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Vintage Telephony and Telecomms Vintage Telephones, Telephony and Telecomms Equipment |
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17th May 2020, 9:51 pm | #1 |
Heptode
Join Date: Mar 2008
Location: Camberley, Surrey, UK.
Posts: 800
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Telephone exchange jackfield help
We are restoring a 1963 manual "control Line" telephone exchange as part of the BBC outside broadcast van.
The problem revolves round the jack cords which, to quote from the handbook, are "self retracting" Normally the cords would retract by gravity but in this installation there is no room for that. I visualise some sort of coiling arrangement, there is only about 6 inches under the desk top for this. So the question is was there a "standard" device for this or did Pye make their own?? The telephone control line system is better known as magneto ringing and the panel has a set of dolls eye indicators for incoming calls. More can be found on the projects website www.mcr21.org.uk |
18th May 2020, 9:45 am | #2 |
Heptode
Join Date: Jan 2008
Location: Hakadal, Norway
Posts: 640
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Re: Telephone exchange jackfield help
This looks like a great project. Several field exchanges has solutions for that, so the first one I think about is the US SB 22 PT
Here is a link with good pictures. The jack is made to accept ordinary 1/4" stereo plugs, but the wires has extremely small diameter. (2 mm??) http://www.signalcenter.com/commo/eb...d1/3cord1.html Another I know is the German one with shorter plugs, but a more normal wire diameter: https://www.finn.no/bap/forsale/ad.h...kode=155353583 (The seller in this deactivated ad has tried to sell a number of these for some time, and may have more of them stored. ) dsk PS How many units do you need for this project (no of coils)? DS Last edited by dagskarlsen; 18th May 2020 at 10:06 am. Reason: adding info |
18th May 2020, 3:53 pm | #3 | |
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Re: Telephone exchange jackfield help
Quote:
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18th May 2020, 3:54 pm | #4 |
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Re: Telephone exchange jackfield help
Or did they go sideways with a spring and pully?
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19th May 2020, 9:56 am | #5 |
Heptode
Join Date: Mar 2008
Location: Camberley, Surrey, UK.
Posts: 800
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Re: Telephone exchange jackfield help
There are 15 cord retraction units closely spaced there are no holes and beneath there are amplifiers and power supplies.
The American device in the first link by dsk is the sort of principle I visualise, but with a jack at both ends of the device. Pye, who made the OB vans, would have needed in total 150 of these so may have made them in their own factory, or was there a GPO unit that they could have used back in 1963? |
19th May 2020, 12:12 pm | #6 | |
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Re: Telephone exchange jackfield help
I wondered about the GPO/POT PMBX4, but when looking for that I found this which looks much more likely:-
https://switchboard-uk.tumblr.com/po...-manual-branch Quote:
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
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19th May 2020, 3:37 pm | #7 |
Heptode
Join Date: Mar 2008
Location: Camberley, Surrey, UK.
Posts: 800
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Re: Telephone exchange jackfield help
That looks to be just the right sort of thing, I rather think finding some spare cassettes will be difficult, but at lease we know what we are looking for and it did exist!
Thanks very much for the link. Brian |
19th May 2020, 6:21 pm | #8 |
Heptode
Join Date: Jan 2008
Location: Hakadal, Norway
Posts: 640
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Re: Telephone exchange jackfield help
Looks better than my exsamples.
dsk |
20th May 2020, 8:57 am | #9 |
Heptode
Join Date: Jul 2006
Location: Winchester, Hampshire, UK.
Posts: 636
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Re: Telephone exchange jackfield help
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