Previous message: Wire list for the RKV11-D Qbus RK05 controller backplane anywhere?

Chris Zach cz at
Wed Feb 12 18:40:45 CST 2020

On a related note, what kind of documentation is out there for the 
various oddball QBus to Unibus converters? I have at least two of the 
Plessy models that came from the USPS project in the 80's (they used 
pdp11/23 cpus in a Q bus backplane next to a Unibus backplane that had 
all the X.25 comm cards) but I haven't had a need to use them. I think 
they were at least 18 bit cards.

What else was there?

On 2/12/2020 12:28 PM, Noel Chiappa via cctalk wrote:
>      > From: Jay Jaeger
>      > Yeah, info does seem to be scarce.  Not even in my LEVAX fiche set.
> My fiche set has the Technical Manual, and also (in the wirelist
> section) the wirelist.
> Not sure how to get it to you, though. I stuck it in my industrial-grade
> scanner at its highest resolution; no go. I suppose I could take photos
> of it displayed on my fiche reader?
> Or is there some device I can buy which is less than a zillion dollars which
> can scan fiche? There are a number of things in my set (e.g. the BA11-N Tech
> Manual) which aren't online, and would be useful to have.
>      > That fourth card (M7268) is apparently a connector card for the Q-Bus
>      > and drive bus.
> Yes, but actually there are 6 cards: the M7269 is a dual card which goes
> into the QBUS backplane, and the M993-YA which goes into the first RK05,
> to convert from the two flat cables which come from the M7268.
>      > From: Al Kossow
>      > Also, it is only 18 bits.
> Actually, only 16-bit DMA addresses, I'm pretty sure.
> 	Noel

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