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-   -   Video of last manual exchange in London (https://www.vintage-radio.net/forum/showthread.php?t=167459)

Hampus 2nd Jun 2020 10:56 pm

Video of last manual exchange in London
 
I found this video on BT's site, it depict the last manual exchange in London beeing replaced with an automatic exchange.

It's fifteen minutes but i think it was well spent time watching it. It is a somewhat bittersweet, sometimes even emotional story. Especially the moment when the old exchange is disconnected after many years of service and suddenly becomes just a room full of old junk.

http://home.bt.com/video/relive-the-...91364117408068

PsychMan 3rd Jun 2020 2:21 pm

Re: Video of last manual exchange in London
 
Interesting video. "2000 pair cable" :D

The previous site of the company I work for was a BT exchange building, built sometime in the 50s or early 60s. A big section on the 1st floor was rented out to us as a data centre room, with some office space next to it.

The winching point where they bring up the huge cable drum in that video looks identical to the one at our first floor data centre room. I suppose that's what it was there for!

high_vacuum_house 3rd Jun 2020 8:10 pm

Re: Video of last manual exchange in London
 
That is a cracking film. Surprised that manual exchanges were still operating so late. I am surprised that they went for an electromechanical exchange rather than an all electronic exchange. I presume that it was quickly superseded by a solid state exchange.

Wonder how many of the dial less telephones were saved and the old manual exchange equipment was saved? Presumably still all old junk then and not worth saving.

Christopher Capener

Dave Moll 3rd Jun 2020 9:11 pm

Re: Video of last manual exchange in London
 
One thing that surprised me was the use of wedges to disconnect the lines from the manual exchange prior to using a second set to connect them to the automatic.

In footage I've previously seen of electromechanical exchanges being replaced by electronic ones, the disconnection was performed by rows of technicians simply snipping the cables prior to the wedges being pulled to cut in the new exchange. To me, this seems the obvious approach, rather than preceding the cut-over by laboriously connecting equipment whose only purpose will be to perform that same effect of disconnecting the existing lines - unless, of course, these wedges were an integral part of the manual exchange to begin with.

cmjones01 3rd Jun 2020 9:39 pm

Re: Video of last manual exchange in London
 
Wonderful film, full of the reassuring feeling that the mustachioed, suited gentlemen of the Post Office were looking after us and making progress on our behalf. The music is a joy too.

Quote:

Originally Posted by Dave Moll (Post 1255624)
unless, of course, these wedges were an integral part of the manual exchange to begin with.

They were referred to as fuses in the manual exchange, so presumably were an integral part of it. Removing them with the cords threaded through them looked a lot quicker than cutting thousands of wire!

Chris

Trifocaltrev 3rd Jun 2020 10:17 pm

Re: Video of last manual exchange in London
 
Manual exchanges in some areas lated for a long time, Hastings and Newbury did not change until 1973/74 and I belive the very last one according to a television news article at the time, was Portree on the Isle of Skye. Also when Rainham exchange was converted I don't think the System X electronic exchanges existed.

Regards
Trevor.

Pellseinydd 3rd Jun 2020 11:05 pm

Re: Video of last manual exchange in London
 
4 Attachment(s)
Upminster (in the film) was converted c1971 and at that time the manual exchange in March 1971 had 7100 lines on it. It was converted to a Non Director crossbar exchange which had 7700 lines on it a year later. The only electronic exchanges at that time were the TXE2 (Telephone eXchange Electronic No 2).

As far as I can find out, only one manual exchange was ever converted direct from manual to electronic - a TXE2. That was 'Rhosllanerchrugog' a five position CBS2 manual exchange in a private house in Rhos Notice 'DP 1' (Distribution Pole) in the back garden of the exchange house - grey on on the right of photo. It had 893 lines on it when it changed over to a TXE2 - commissioned by guess who in 1972? The first large electronic exchange was Birmingham 'Rectory' - the first TXE4 which didn't come into service until 1976. Guess who was senior commissioning engineer there?

