Telephone Magneto - UK Vintage Radio Repair and Restoration Discussion Forum

McMurdo · 15th Mar 2011, 9:32 pm

Does anyone know anything about my desktop magneto I have?

Dave Moll · 15th Mar 2011, 9:44 pm

It should have three terminals inside, two of which are connected to the magneto and the other makes a circuit with one of these when the handle is NOT being turned. When the handle is turned, it should generate a telephone ringing current.

There's not really much else to say.

McMurdo · 15th Mar 2011, 9:52 pm

It does, and the braided flex is 3-core with red, green and yellow cotton ends.

I incorporated it into a house telephone when I was a kid.

I just wondered how old it was and where it would be originally used.
The handle and knob is the same as one on my Ericcson skeleton phone.

russell_w_b · 15th Mar 2011, 11:10 pm

Quote:

Originally Posted by McMurdo

I just wondered how old it was and where it would be originally used.

I have one, and I'm guessing 1920s up until the improved magneto 26A with the Alnico magnet superseded it in the late 1930s - early 1940s. I think they'd have been used as an appendage to a dial telephone for local signalling, but not entirely sure.

The later bakelite magneto sets were sometimes used with a handset on a pendant rest and separate bell, so perhaps your magneto was so arranged?

russell_w_b · 15th Mar 2011, 11:48 pm

Further to my earlier post, I just dug mine out for a look. It is stamped: 'No:4033' then 'GPO W20 No:4CN'.

The 4CN fits in with its designated type and the GPO is self-evident, but the rest? A clue, perhaps? More interestingly was a piece of oiled paper folded up inside, with an ink-drawn diagram suggesting main and extension telephones and generators. See pics attached.

McMurdo · 16th Mar 2011, 8:28 pm

Mine is stamped 3AN GNH and then 34 and then a horizontal 'I' and stamped over it is a right-way up 'J', looks like a monogram or cipher. Mine also has 4 rather than 3 magnets.

russell_w_b · 16th Mar 2011, 9:40 pm

Quote:

Originally Posted by McMurdo

Mine also has 4 rather than 3 magnets.

Looks like yours contains a Generator No:8A rather than the 4C in mine. Maybe yours is older?

15th Mar 2011, 9:32 pm	#1
McMurdo Dekatron Join Date: Jun 2009 Location: Staffordshire Moorlands, UK. Posts: 5,273	Telephone Magneto Does anyone know anything about my desktop magneto I have? Attached Thumbnails __________________ Kevin Last edited by Dave Moll; 15th Mar 2011 at 9:41 pm. Reason: moved from unrelated thread

15th Mar 2011, 9:44 pm	#2
Dave Moll Dekatron Join Date: Feb 2005 Location: West Cumbria (CA13), UK Posts: 6,130	Re: Telephone Magneto It should have three terminals inside, two of which are connected to the magneto and the other makes a circuit with one of these when the handle is NOT being turned. When the handle is turned, it should generate a telephone ringing current. There's not really much else to say. __________________ Mending is better than Ending (cf Brave New World by Aldous Huxley)

15th Mar 2011, 9:52 pm	#3
McMurdo Dekatron Join Date: Jun 2009 Location: Staffordshire Moorlands, UK. Posts: 5,273	Re: Telephone Magneto It does, and the braided flex is 3-core with red, green and yellow cotton ends. I incorporated it into a house telephone when I was a kid. I just wondered how old it was and where it would be originally used. The handle and knob is the same as one on my Ericcson skeleton phone. __________________ Kevin

15th Mar 2011, 11:48 pm	#5
russell_w_b Dekatron Join Date: Jul 2007 Location: Penrith, Cumbria, UK. Posts: 3,687	Re: Telephone Magneto Further to my earlier post, I just dug mine out for a look. It is stamped: 'No:4033' then 'GPO W20 No:4CN'. The 4CN fits in with its designated type and the GPO is self-evident, but the rest? A clue, perhaps? More interestingly was a piece of oiled paper folded up inside, with an ink-drawn diagram suggesting main and extension telephones and generators. See pics attached. Attached Thumbnails __________________ Regds, Russell W. B. G4YLI. Last edited by Dave Moll; 16th Mar 2011 at 11:26 am. Reason: (unnecessary) broken quote removed

16th Mar 2011, 8:28 pm	#6
McMurdo Dekatron Join Date: Jun 2009 Location: Staffordshire Moorlands, UK. Posts: 5,273	Re: Telephone Magneto Mine is stamped 3AN GNH and then 34 and then a horizontal 'I' and stamped over it is a right-way up 'J', looks like a monogram or cipher. Mine also has 4 rather than 3 magnets. Attached Thumbnails __________________ Kevin