These pictures are scanned from the 1950 edition of Atkinson's Telephony, a two-volume set which was considered the "bible" of the British telephone system for many years, and is still one of the best overall references for the old SxS days of the U.K. telephone network.



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More to follow later.....

Paul: Isn't it unbelievable how far technology has come in just 50 years or so? Can you imagine with today's cost of real estate how much all of that space would cost now? I also wonder if back in those days when everybody smoked if they did it in those battery rooms!

Thanks for the pics.

Well, the gentleman in the fourth pic appears to be smoking! BTW, the battery casings appear to be wood with dovetailed corners.

What is the 'Pilot' battery in pic 4 Paul?

Great photo's !
Well made good quality equipment.
An enjoyment to see, instead of all the non repairable cheap nasty plastic c%#p we see all too often.

Thanks for posting these
Regards, Raymond

There's a substantial amount of empty space in a lot of C.O. buildings now. Look inside even something as recent as a 1970s building which originally housed a TXE2 * and now that they're just housing a digital remote concentrator unit there's a lot of empty space in the main apparatus room.

* TXE2 = Telephone eXchange Electronic No. 2, something like the American #1 ESS in overall design.



They are! Click here for a page which describes some of the different cell construction methods.



Most likely a separate battery supply for the pilot indicators used to signal various calling and alarm conditions in the building. For example, on night service the manual board might have been switched so that incoming calls not only illuminate the calling lamp over the jack itself, but also sound a buzzer and/or illuminate a master pilot lamp at the end of the suite to draw attention.

This battery bank would have been an older installation even in 1950. Some of the earlier manual exchanges used 22 or 40V, and quite a number would have still been in service at that time. 50V became the norm in later years, and of course for automatic switching.

Some more scans:



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These pages explain the operation of the drum-switch regulator. The second link includes the full-size photo and control-circuit schematic:

Drum switch regulator, 1

Drum switch regulator, 2

Drum switch regulator, 3