|PAX 222F Telephone Exchange|
|Made By||Siemens Brothers|
|Made In||London, England|
|Description||100 line Strowger PABX. Ex Croydon College.
The exchange can be dialled through the museum Asterisk server on Tel: 01239 350019 and asking the operator for "Croydon" plus a two digit number. Valid extensions include 18 and 11 (Wxchange Room)
|Conservation/ Maintenance History|
A number of damaged and badly adjusted line finders. After general maintenance the exchange appears to be in excellent condition and the first call was passed on the 17th of July, 2010.
Exchange required maintenance work which was carried out over two days by a volunteer with Siemens experience.
Bakelite spacers behind at least one thermal relay in the selectors had tracked and blown fuses. Thermal relays are being bypassed (provide long term off-hook protection).
General cleaning was required and a faulty rectifier identified, unit now powered from the main 227 PSU.
Work carried out by D. Williams
1) G relay in common control had no residual ? (now set to 5mil) ? caused linefinders to step slowly or fail to step