Classic Rotary Phones Forum

Telephone Switching => Cross Bar Switching => Topic started by: ESalter on December 06, 2015, 10:35:35 PM

Title: 755A Crossbar PBX
Post by: ESalter on December 06, 2015, 10:35:35 PM
I took this photo earlier this year before our Open House at the museum.  On the right is our first strowger switch, a small demo that has 4 switches.  Key system and Merlin stuff on the back wall, and then the 755A in the middle.  It's by far my favorite of any of the switching equipment we have.  It has 4 trunks, 20 stations, and is capable of 3 links at a time.

---Eric
Title: Re: 755A Crossbar PBX
Post by: G-Man on December 06, 2015, 11:31:39 PM
Just picked-up four cabinets of a 757A but it's too big. I like yours better because it is easier to display.
Title: Re: 755A Crossbar PBX
Post by: AE_Collector on December 07, 2015, 01:32:40 AM
Boy, that's nice Eric.

I have an even smaller Crossbar demo unit but it is only an intercom. An Ericcson 636 PAX.

http://www.classicrotaryphones.com/forum/index.php?topic=15797.0

Terry
Title: Re: 755A Crossbar PBX
Post by: ESalter on December 15, 2015, 10:29:23 PM
Here is a video I took of the 755 the other day.  It isn't very good, but it's the best I have at the moment.

https://www.facebook.com/SSTelephoneMuseum/videos/487701178069360/

---Eric
Title: Re: 757A Crossbar PBX
Post by: Alex G. Bell on January 25, 2017, 01:21:41 PM
Just picked-up four cabinets of a 757A but it's too big. I like yours better because it is easier to display.
What features is your 757A equipped with?  For example, DID or station dial transfer? 

The minimum number of cabinets for a working 757A system is 3.  It may even be possible to get away with 2 by swapping slides around between cabinets but I have not studied doing that.

Also, while a 755A is conveniently compact, it's not really a PBX.  It's really a key telephone system.  Stations which require access to CO trunks must be key telephone sets.  Single line phones are limited to ICM service.  So a 757A is vastly more flexible and potentially useful in that it can serve ordinary single line phones.

What city and state are you located in?