Jackson this year, '70s Chevelles have brought the highest prices I've ever seen on them this time around. :yes:

Apparently I was "back" a while before I knew of it.:lol: Now the other members can get mad at you for informing me of that fact!:lol:

Just thought I'd drop that post before Rob fried himself or Mom's radio.;)

w2amr
01-22-2011, 03:59 PM
You should have taken that Chevelle to Barrett-Jackson this year, '70s Chevelles have brought the highest prices I've ever seen on them this time around. :yes:

Nah, I think I'll hold on to it for a while.:mrgreen:

KG4CGC
01-22-2011, 04:03 PM
Nah, I think I'll hold on to it for a while.:mrgreen:
George, the model specific to the 1970 model year is what they were after. The later models, not yet.

w2amr
01-22-2011, 04:26 PM
George, the model specific to the 1970 model year is what they were after. The later models, not yet.
The 70 LS-6 Maybe. 68 to 72 Chevelles are basically the same car. I also see the 71s and 72s going for good prices. The 73s and up , forget about it.

N4VGB
01-22-2011, 04:52 PM
The 70 LS-6 Maybe. 68 to 72 Chevelles are basically the same car. I also see the 71s and 72s going for good prices. The 73s and up , forget about it.

You're still charitable I see.:whistle:

N5RLR
01-22-2011, 06:39 PM
...Look at the AC line cord plug, I'm betting it's non polarized and that's OK. Plug it in one way and the chassis is AC hot all the time and you're turning on & off the neutral AC current return path, plug it in the other way and your chassis is cold being on the neutral side and you're turning on & off the AC hot. Learn which way to plug it in for the chassis to be on the neutral side and keep it that way. These old AC/DC sets have killed more bench techs than anything else I can think of, be very careful and aware at all times.
One trick is to cut a slit in the end of the plug prong that goes to the wider slot [neutral]. Next, open the slit slightly with a screwdriver, expanding the prong end. Then, flow solder into the gap so created and after cooling file the sides of the prong to allow it to fit into an outlet.

Also, for the input-voltage difference, determine the current draw of the set at its "nominal" voltage, then calculate and install a resistor to allow it to run comfortably at modern mains voltage. :)

N4VGB
01-23-2011, 01:55 AM
Also, for the input-voltage difference, determine the current draw of the set at its "nominal" voltage, then calculate and install a resistor to allow it to run comfortably at modern mains voltage. :)



Yep that would probably work great with this low of a current draw. I had problems with ham rcvrs using that method, too much current draw resulting in some very hot resistors. I try to avoid adding heat to vintage tube ham gear, most of it generates plenty of heat already!

KG4CGC
01-23-2011, 06:42 AM
The 70 LS-6 Maybe. 68 to 72 Chevelles are basically the same car. I also see the 71s and 72s going for good prices. The 73s and up , forget about it.
I did watch the auctions and I'm going by what the announcers told the viewing audience.

w2amr
01-23-2011, 06:56 AM
I did watch the auctions and I'm going by what the announcers told the viewing audience.
Oh, ok. Other than the LS-6 package, I just don't understand what would make a 70 anymore valuable than a 69 or 71.

rot
01-23-2011, 08:30 AM
Cool thread!
I'd love to revamp one one of these days.
Thanks.
rot

w2amr
01-23-2011, 09:08 AM
Here is a Philco I did for a guy last winter.
3867
3868

W5GA
01-23-2011, 09:58 AM
Oh, ok. Other than the LS-6 package, I just don't understand what would make a 70 anymore valuable than a 69 or 71.
One of my older brothers had one of these back in the day. Car was brutal!

w2amr
01-23-2011, 11:36 AM
One of my older brothers had one of these back in the day. Car was brutal!Oh yeah, the back tires didn't last long.

N4VGB
01-23-2011, 03:17 PM
Oh yeah, the back tires didn't last long.

If the back tires last very long it's a wimp car or the driver is.

w2amr
01-23-2011, 03:31 PM
If the back tires last very long it's a wimp car or the driver is.You should see how my 383 lights em up.:agree:

N4VGB
01-23-2011, 06:27 PM
You should see how my 383 lights em up.:agree:

You can always tell a guy that actually uses his hot rod. The back tires show a funny looking wavy pattern of melted rubber and the wheel wells show rubber specks.:shhh:

K5MIL
01-23-2011, 07:28 PM
I'll give it a try, but when the Eastern Seaboard is wiped off the map................. :lol:

It is Model 84BR-1503

Schematics for old radios can be found at: http://www.nostalgiaair.org/

Replace the electrolytic and paper capacitors. The on/off switch switches the floating B minus (common). If you want to install a polarized plug for safety, change the switch so that it switches the hot side of the AC going to the rectifier, otherwise a polarized plug doesn't help reduce any shock hazard.

