[cctalk] Re: How were 32-bit minis built in the 70s/80?
Interesting note. Back in the 80's a company called Northern Telecom used 2900 ALU chips to run the SL-1 PBX. It was very popular in hospitals and large firms where down time was bad. It had redundant memory and processor cards for failover. And battery backup to stay up during a power failure. Certain alarms caused the switch to dial a reporting center and send the alarm. Programs were stored on a 3M cartridge tape (6150?) where diagnostic programs ran off hours and communication was accomplished via a 300 baud dialup modem and a local hard copy terminal (usually like a DEC LA36). Call detail records were stored on a 9 track tape. -Ken On Fri, Oct 6, 2023, 8:33 AM Geert Rolf via cctalk wrote: > Quote: > > > I could be remembering incorrectly but I think the Gould PN6080 mini we > had exclusively for third year > > comp sci at Macquarie Uni in the mid/late 80s was 32-bit made up of > AMD2900 family logic (2901 ALU's). > Find attached two pages of the CPU drawings of a Concept 32/67 and > PowerNode 6000. Here the AMD 2901s show up. You remembered correctly! > > Geert Rolf > > owner of a PowerNode 6040 -- see > https://geerol.home.xs4all.nl/DownLoad/UTX-paper.pdf > >
[cctalk] Re: How were 32-bit minis built in the 70s/80?
Quote: I could be remembering incorrectly but I think the Gould PN6080 mini we had exclusively for third year comp sci at Macquarie Uni in the mid/late 80s was 32-bit made up of AMD2900 family logic (2901 ALU's). Find attached two pages of the CPU drawings of a Concept 32/67 and PowerNode 6000. Here the AMD 2901s show up. You remembered correctly! Geert Rolf owner of a PowerNode 6040 -- see https://geerol.home.xs4all.nl/DownLoad/UTX-paper.pdf
[cctalk] Re: Obsolete Parts.... Unicorn Electronics
On 06.10.2023 03:10, D. Resor via cctalk wrote: I recently had a need for BC308 transistors. Of course those have been unobtanium for quite some time. My search beyond a distributor then went to eBay where I found Unicorn Electronics. More to the point I see from their website Apple 1, Apple ][ and Apple 1a Kits along with Apple 1 and Apple II parts are available. I thought some here might find this useful. https://unicornelectronics.com/ Don, unicorn is known for long for interesting old semiconductors. I have also ordered several parts from there, even from Europe which result in rather high shipping and tax costs. Whether the Apple kits are a good deal though, I have my doubts. The BC308 is the PNP complementary part to the former NPN work horse BC238. Both are nowadays difficult to find. However, as they were rather universal types, you can usually replace them with BC548 (NPN) and BC558 (PNP) today without problems. Holger
