crossbar switches...

[Eric Barbour]

At 12:18 PM 9/18/97 +1000, you wrote:

>were called crossbar switches and they certainly were big. They were in grey
>steel boxes not nice wooden boxes. 

Ah, the crossbar switch. It's a shame that they are so hard to find today--they
would be excellent for patching synthesizers. 

Until the 1990s, nearly every telephone exchange in North America used
hundreds of crossbar switch units. All dumped and replaced with ESS, then
digital, systems in the last 10 years. And I have NO idea what the Bell
companies and NT in Canada did with their old crossbars. Probably
melted them all down for their copper and silver content.

>I'm sure that they could be picked up 
>quite cheaply at some disposal outlet.

IF you see some (or, for that matter, Strowger step switches), let us know!

>It is quite likely that some more modern devices (these were designed in the 
>50's) were installed that used reed relays.

Reeds were used in later equipment--PBXs, mostly. Reeds were much more expensive
than crossbars for a long time.
Eric Barbour
Svetlana Electron Devices
Portola Valley CA USA