13 Oct
2016
13 Oct
'16
12:56 p.m.
On 2016-Oct-13, at 10:39 AM, Jim Brain wrote:
I thought the question about the prevalence of
.156" connectors in early systems was interesting and I assume someone here has the
detail on the rationale.
Jim
-------- Forwarded Message --------
Subject: CBM edge connectors pitch?
Date: Thu, 13 Oct 2016 19:31:47 +0200
From: silverdr at wfmh.org.pl
Reply-To: cbm-hackers at musoftware.de
To: cbm-hackers at musoftware.de
Do we know what is the norm used in the CBM edge connectors? Like the IEEE, USER PORT or
CASSETTE?
I found out mentions that it uses a 0.156" pitch. Where the heck does that come
from? Nothing "round" in either metric or imperial..
--
SD!
Message was sent through the cbm-hackers mailing list
The 0.156" is presumably the oldest PCB edge connector, I have an example in tube
equipment going back to 1959.
Very common in all sorts of equipment through the 60s and 70s.
As Tony suggests, it matches up with 5/32" spacing, just as 0.125 is 1/8".
Where the rounding of the 1/4 thou (0.00025) took place - in the name or the
implementation - I'm not sure.