what where R141 flip chips used in?

[rorypoole]

what where R141 flip chips used in?

 

[rorypoole]

I have found a DEC backplane, its labbled that it is for a pdp8? but my flip chip map has no R141 flip chips in it? it has about 80 flip chips in in

 

[vrs42]

what where R141 flip chips used in?

I know they are used in the LINC-8 and in the TC01.

I don't believe they are used in the straight-8 itself, the 8/S, or the PT08.

I don't know about non-PDP8 gear or other peripherals.

Vince

 

[tradde]

I have found a DEC backplane, its labbled that it is for a pdp8? but my flip chip map has no R141 flip chips in it? it has about 80 flip chips in in

Is that from the sliver tag on it? Does it have any other info or numbers on it? It should have what
type of backplane this was.

 

[rorypoole]

Its made up of two 1943 Mounting panels for a standard 19-inch rack with 88 flip chip modules, and marginal check switches, but its listed as a pdp8 so maybe it could be part of a LINK-8?

 

[vrs42]

Its made up of two 1943 Mounting panels for a standard 19-inch rack with 88 flip chip modules, and marginal check switches, but its listed as a pdp8 so maybe it could be part of a LINK-8?

I don't think it is part of a LINC-8.

I think what you've got there is two of the same thing, bolted together. Each backplane segment has the same cards in the same order, and very similar wiring on the back. Now, what they are, I don't know. There are 20 R141 in the top row, which is a heck of a lot of AND-NOR, and also 7 inverters. In the bottom row there are 8 bits of Schmitt trigger, 8 bits of latch, 20 2-input gates, a binary to octal decoder, 9 more paired 2-input gates (maybe 8 were used?), 7 bits of general purpose gate extension, 8 bits of relay driver. There is also an illegible module on the left of each row.

I'm guessing each backplane has some kind of 8-bit input-output device similar to a parallel port. but what the 20 bits of mux and gating is for I have no idea.

Hope that helps!

Vince

 

[rorypoole]

thanks that is a big help Vince

 

[rorypoole]

would it be a crime to take the unknown backplane apart, to build part of a straight 8?

 

[vrs42]

would it be a crime to take the unknown backplane apart, to build part of a straight 8?

I think it might be a shame, if these turned out to be some rare inter-processor option between an 18 bit machine and the PDP-8, for instance. I'd like to know more about them before I took them apart -- ideally, have at least a schematic to work from in case someone wanted to re-create one someday. Otherwise you could end up destroying the last place that information still existed.

I see unwrapped backplane on eBay from time to time. Heck, I might even be willing to trade you an equivalent amount of it for your wrapped backplane. (Of course, the shipping would be the killer there.)

Vince