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| Signal box telephones Medstead signal box. As well as a Norstar extension three signal boxes are fitted with working old style telephones, the dial phone cannot make outgoing calls as the Norstar exchange it is connected to does not accept a digit of 1. From the left - phone for box to box circuit - code phone, next is the phone for Medstead SPTs and then an auto phone. The first two phones have since changed positions, Although externally the phones are different the internal workings are the same and based on the circuit board from a late 700 series telephone. Some are fitted with bells, some buzzers and some with neither. In total there are now nine of these "heritage" phones in service.  Ropley signal box. Picture above taken early 2007 shows installation of telephones in the new signal box, against all advice old equipment was required. Since the picture was taken a Norstar phone has also been installed but has to be kept hidden from view. Signal box in service - spot the Norstar phone! It is there.  The latest old style phone to have new inners fitted. Was installed and working in Ropley signal box for a time but since recovered as some signalmen had problems reaching the microphone. Now located in the Ropley booking office as a display item, not working. Ancient and modern at Medstead. Code phones There were a number of wooden box phones used to give direct signal box to box service, these didn't work and the telecom department was asked to sort matters out. On the understanding the old system wouldn't be used each signal box had a small relay set using Post Office 3000 type relays, these relays formed a transmission bridge, controlled calling and sounding a call buzzer. There were a number of MF signalling Viscount telephones in store, being unsuitable for use on a Strowger system. The key pads were removed, this was the early days of MF phones and was done purely to make sure no one took the phone. These phones were used as the direct box to box phone, the entire system was built and installed in little over a week. Later several of the old wooden phones had the circuit boards of a Viscount phone installed with varying degrees of success, shown below is the one in Ropley signal box. 
During 2008 these phones were fitted with the circuit board from 700 series phones, this is now standard for all "heritage" phones on the railway. 
This is the latest variant using the components from a late model 700 type phone. It is a simpler design and makes any maintenance easier. For reasons forgotten in the mists of time SPTs became a responsibility of the telecoms department, there being no railway SPT equipment available new equipment was made using Post Office 3000 type relays. The original relay sets for the phones were built in multiples of 4 circuits and these are fitted at Alresford and Medstead, each having 8 lines installed. In the later installations at Ropley and Alton the relay sets have 5 circuits, giving a total of 10 lines. Alton and Alresford have ex UAX13 racks fitted in the exchanges for the SPT relay sets, lack of space at Ropley and Medstead exchanges meant the equipment is fitted in the signal boxes, here we have used cut down UAX13 racks, thanks to the railway Building Department for doing the metal work. Originally the Medstead equipment was in an external cabinet but suffered from relay coils going faulty despite having a heater installed. Medstead - old equipment in external cabinet. Original Medstead SPT equipment under test in the S and T workshop. Relay sets 1 and 2 - telephone line circuits, 4 per can 3 - common circuits 4 and 5 - main and standby ringers On the right are the electronic ring tone generator and connection strips. SPT in Medstead yard. Modified Bakelite phone fitted in Medstead signal box for local SPT circuits. The changes will not impress the purist. Alresford SPT concentrator and associated phone, it now has an approriate period handset cord. Thanks to the Telecoms department of the Festiniog Railway for donating the above 2 phones. SPT and miscellaneous equipment rack at Alresford. Alton has a requirement that when the box is closed the SPTs are diverted to Medstead signal box. The equipment that had been stored for this was removed from secure storage and dumped 6 miles away in the open, nobody had told us this was happening so by the time the items were discovered they were ruined. Being old technology it was not easy to replace it so a mixture of old and modern equipment has now been used. For a the time a direct circuit via the two Norstar exchanges was installed and tested should it be required to give the diversion service. As the circuit was in situ it has been made a direct line between the two signal box Norstar phones. Alresford, Ropley and Medstead use vibrator ringers but Alton has an electronic one. On two occassions Norstar switches have been used to give temporary SPT service, first at Alresford when the Strowger exchange was recovered and a new SPT rack was being installed. Second at Ropley, the relay sets from the old installation were required to be used during testing of the new system. Alton - showing the start of installation of the SPT rack also shown is the PP2040 The SPT rack at Alton with all the relays sets in position, a quick count shows there are around 130 relays plus some more at Medstead. Relay set at Alton to switch SPTs to Medstead, 10 circuits, relays used to switch lines to reduce wiring to selection keys in signal box. During the 2009 Spring steam gala the system was placed in service for testing, a phone acting as a SPT was installed in Alton signal box for these tests. The idea was to see if there were any unforseen problems. Several hundred calls were made during the three day event. Apart from a noisy cable pair, which there was not sufficient time to sort out, there were no problems experienced, thanks to the Traffic Department staff for giving the system intensive use, over 100 calls were made in 3 days Relay sets that are required to extend the SPT circuits from Alton to Medstead when Alton signal box is closed, 2 relay sets either end.
First and fourth sets for Alton and second and third sets for Medstead signal box Medstead - new equipment - bottom shelf has 2 spaces reserved for Alton circuits Concentrator at Medstead signal box where the circuits terminate when Alton box is closed. At the bottom of the wooden box are the keys for the Alton SPTs and the associated handset on the side. Modern equipment is being used as someone decided to throw out the older style keys, very thoughtful of them. Before building the parts for the Alton circuits a poll was conducted amongst the signalmen and the few who bothered to reply were happy with modern items. The top row of keys are for the Medstead SPTs. Medstead - new relay sets fitted - March 2009 Ropley (old box)- the SPT relay sets were located under the desk Ropley (new box)- replacement SPT equipment, it is now enclosed in a cupboard shown below. It will be noted on top of the cupboard is a Norstar phone, this is for emergency use for incoming calls from off site callers. When fitted it caused certain people to go into a state of apoplexy, there would have been less reaction if the box had been painted pink and covered in neon lights. It seems modern phones are a no no but modern 13 amp electrical fittings, just out of shot, are alright. After this item was added there was a view of Swanage signal box on the local TV news, in a very prominent position could be seen a Norstar phone, in no way hidden, they must be made of stronger stuff in Dorset. | |
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