ex-GPO manual exchanges do survive - I have a couple. One is the CBS2 that was Braunton in Devon until late 1960's and the only surviving CS No 3 exchange out of the 475 which the GPO once had in service. It was a small 3 junctions + 20 lines (originally it had been a 3+5 when it was fitted in 1925 by David John McFarquhar the GPO engineer for the area. The operator in whose house it was, was a Miss Kathy Fullerton. Also got the centre suite from the switchboard which appears throughout this film series - the last large manual board that will ever be built as the rest of the positions were scrapped after the second series. There was nothing in them anyway as they had been stripped to get them out from their 'bunker type' location. It was the original GPO 'auto-manual' switchboard at the then newly opened Portmadoc automatic exchange in 1943 as in the black and white picture.

Pellseinydd 3rd Jun 2020 11:43 pm

Re: Video of last manual exchange in London
 
1 Attachment(s)
Quote:

Originally Posted by Dave Moll (Post 1255624)
One thing that surprised me was the use of wedges to disconnect the lines from the manual exchange prior to using a second set to connect them to the automatic.

In footage I've previously seen of electromechanical exchanges being replaced by electronic ones, the disconnection was performed by rows of technicians simply snipping the cables prior to the wedges being pulled to cut in the new exchange. To me, this seems the obvious approach, rather than preceding the cut-over by laboriously connecting equipment whose only purpose will be to perform that same effect of disconnecting the existing lines - unless, of course, these wedges were an integral part of the manual exchange to begin with.

A lot depended on the type of frame - most of the 'video' that I've seen was shot by enthusiasts in the 1990's coming to the end of electro-mechanical exchanges. I've seen all sorts of methods for the exchanges I've seen cut over between the late 1950's (mainly manual to auto at that time) to the very last cutover of an electro-mechanical exchange to digital in mid July 1995.Mentioned in '1995 here. That was an interesting one as the lines were moved over one at a time using an 'Inserter 2a' Krone tool on a 100 pair krone block! There were only 20 lines on the exchange. BT are after my video of the changeover for their website!

Dave Moll 4th Jun 2020 8:58 am

Re: Video of last manual exchange in London
 
Quote:

Originally Posted by cmjones01 (Post 1255648)
Quote:

Originally Posted by Dave Moll (Post 1255624)
unless, of course, these wedges were an integral part of the manual exchange to begin with.

They were referred to as fuses in the manual exchange, so presumably were an integral part of it. Removing them with the cords threaded through them looked a lot quicker than cutting thousands of wire!

Thanks for confirming that these were part of the exchange - so yes, making a convenient method for disconnecting en masse.

Test Desk 4th Jun 2020 9:19 am

Re: Video of last manual exchange in London
 
Quote:

Originally Posted by Dave Moll (Post 1255624)
One thing that surprised me was the use of wedges to disconnect the lines from the manual exchange prior to using a second set to connect them to the automatic.

In footage I've previously seen of electromechanical exchanges being replaced by electronic ones, the disconnection was performed by rows of technicians simply snipping the cables prior to the wedges being pulled to cut in the new exchange. To me, this seems the obvious approach, rather than preceding the cut-over by laboriously connecting equipment whose only purpose will be to perform that same effect of disconnecting the existing lines - unless, of course, these wedges were an integral part of the manual exchange to begin with.

In this case yes, but it's a good thing nothing was snipped when Cadbury replaced their electro-mechanical PABX3 with an STC Unimat 4080 back in the 80's. I had been trained to look after the new telephone system (essentially, an electronic matrix using reed delays to connect the cross-points). Cadbury had done such a good job educating the staff about all the wonderful new facilities available via their push-button DTMF phones, that on switchover day, the system kept crashing due to the number of people waiting for dial tone exceeding system parameters. The decision was made to switch back to the Old PABX 3 until more multi -frequency receivers were added to the Unimat. If I recall, at go-live 1800 extensions were connected just 8 MFR's. Another 8 were subsequently added and software tweaked resulting in a successful switchover. When the excitement died down, and traffic stats analysed, 4 MFR's were uninstalled leaving 12 in service with no detriment to the service, proving the planning for provision was correct but didn't take account of the initial enthusiasm of the users!

kalee20 4th Jun 2020 12:53 pm

Re: Video of last manual exchange in London
 
Quote:

Originally Posted by Hampus (Post 1255257)
It's fifteen minutes but i think it was well spent time watching it.

