Serial Number ????
The 11/34 was a mid/late-70s implementation of the Unibus pdp-11 architecture, and was essentially a replacement for the 11/35 & 11/40. Along with the 11/04, it was the first pdp-11 to escape without a 'proper' lights & switches front panel, instead it had the glorified 'programmers console' as an option - a hex keypad and an LED display which showed address/data digitally.
It used a BA11 chassis identical to the full-size 11/04.
This rather disreputable-looking computer is one of my 11/34s - I've slightly lost count of these, I'm afraid - I picked up at least one, two I think, from the Mersey Tunnel, where they had been used to run the tollbooths. I'm certain I 'recycled' at least one of them to a more deserving cause which also needed a BA11 box - pdp-15 memory expansion box, or a BA11 for the Unibus bits in one of my DECSYSTEM 2020s. I've got at least one left, this is it.
I don't especially like 11/34s... effective, useful, but dull. Not enough lights.