One modification was made that removed the need for a routing digit if the call was for Ropley and not a tandem one. If seized via level 4 a NO relay would operate (Number Only),this caused the stored digits to be sent without a routing digit.
At Ropley level 3 from the incoming !st selectors gave direct access to the final selectors, the first stored digit on a Ropley local call being 3.
This facility later caused minor problems when several years later calls needed to be switched to the new exchange at Alton, the Alresford sets would send a routing digit of 6, at Ropley level 6 of the incoming first selectors was teed to level 3 of the local first selectors to give access to the Alton junctions.
The 0 and 1 sets at Alton and Medstead had the same feature on calls to Ropley.
Due to the limited number of junctions unanswered calls would be subject to a "time out" if the call was not answered within a specified period, the caller would get a short period of unobtainable tone before being force released, around 4 seconds. The timer used was the SU1 timer from a type 5 register.
In the early days, due to a lack of circuits between station, junctions were "bothway working" able to handle calls in either direction. The disadvantage of this arrangement was if the circuit went faulty (too frequently due to the overhead pole route) the equipment at either end had no means of knowing and the circuit would still be free for traffic and the call would fail. There were ideas for a junction guard arrangement on the bothway circuits but the idea was not developed.
Later, with the introduction of underground cables, most junctions became uni-directional and junction guard equipment fitted, if a fault developed the junction would be busied out of service and raise an alarm. Later a second route was provided between Alresford and Ropley for local calls between the two stations, this being the busiest telephone route on the system, the original route handling tandem traffic, if the local route became busy calls could overflow to the tandem route.
During a year 20 to 30,000 calls would be switched between exchanges, no count was made of own exchange calls.
Each exchange had a test number on XX99 giving multi line reversals and XX98 with a single line reversal on answer.
Ring back was provided on X8 and X0, the later was used as there were a few party lines in remote locations where line plant was scarce, these lines were always in the numbering range XX0X, the phones shared a pair of wires but the ringing was down one leg to earth depending on which half was called, the 0X code ring back gave reversed ringing to the 8X one.
One modification made was to reduce the apparent post dialling delay.
On the junction routes to the tandem unit pulse regenerators were used to store the number dialled, the junction relay sets would insert a routing digit before the stored number was sent introducing a further delay between finishing dialling and hearing a tone. When the final selector connected ring tone there could a 2 second delay in hearing the tone depending of the cadence, the modification connected a short burst of continuous ring tone when the final selector H relay operated then the normal ring tone would be heard, the ring tone would sound similar to a digital exchange.
Junction relay sets at Ropley, the sets in positions 3 and 4 were the incoming part of the Medstead linked number working. Relay set 10 was for a Printer Meter Check.
Two bothway circuits to Alresford, two bothway to Alton, two outgoing to Medstead and one spare set, originally a third circuit to Alton but traffic did not justify it.
A problem was noticed on calls through the tandem equipment; it was not practical having a person originating a call at one exchange and another in the tandem noting what was happening.
A modification was made to allow one to make an originating call from a distant exchange, a small relay set was connected to XX80 of the final selector multiple, connected to this relay set was a line circuit.
When XX80 was dialled from a remote site the relay set would seize the line circuit, additional digits could then be dialled via the final selector, the relay set counted digit trains, dialling a fifth digit would release the line circuit allowing another outgoing call to be made.
This allowed one person to make calls from one site while being at another to observe progress, using this system the fault previously mentioned was quickly found.
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