Hello All, not only did we see the new Pacific 60500 Edward Thompson , but we also saw what at the time was the largest area controlled by one signal box in the UK, the 1948 York Panel. As was demonstrated , this used Unilever or Individual Function Switches / IFS ( as they were later called ) to control the signals or points. Compared to later practice each switch was engraved with its number , and the switches were grouped into logical geographic sets. Later on , the object number was engraved below the switch , so if a switch needed replacing ,you did not need to pre-engrave it before installation. The particular switch design illustrated remained in production until the early 1980s , so, especially by todays standard, they had a long operational life. If I recall correctly , the 1948 York Panel eliminated 10 signal boxes and eventually led to the closure of a number of yards and holding loops due to significantly improved traffic throughput so it was a significant investment which demonstrated the potential savings consolidated Power Boxes could deliver. The LNER was actually quite progressive and innovative in Power Signal Box designs , Thirsk, 1938 for instance was the first main line route setting panel , Doncaster , 1949 , used rotary switches for route selection ( but not a true route set panel as such ) , and the BR ER Fenchurch GE Lines 1500 VDC Electrification scheme used CTC/Centralized Traffic Control for remote interlockings that used telephone switching for control. ( General Railway Signal / GRS first used telephone cross bar exchange equipment for CTC in 1940 on the Atlantic Cast Line , this meant that ordinary telephone wiring could be used to dial up a location , and by throwing a switch on a Signal Control Panel, standardised sequential numbering of a location and an object , could be activated. This saved an enormous amount of wiring, as each set of objects eg a point and a signal for a particular direction, was effectively one telephone number. Interlocking through the CTC machine was controlled by the cross bar exchange where only the dialled number was activated, and as each cross bar machine could only dial one number , therefore the other potential numbers were isolated and could not be dialled. ) Good choice , Paul , thoroughly enjoyed it. Best wishes and regards, Echidna
I live British transport films My favourite is "under night streets" and "all that mighty heart" Another of note was "single line working" Cameron
