This collection of 30 card-mounted pictures was passed onto me by Bob Freshwater as rescued from GEC's factory before demolition. They were evidently intended to be shown to prospective customers as examples of previous contracts, showing what was possible. As can be seen from the view of the originals below, the photos had faded considerably. By adjusting the black and white thresholds and tweaking the gamma in greyscale I've been able to restore the images to more like original condition.
Click on a picture to open the gallery view for a larger picture. Use right and left arrows to move forward and backward through the gallery. Either press Esc or click on Close to return.
Pictures 1 and 2: 'Part of CB PBX, GE Co London'. For modestly sized switchboards it was obviously economical of space to incorporate the distribution frame into the body of the switchboard itself. The back reveals provision for 100 extensions. Below are the 20 cans for the cord circuit relays.
Picture 3: 'CB Visual Signal PBX'. A reference to the circular holes at the top containing a flag that rotates when an extension was off-hook to show a solid disc.
Picture 4: '50-line Magneto Switchboard'. This uses flaps which drop down when a ring signal is received. The operator needs to push them back when clearing a call. The rectangular shape is an early design. Later ones are square.
Pictures 5 and 6: 'PBX for Australian Govt'. The sign announces the provision of ten extensions, three exchange lines and six cord circuits. There are thirteen call indicators and thirteen jacks, but no marking as to which are extensions and which exchange lines.
Pictures 7 and 8: Two more marked 'PBX for Australian Govt'. The smallest on offer is the tiny 1+3 alongside its big brother the 2+5.
Pictures 9 and 10: Marked '200-lne CB PBX with mainframe cabinet as supplied to Indina Government'. The other picture is the power distribution board for the same switchboard.
Pictures 11 and 12: Marked '30 line magneto switchboard, combined drops & jacks with mechanical restored drops'. The drop indicators on this board are square suggesting a later date, nearer 1920. The five exchange line drops are at the top. Curiously there are six keys below them that may be speak/ ring keys, but there are ony five cord circuits.
Pictures 13 and 14 : Marked '50 line magneto switchboard, with main frame cabinet'.
Pictures 15 and 16 : Marked 'Sales Order 4839 30 line magneto switchboard'. Extensions 18 and 24 are calling and Extensions 1 and 15 are shown plugged together.
Pictures 17 and 18: Marked '200 line CB Switchboard for North British Loco Works'
Pictures 19 and 20: Marked 'Westminster Palace Hotel PBX 200 Lines'
Pictures 21 and 22: Marked 'Order No 19602 North British Railways 100 Line CB Board' Two not quite identical boards. Notice the separate speaking set with calling keys along with a voltmeter. It's on the end of the first board and on the face for the distribution frame part of the second. Its purpose is not obvious.
Pictures 23 and 24 below: The second switchboard with its keyshelf opened to show the wiring and the back view revealing the relays and cord circuits.
Picture 25: Marked '100 Line CB Switchboard (lamp signalling) with arrester cabinet for Domodosola Italy'
Picture 26: Desk type of 100 line CB PBX
Pictures 27 and 28: Marked '200-line magneto switchboard, tropical pattern, for Indian Government' Notice that it only has 110 jacks.
Pictures 29 and 30: Marked '30 line CB switchboard for North British Loco Works'
Other pictures Index