Home » Audio » Radio » Airline 62-2704 Need Help (Need help finding information on this radio)
Re: Airline 62-2704 Need Help [message #63285 is a reply to message #63284] Wed, 30 June 2010 13:29 Go to previous messageGo to next message
Encryptor is currently offline  Encryptor
Messages: 16
Registered: June 2010
Location: Central Bridge, NY
Chancellor
As far as I can tell there is only one antenna. Doesn't mean there wasn't two at some point.

The question I was asking about the schematics is - Since the diagram and the actual chassis don't appear to match to me, would you suggest looking for the schematics for the pictured radio in the diagram or look for one that looks like the actual picture of the chassis I have? Which set should I be looking for?

Can you still get the field coil speakers? I'd like to replace it with what should be in there.
Re: Airline 62-2704 Need Help [message #63290 is a reply to message #63285] Wed, 30 June 2010 19:02 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18670
Registered: January 2001
Illuminati (33rd Degree)

You might be right about the antenna - I was going by what you said, the fact that there were three wires. I assumed you saw them as inputs to the RF input tube, through their own trimmer caps. Trace those wires back, maybe they're not antenna leads at all.

About the schematic search, I'd look for a match on the chassis and tube complement. When you have a visual match, you have the right schematics.

There are no new field coil speakers, at least not the kind for table radios. There are a few for hifi, but they're very expensive, not anything like what you'd put in a radio like this. The only way to find a field coil speaker is as a pull, a used part from something else. You can probably find one on eBay.

Re: Airline 62-2704 Need Help [message #63294 is a reply to message #63290] Thu, 01 July 2010 04:54 Go to previous messageGo to next message
Encryptor is currently offline  Encryptor
Messages: 16
Registered: June 2010
Location: Central Bridge, NY
Chancellor
Yes there are 3 wires for the antenna. Those are the only ones that were hooked up when I got it. There is a yellow, green and black and I just noticed another wire that has a small metal crimp on it that says Ant on it. It's a stiff wire like it's a solid conductor. Looking at one of the schematics I found it looks like it might be for an external antenna.

That's what I thought. I have found several that look like the diagram but none like the chassis yet.

According to a schematic I printed for a 2704A radio the speaker is a 10" PM dynamic speaker. Not sure what that means exactly.
Re: Airline 62-2704 Need Help [message #63296 is a reply to message #63294] Thu, 01 July 2010 09:31 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18670
Registered: January 2001
Illuminati (33rd Degree)

I guess you do have more than one antenna input, interesting.

About the speaker, what that means is you have a 10" driver. A "dynamic speaker" is what they call drivers with linear motor voice coils and moving cones.

Re: Airline 62-2704 Need Help [message #63303 is a reply to message #63296] Thu, 01 July 2010 19:37 Go to previous messageGo to next message
Encryptor is currently offline  Encryptor
Messages: 16
Registered: June 2010
Location: Central Bridge, NY
Chancellor
What kind of external antenna would be used on this?

Is that considered a field coil speaker?

I was looking on ebay for a "10" field coil speaker" and found 4 listed. They are not cheap to buy. The cheapest one started at $50 and has a big rip in it.

Sorry to bother you with so many questions. I'm a noob at this old radio stuff.

Bill
Re: Airline 62-2704 Need Help [message #63305 is a reply to message #63303] Fri, 02 July 2010 10:00 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18670
Registered: January 2001
Illuminati (33rd Degree)

Don't apologize! That's what this forum is for and I love chatting about old radios.

Both fixed magnet and field coil speakers are called "dynamic loudspeakers." It's kind of funny to me that they call them that, it's sort of like qualifying a car tire as a "rolling tire".

I'm not surprised that they would be $50 for a ripped one. They aren't made anymore. I would prefer a speaker with no rips, but you can fix the paper easier than you can fix a coil. Either one can be fixed - I've rewound field coils and pretty much any competent repair shop can do a recone. For older tube radios like this, I usually patch rips with diluted white glue.

For casual listening on medium wave and shortwave bands, I tend to prefer a longwire antenna. As the name suggests, it's just a very long wire. Run it as high off the ground as possible away from metal and power lines where possible.

Re: Airline 62-2704 Need Help [message #63327 is a reply to message #63305] Tue, 06 July 2010 10:32 Go to previous messageGo to next message
Encryptor is currently offline  Encryptor
Messages: 16
Registered: June 2010
Location: Central Bridge, NY
Chancellor
Ok thanks. I'll ask all the questions I come up with.

As I mentioned there are a couple on ebay. Can any field coil speaker be used in any radio?

My brother is into HAM radios. I'll have him make me an antenna for it if I can get it working.

I'm looking through the Rider books but haven't found one that matches the actual chassis yet. I'm not sure what year to look in but someone else asked about this very same radio a year or so ago in this forum and you told him then that by the tube set it was probably in the 50's so I started in the mid 40's and will go up from there and see if I can find anything.

Bill
Re: Airline 62-2704 Need Help [message #63328 is a reply to message #63327] Tue, 06 July 2010 11:11 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18670
Registered: January 2001
Illuminati (33rd Degree)

That's the best way to find the schematics. Sorry I didn't have time to get the CD's out of storage, lots going on what with a 3-year-old running around and a million little projects. Everything seems to take months longer than it should, but that's just the way it is for a few years. So anyway, I'm glad you can scan through the Rider collection yourself. That's the only way to do it.

About the field coil speakers, there are differences, but for what you're doing, all will work. There will be a variance between units on coil resistance and number of turns, some can be designed to require more current than others, but for these kinds of radios, all are in pretty much the same range. All that's required is the B+ go through the coil, and the current drawn by the set - all the tubes' anodes - is what energizes the coil. Since all are basic five or six tube radios, they all have about the same current draw. This, in turn, means all the field coils have to provide enough flux to work with the available current, making them all pretty similar. Bottom line: If the speaker works, the coils aren't open and the cone physically moves, then I would expect it to work when properly connected.

Re: Airline 62-2704 Need Help [message #63347 is a reply to message #63328] Wed, 07 July 2010 15:42 Go to previous messageGo to next message
Encryptor is currently offline  Encryptor
Messages: 16
Registered: June 2010
Location: Central Bridge, NY
Chancellor
Well I purchased a speaker. It was a Buy It Now for $65 or make an offer. I offered them $30 and it was accepted. What do you think? http://tinyurl.com/2vsdsvn

Bill
Re: Airline 62-2704 Need Help [message #63348 is a reply to message #63347] Wed, 07 July 2010 17:00 Go to previous messageGo to previous message
Wayne Parham is currently offline  Wayne Parham
Messages: 18670
Registered: January 2001
Illuminati (33rd Degree)

Excellent! It looks like it's in great shape. If it works, I think it was money well spent.

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