Home:  Exchange Equipment: RELIANCE PAX, 1940's


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Donated by The Forest of Dean Railway Company where it was in use. Restored and repaired and now in fully working order. PAX stands for Private Automatic Exchange. Some parts are dated 1946.

This item can be demonstrated.

Your comments:

  • I served my apprenticeship between 74 and 79 with
    Reliance @ Birmingham. Saw quite a few of these early rotary 25 or 50 line PAX. Some pre WW2. Very well made by GEC at Coventry. Never seemed to go wrong.
    Later versions were in metal cans with pull off fronts.
    Probably still lurking in attics awaiting to be found together with their Harmer Simmonds PSU and sets of Chloride lead acid batteries.
    .......... Bryan Powell, Rugeley England, 12th of April 2020

  • What a neat little unit! I have one of those split-armature relays in my collection, and I always wondered where it came from.

    I've never seen one of these, but here's my take on it: This appears to be a 24- or 25-line exchange using 25-point uni selectors as line finders and selectors. The 24 split-armature relays in the top LH corner would be the line/cut-off relays. There may be a 25th one lurking about somewhere. The four uni selectors beneath them will be the line finders and the other four uniselectors to the right will be the selectors. The four relay groups for the connecting circuits are also on the right; three above the uniselectors and one below. The bottom RH relay group is probably the ring and tone supply. The top LH relay in this group is certainly a ringing vibrator.

    The rest of the relays are harder to identify. I'd dearly love to see some circuit diagrams for this beauty.

    .......... George Winter, Sydney, Austrealia, 31st of December 2013

  • Wow, I used to work for Reliance Telephone Company in the late 1970's and 80's. We used to install and maintain its bigger brother the PAX 5100, which was the same kit, but in bigger grey metal cabinets.
    Nice to see it has been restored and is still working!
    .......... Colin Earl, Birmingham, 13th of September 2010

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