Guildford (Sydney) Step by Step Exchange 1993 - You Tube Videos
Once upon a time in every town, every suburb in Australia - there was a Step by Step telephone exchange.
All those exchanges. Millions of lines. Tens of thousands of employees and workers. And yet nobody. NOBODY - bothered to make a video or audio
recording of these machines for the sake of those in the future who would never get to see, hear or feel such a monster machine from the inside.
Except one. Until now hidden away . Not any more.
One day in the late '80s, Paul Matthews found a second hand Video 8 camera in the local pawn shop for, shall we say, a price too good to turn down.
In 1993, he took the little camera to Guildford Telephone Exchange, to meet a friendly Telecom employee mate who at the time worked maintaining the Step by Step section there. Never did he know that 21 years later this feeble, shaky and poorly lit Hi 8 video tape would be the only example of such material recorded in Australia - possibly worldwide.
Guildford SxS in 1993 was a hybrid. Officially it is known as a "register controlled step by step". Instead of siezing an idle 1st selector, calls out of Guildford Step were switched SR/B relay sets which in turn linked to Crossbar registers (in this case ARE11). All calls then progressed into the Crossbar network and from there most then entered the much newer adjacent digital AXE RSS stage and thence off to their destination.
Local calls within Guildford were either switched to the Crossbar subscribers withn the same exchange, or were switched back to the original SXS 3rd selectors in the Step section and decadic pulsed through 4th and Final selectors to the called subscriber.
The room in these videos features the Step by Step section of Guildford, including the subs uniselectors, the Crossbar SR/B stage and the terminating 3rd, 4th and Finals. It also features standard SxS routiners, pulse generators, tone generators, cleaning of banks, servicing of selectors and routine testing - all within a working exchange.
The official designation of Guildford in 1993 was "SR/B-2E-ABID" This means it was a SxS exchange with SR/B Crossbar 1st selector stage slaved off an ARE11 crossbar GV stage and featuring ABID (A-B-IDentification) technology.
AB-ID was a neat technology added to some SR/B exchanges in Sydney which were located alongside ARF exchanges which were converted to ARE11 in the late '70s. It allowed the SR/B relay sets to determine the identity of the exact calling line switched to them through the existing subscribers' uniselectors. This in turn allowed the ARE11 Crossbar to pass on the identity of the calling line (CLI) to higher order exchanges so individual calls can be charged and recorded separately - essential for ISD access. In effect it gave SxS customers a full suite of modern (for the time) Crossbar facilities - even touch tone dialling!
AB-ID used a series of 15kHz tone injection "Matrix" wires imposed across each of the incoming lines into the SxS section. This in turn performed a similar function to the DC marking that allows a Crossbar marker to identify a calling line in an ARF / ARE SL stage. ABID extended the life of SxS in Sydney by another 10 years of so - such that it could eventually be replaced by digital technnlogy rather than more Crossbar which at the time, was getting quite old and expensive.
This series of videos will never match the thrill of standing in the middle of a 15,000 line central city SxS exchange at busy hour. Nor even hope to invoke the emotion or thunder of being inbetween five floors of m=10 ARF Crossbar in Pitt St in 1976 at 10am on Monday morning. But it's the only thing we've got that comes close. So enjoy.