I think it is, too. Very interesting film. (The period street shots are socially interesting, too!)

Dave Moll 4th Jun 2020 2:13 pm

Re: Video of last manual exchange in London
 
I noticed that some scenes from this video re-appeared in last night's repeat of the Timeshift programme, Dial "B" for Britain: The Story of the Landline.

IanG3XYV 4th Jun 2020 2:49 pm

Re: Video of last manual exchange in London
 
It was but I lament the lack of UK design and manufacturing companies nowadays.

Pellseinydd 4th Jun 2020 3:54 pm

Re: Video of last manual exchange in London
 
Is there a British owned manufacturer of telecoms equipment these days - other than the odd specialist telephones ?

I'm sure the then GPO would only purchase UK manufactured equipment.

jjl 4th Jun 2020 4:24 pm

Re: Video of last manual exchange in London
 
I don't think so, but don't forget that STC were founded by US based Western Electric in 1883, owned by the US based ITT corporation from 1925 to 1982 and were only truly an independent British company from 1982 until they disappeared in 1991.

John

OscarFoxtrot 4th Jun 2020 5:50 pm

Re: Video of last manual exchange in London
 
Quote:

Originally Posted by Pellseinydd (Post 1255931)
I'm sure the then GPO would only purchase UK manufactured equipment.

And made sure they had multiple suppliers of compatible parts.

red16v 5th Jun 2020 8:30 am

Re: Video of last manual exchange in London
 
I used to work for Pirelli cables making, among other things paper and plastic insulated telephone cables. To be sure the GPO shared orders around the various manufacturers to make sure no monopoly developed. The CEGB were the same - but at the other end of the signal power scale!

Peter.N. 5th Jun 2020 11:00 am

Re: Video of last manual exchange in London
 
Lovely film that and very nostalgic. When we moved down to Dorset in July 1970 the Borough Green Kent exchange was still manual although they had given us phones with dials about a year earlier, so it must have been changed over soon after we left. Many of the operators had been local people some of whom I knew.

When we arrived in Charmouth we were greeted by an automatic exchange with only a few hundred subscribers.

I like the 'updated' Morris 1000 vans, in my youth the GPO ran Morris 8s with rubber front wings.

Peter

Pellseinydd 5th Jun 2020 11:49 am

Re: Video of last manual exchange in London
 
Quote:

Originally Posted by jjl (Post 1255952)
I don't think so, but don't forget that STC were founded by US based Western Electric in 1883, owned by the US based ITT corporation from 1925 to 1982 and were only truly an independent British company from 1982 until they disappeared in 1991.

John

I did say 'UK manufactured' ;) I know that STC was part of the ITT group - I worked for them in the 1970's on TXE2 and the first TXE4.

I never saw anything during my GPO days that wasn't manufactured in the UK.

red16v 5th Jun 2020 12:40 pm

Re: Video of last manual exchange in London
 
Quote:

Originally Posted by jjl (Post 1255952)
I don't think so, but don't forget that STC were founded by US based Western Electric in 1883, owned by the US based ITT corporation from 1925 to 1982 and were only truly an independent British company from 1982 until they disappeared in 1991.

John

Wasn’t STC’s telecoms cable business bought by Pirelli? In which case you could argue it eventually became an Italian company!

I recall we (Pirelli) had a contract to part supply an 18tube Co-axial cable from Martlesham to the Birmingham PO tower. (Another example of the GPO spreading contracts around). Part of the in-situ testing involved testing the frequency response of the tubes up to around the upper hundreds of MHz using TDR techniques. We had ‘cracked’ how to do it but STC couldn’t. We ended up in a agreement with them that we would TDR test their cables once they were in the ground and they tested some other specs on our cables in return.

Good fun driving around the streets of Birmingham lifting up manhole covers etc. The bacon sandwiches were great! Sorry to go OT.


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