phone systems, old and less-old

[Fred Cisin]

On Wed, 18 Sep 2019, Jon Elson via cctalk wrote:
> Oh, my Gosh!  the first 3 pics are of a KTU phone system.  If you are OLD 
> enough, remember the phones with 5 line select buttons and a red hold button 
> below the rotary dial?  That is what that unit supports, the 565 phone.

Please don't let anybody call the 25 pair 50-pin miniature ribbon 
connector (RJ21),  "Centronics"!