What is OBA11-VA?

Tony Duell ard at p850ug1.demon.co.uk
Sun Jul 18 14:31:37 CDT 2010

> I ran across a DEC OBA11-VA (attached to a dual TU58 drive) while sorting 
> my junk room. Anyone have a link to documentation or any information on it?

A BA11-V is a small Qbus mounting box, the same size as a TU58. IIRC it 
contains 4 dual-height Q-bus slots (probably Q18 only) and a PSU. 

The auffix 'A' may mean it's set for 115V mains. I have no idea what the 
prefix 'O' means

I beleive some model of TU58 didn't have an internal PSU, rather it took 
power from the PSU of a BA11-V that it was bolted to. May be worth checking.

What (if anything) is in the Qbus slots of the BA11-V?

[As an aside, the BA11-V was not uncommon in the UK as the housing for 
what was known as a 'York Box'. This was a unit to connect standard-ish 
hosts (PERQs and VAXen mostly I think) to the then-current X25 network. 
The BA11-V contains an SBC21 ('Falcon') CPU card, a RAM card (32Kw, I 
forget the model number, but it's the standard one), a DPV11 (sync serial 
port to connect to the X25 line) and a DR11 (parallel interface). The 
host was conenected either to the DRV11 (using, perhaps a DR11 in a VAX) 
or to one of the RS232 ports (async) on the SBC21)]


More information about the cctalk mailing list