22 Mar
2012
22 Mar
'12
8:06 a.m.
On 03/21/2012 10:03 PM, Tony Duell wrote:
No,m the one I was thinking of, and I am pretty sure it was on a CDC unit
-- perhaps a Phoenix drive -- has the same size as an RL unit select cap.
But it was opaque black plastic and obviosuly didn't have a lamp behind
it. The coding was done in the same wway wit hthe edges of the 2 sid
tabes. Whether it was the same code I don't know.
Oh! Yes, that's totally different. I don't think I've ever seen
that one, at least not that I recall.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
IIRC there are 2 pins at the sides, it's the top
and bottm edges of those
that matter. Each edge can eiterh be straight out cut in a bit, they
operate 4 contacts i nthe lamphoder. One always operates when the cap is
fitted (this inidcates a cap _is_ fitted, removign the cap disables the
drive). the other 3 edges encode a 3 bit (yes, I do mean _3_ binary
number). In the RL's, only the bottom 2 bits are used, the RK06/RK07 use
all 3 bits (and ahve caps numbered from 0-7), I think some CDC drives
used a simlar system, but the cape was opaque and didn't also act as the
'ready' lamp.
I've seen this on many CDC drives. It's a small white plug, perhaps
1/4 the size of the DEC RL0[12]/RK07 unit select plug or a bit larger.
Its plug end is shaped like a '+', and that's cut out in various ways to
actuate the contacts in the socket.