Tuesday, September 10, 2013


Image credit - ebay

From issue #2 of Byte Magazine - 1975

Friday, July 19, 2013

FYI, from Mike Willegal / Newsgroup posting

I thought this was fairly important so wanted to share this here --  From Mike Willegal (willegal.net)


FYI,


Amphenol 78S4 sockets and 86CP4 plugs were the "standard" connector used for connecting the power supply to the chassis and peripherals on the SCELBI. Current supply is limited and prices are rising. Corey tells me that Leeds Radio in New York told him that the sockets went out of production last year. The socket can be currently found at a alliedelec.com and the plug can be found at tedss.com (tedss also has a ebay store). Cost is approximately $9.00 each. Last year the sockets were under $5 and I saw an ad from the 70's where the similar 78S11 sockets were twenty five cents each.


Note that unlike the I/O ports, the plug is situated on the chassis and socket is on the end of the cable. This is to prevent someone from inadvertently touching live power to something that shouldn't see live power. They used grey clad multi-conductor cable. I think that similar grey clad cable is still available from standard sources like mouser or digikey.


Note that some original SCELBI owners integrated their power supplies directly into the chassis, removing the need for an external box and cabling. 


A picture of what I think is a production power supply is on the CHM web site. I'm guessing that SCELBI built some standard or modified Power-One supplies into this power supply chassis, but so far, my efforts to get that confirmed by the CHM or SCELBI employees have not been successful. 


http://www.computerhistory.org/collections/accession/X714.86A


Someday I'd like to reproduce it.


regards,

Mike W.

Sunday, May 19, 2013

Chassis.
These are just a few pics of the backplane taped into place in the chassis.
I hope I have it right -- ;D

(Thanks Corey!)