Home » Audio » Radio » Airline 62-2704 Need Help (Need help finding information on this radio)
Airline 62-2704 Need Help [message #63270] Mon, 28 June 2010 17:46 Go to next message
Encryptor is currently offline  Encryptor
Messages: 16
Registered: June 2010
Location: Central Bridge, NY
Chancellor
I bought an Airline 62-2704 for $25 but I'm having trouble finding information for it. I think it's in decent shape but have no idea if it works. Several wires were disconnected when I got it. The label inside has a different layout than the actual chassis does. I've looked through 100's of pages in the Rider's books and found a couple that match the label but haven't been able to find one that matches the actual chassis. One of the tubes is labeled RCA Electron Tube 8-52 and I couldn't find much info on this tube either. Any help would be greatly appreciated.

http://www.flickr.com/photos/51539872@N05/4744040178/

http://www.flickr.com/photos/51539872@N05/4743402273/

http://www.flickr.com/photos/51539872@N05/4744040022/

Bill
Re: Airline 62-2704 Need Help [message #63272 is a reply to message #63270] Mon, 28 June 2010 21:23 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18787
Registered: January 2001
Illuminati (33rd Degree)

That's awesome, Bill! I have a couple of Montomery Ward radios and in each case, the only way to find the schematic was to match the chassis by visual inspection. You just have to look through the whole Rider catalog, scanning for chassis that look like yours by physical layout and matching tube sets. It's a monotonous job, but it's the only way to do it. Montgomery Ward bought chassis from an OEM and had cabinets made for them. Mine were RCA chassis, for what it's worth.

Re: Airline 62-2704 Need Help [message #63274 is a reply to message #63272] Mon, 28 June 2010 21:48 Go to previous messageGo to next message
Encryptor is currently offline  Encryptor
Messages: 16
Registered: June 2010
Location: Central Bridge, NY
Chancellor
Have you seen many where the diagram inside the cabinet looked different than the actual chassis? I was speaking to my brother who is into ham radios and he said they didn't always put everything on the diagram, usually just the tubes. Is that true? Thanks for the reply.

Bill
Re: Airline 62-2704 Need Help [message #63277 is a reply to message #63274] Tue, 29 June 2010 09:27 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18787
Registered: January 2001
Illuminati (33rd Degree)

Yeah, that diagram is mostly for user-service, an aid to help identify tubes by layout. Usually, they show transformers and other features as sort of a reference point, but being a rectangular chassis, you only really need to show tube locations. I have a few radios with labels like that.

Re: Airline 62-2704 Need Help [message #63279 is a reply to message #63277] Tue, 29 June 2010 15:35 Go to previous messageGo to next message
Encryptor is currently offline  Encryptor
Messages: 16
Registered: June 2010
Location: Central Bridge, NY
Chancellor
Ok. Thanks for the help.

Bill
Re: Airline 62-2704 Need Help [message #63280 is a reply to message #63279] Tue, 29 June 2010 15:43 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18787
Registered: January 2001
Illuminati (33rd Degree)

In your first post, you said there were some disconnected wires. Have you tried to identify the wires and reconnect them? Should have a couple for antenna/ground, probably four for the speaker (voice coil +/- and field coil +/-) and then of course the power cord.

Does it power up? Do the filaments glow?

Re: Airline 62-2704 Need Help [message #63281 is a reply to message #63280] Tue, 29 June 2010 17:49 Go to previous messageGo to next message
Encryptor is currently offline  Encryptor
Messages: 16
Registered: June 2010
Location: Central Bridge, NY
Chancellor
I know what they are but not sure how to hook them up. Particularly the antenna wires. There are 3 of those. I think a yellow, a green and I think a black. The audio cable from the phono was ripped out of the rca jack. I haven't tried to plug it in yet. If you look at the picture of the chassis there is a small transformer on the right side that has a bundle of 3 or 4 wires coming out of it that have been taped up. I'm not sure what they are for or if they are even used for this radio. I believe there are only 2 for the speaker.

I do have a couple more questions if you don't mind.

Would you look for a schematic that matches the diagram or the actual chassis?

I understand MW had different OEM's manufacture the radio's for them. Did they use the major supplier's for this or did they just use anyone? There are so many different manufacturers that made radios from that time period.
Re: Airline 62-2704 Need Help [message #63282 is a reply to message #63281] Tue, 29 June 2010 18:35 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18787
Registered: January 2001
Illuminati (33rd Degree)

I'm not sure how many manufacturers Montgomery Ward used as OEM's for their radios. I personally have only seen RCA, so MW may have bought chassis only from them, I suppose. But I expect they had other manufacturers bid too.

I'd be happy to look for a schematic for you but my Rider CD's are packed away. However, I'll try to make time to unpack them and look soon. There are lots of schematics in there though, and all you can do is look through them one at a time, so you'll definitely owe me a steak dinner. Very Happy

As for the rest of your questions, the wires coming from the transformer are probably speaker connections. Two are probably for the voice coil and two are probably for the field coil. Look at the speaker and see if there are four wires, or a connector with four lugs. The old speakers were made that way, with a field coil that energizes an electromagnet instead of a fixed magnet on the back. This coil also serves double-duty as a power supply filter.

The three wires you think are antenna could be that, I suppose, a balanced pair and a ground. But usually the antenna connection for AM radio is only two wires, (antenna and ground). If AM/FM there would be a separate AM and FM line, but this is only an AM radio. Also, I see from the image of the label you uploaded that it shows a single wire for the antenna (chassis is probably ground). So I am wondering why there are three wires, and I really think they are probably something else.

Re: Airline 62-2704 Need Help [message #63283 is a reply to message #63282] Tue, 29 June 2010 18:46 Go to previous messageGo to next message
Encryptor is currently offline  Encryptor
Messages: 16
Registered: June 2010
Location: Central Bridge, NY
Chancellor
Which schematic would you look for? The diagram or the chassis? I've found a couple that match the diagram but not the chassis.

Would there be three wires because of the shortwave portion?

I just looked and there isn't a speaker in it unfortunately.
Re: Airline 62-2704 Need Help [message #63284 is a reply to message #63283] Tue, 29 June 2010 21:44 Go to previous messageGo to previous message
Wayne Parham is currently offline  Wayne Parham
Messages: 18787
Registered: January 2001
Illuminati (33rd Degree)

If it has shortwave, that might be it, I suppose. Could be one antenna lead for medium wave and another for shortwave. I'm not sure I've ever seen a radio made that way - most have a single antenna for shortwave and medium wave - but I suppose maybe yours is different. But I still think those three wires are for something else because the label shows only one antenna wire.

The document set for each radio usually includes schematic, chassis layout and alignment instructions.

I expect the missing speaker was a field coil unit and so you'll need to identify the pair of wires that go to the voice coil and the field coil. The voice coil output pair can usually be run to a modern fixed-magnet speaker as long as the field coil pair is run through a coil, like 5mH or so, something like that. The radio probably won't work without a field coil connected, because the plate voltage for the tubes goes through it.

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