#strowger

[commodorez]

Strowger Step-by-Step telephone exchange. You could even play with it, it was fun. There's also parts of a crossbar type switch on the left, and a cord board on the right, showing the evolution of the technology

System Source Computer Museum

[commodorez]

(via https://www.youtube.com/watch?v=xZePwin92cI)

[forestpines]

Took the children out for a day of adventure, to London, to the Science Museum. I particularly liked showing them round the telephony displays and saying "Grandma/grandpa worked with this sort of thing." Here's some Strowger switches: a close-up of a small Strowger PABX; some sort of relatively early switch (can't remember the caption for that one) and a late (circa 1980) design of Strowger switch. Tagging @revertive-pulse because it's STROWGER!

[commodorez]

Normally I don’t post photo’s that aren’t my own, but I feel this illustrates a point very well.  What you’re looking at is a museum setup of a step-by-step telephone exchange.  These were probably taken from a small rural central office, and you can see it’s composed of Strowger mechanical switches. 

Note the rotary test sets on that shelf towards the left.  The orange one indicates that it’s designed for use in a central office, so the test clips are suited for that task (as opposed to field units which are typically blue).

[commodorez]

Strowger Step-by-Step Telephone Switch

This right here is the telephone switch that I’ve been trying to get my hands on for some time.  A Strowger SxS two-stage switch -- the first type of automatic switching equipment ever used for telephony.  The basic design dates back 125 years!

This here is a line finder module, designed to seek an empty line for a customer before they begin dialing.  As such, it contains 6 relays up top instead of 5 typically found on the intermediate selectors.  It also contains three levels of wipers instead of two.  This switch would require a bank of contacts in order to operate, which are kept separate for the purposes of modularity.

When in use, the center spindle would rise vertically, then spin clockwise and “cut in” to the bank of connectors, stopping when it found a vacant line to use.  After the call is completed, another relay would release the spindle, bringing the wipers back to a home position.

[commodorez]

Once again, I’m browsing ebay for more vintage telephone stuff that I don’t need.

At this rate I imagine that by 2020, I will have installed a crude step-by-step telephone network in my house for the lulz.

Damn you, Bell System belt buckle!  Your brass has seeped into my lead-stream and tainted my mind...  Well, time for some vintage phone trip tapes before I got to sleep.

http://www.evan-doorbell.com/production/

[paulstrowger]

(by Paul Strowger)

A quick self portrait after a productive day.

[paulstrowger]

(by Paul Strowger)

Bored, and feeling a little under the weather, so I thought I’d retouch a few old images.