Phones


Posted on Feb 7, 2014

Working on strowger phone exchanges involves a lot of soldering, but unlike modern electronics, you can`t use a fancy temperature controlled soldering station, with built in solder stand etc when you`re up a ladder. For one thing, you`ve usually only got a 50V supply available and for another, there`s no where to put the base unit half way up a rack. So the irons we use aren`t temperature controlled, run off 50V,


Phones
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have electrically isolated tips (so you don`t accidentally earth things when you`re working on live circuits) and the soldering iron stands are connected to spring clamps so can easily be moved around the frame. The iron in the picture is showing its age somewhat (and having looked at the picture carefully, I notice there`s a split in the insulation that needs taking care of) but it does illustrate a tip I was recently given by a phone engineer. Always wrap a bit of solder around the cable of your iron, there`s nothing more frustrating than being up a ladder and realising your solder is in your toolbox or worse, on the bench at home. Having some emergency solder available within inches of the tip of your iron can save a lot of frustration. To celebrate that I`ve got enough tie lines working to phone from one side of the living room to the other, via the asterisk server at the Dean Forest Railway. I made a video of me dialling 30-0-50-91-491. Dialing 30 takes you out through an outgoing tie line and onto the junction selector, 0 takes you back into the 50/7A on an incoming tie line, 50 takes you out through another tieline and into my asterisk server. 91 are the access digits which take you in to the asterisk server at the Dean Forest Railway, 491 then takes you back into my asterisk server, which then dials 39 ³ on your behalf which takes you out *another* tie line into my 10/2A PAX and then it finally dials a 5 to ring...




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