Those dryer sheets the ladies throw in the clothes dryer can be used to patch a torn speaker. Use fabric glue as it will remain flexible.

http://radioremembered.org

w2amr
01-24-2011, 03:34 AM
You can always tell a guy that actually uses his hot rod. The back tires show a funny looking wavy pattern of melted rubber and the wheel wells show rubber specks.:shhh:I have been taking it easy untill I get the hardened axles installed. I got a good deal on this kit that I bought last month.
http://www.autopartswarehouse.com/details/QQChevroletQQChevelleQQRugged_RidgeQQAxle_ShaftQQ1 9681972QQ12109.html?apwcid=P1135867996W43b3f85c7ab 9e&apwid1DORj3f
Now all I need is decent WX to arrive.

w2amr
01-24-2011, 03:38 AM
Those dryer sheets the ladies throw in the clothes dryer can be used to patch a torn speaker. Use fabric glue as it will remain flexible.

http://radioremembered.orgI guess the key is to find an adhesive that will stick to the paper and still remain a bit flexible.

W1GUH
01-24-2011, 12:56 PM
Hey, if you can pick up Cousin Brucie in 77 or the Good Guys on WMCA, let me know. Or even better, the Dennision, the Mens' Clothier, Rte. 22 in Union, NJ commercials, THAT'd make a BC radio worth having these days.

Well, you can always use it as a Conelrad Monitor. What? No more Conelrad? Oh, the inhumanity!

W3WN
01-24-2011, 03:57 PM
Hey, if you can pick up Cousin Brucie in 77 or the Good Guys on WMCA, let me know. Or even better, the Dennision, the Mens' Clothier, Rte. 22 in Union, NJ commercials, THAT'd make a BC radio worth having these days.

Well, you can always use it as a Conelrad Monitor. What? No more Conelrad? Oh, the inhumanity!


The most listened to station in the nation, MusicRadio 77, W A B C New York! cue: sounder
This is... the American Contemporary Radio Network and on with 5 minutes of news.

That and the opening to Jean Shepard's 45 minutes of talk on WOR, every night at 10:15. Somethings you just don't forget.

KA5PIU
01-26-2011, 12:29 AM
Hello.

I have looked at the 5 tube AC/DC and safety and came up with my own solution.
First, the filament circuit uses the average power of the AC line, and yes, 105 volts is right.
Put this in series with the filament string and all is well.
http://www.donsbulbs.com/cgi-bin/r/b.pl/fuselamp|12v|150ma|31mm|6mm.html
A resistor will also work but this puts out light. ;)
If you want to replace the rectifier with a diode, go for a more common 28 volt 150mA aircraft panel lamp.
You will have enough light to read by.
For the safety aspect I use a 3 prong grounded plug, even if I am going to use only 2 conductor cord as the ground pin acts as in index pin.
But from a safety standpoint it is best to use 3 conductor cord.
If you are going to use an external antenna terminal, ignore what the schematic says about the capacitor and use this.
http://www.justradios.com/safetytips.html
If you really want to push safety use an IEC connector in the radio and a 3 wire cordset.

w2amr
01-30-2011, 03:13 PM
Anything new to report on the project Bob?

NA4BH
01-30-2011, 06:58 PM
It's all cleaned up. Speaker was repaired with the RTV and old speaker paper. Works great and sounds great. I talked to my Mother about it yesterday and she is thrilled about it. She also wanted me to tell y'all thanks for your guidance and help with "Her" old radio. Also, a BIG thanks from me. When time allows, I will probably open it back up and do some more checking. But right now, it's working, she's happy, and I didn't blow it up. :clap:

w2amr
01-31-2011, 03:40 AM
It's all cleaned up. Speaker was repaired with the RTV and old speaker paper. Works great and sounds great. I talked to my Mother about it yesterday and she is thrilled about it. She also wanted me to tell y'all thanks for your guidance and help with "Her" old radio. Also, a BIG thanks from me. When time allows, I will probably open it back up and do some more checking. But right now, it's working, she's happy, and I didn't blow it up. :clap:
Good job Buddy. :clap::-D

w2amr
01-31-2011, 06:50 AM
How about posting a picture, I would love to see it.

W1GUH
01-31-2011, 12:28 PM
It's all cleaned up. Speaker was repaired with the RTV and old speaker paper. Works great and sounds great. I talked to my Mother about it yesterday and she is thrilled about it. She also wanted me to tell y'all thanks for your guidance and help with "Her" old radio. Also, a BIG thanks from me. When time allows, I will probably open it back up and do some more checking. But right now, it's working, she's happy, and I didn't blow it up. :clap:

Whattaya listening to on it?