RK11-C indicator panel inlays?

Noel Chiappa jnc at mercury.lcs.mit.edu
Sun Dec 5 13:12:22 CST 2021

Let me get this out before the list gets shut down _again_...

There is discussion of doing a run of indicator panel inlays:


for the RK11-C (which is wired for an indicator panel, although as far as 
I know, DEC never did the inlay).

If you're interested... you will need a standard DEC indicator panel light
panel (with flat cables with plug-in-cards on the ends). (I don't have any
insight on how to get one of those. It shouldn't be _too_ hard to make
replicas, but I'll leave that topic for the moment.)

All I am proposing to do is create the silk-screened inlay that turns a DEC
indicator panel into an RK11-C indicator panel (starting with a functional
indicator penel without the inlay).

All DEC indicator panels use the same actual light panel and flat
cables/plug-in-cards (which have one conductor per light in the light panel);
which light comes on is set by the way the backplane slots the
cables/plug-in-cards plug into are wired.

So from the prints, which give the wiring to the indicator panel slots, I
managed to work out what an RK11-C panel would look like, roughly (captions
are made up, but the light locations are accurate):


Starting with that, Dave Bridgham managed to whip up a rough approcimation of
what the inlay would look like:


We had put a certain amount of work into identifying a font which looks like
the one DEC used, back when; I worked with a member the UK to produce a bunch
of blank inlays (right size/shape, with the black paint on the back with the
holes for the lights). Dave then found someone who could print the white
lettering on the front, and this is what the result looked like, on an
'RK11-F' (the QSIC with RK emulation microcode) panel:


You can compare with an original DEC inlay (TC08, IIRC) here:


That's on the same light panel, just the inlay is changed. (The lights in the
lower one are from the light panel Dave produced for use with the QSIC; it's
totally incompatible, electrically, with the DEC originals; 4 wires, IIRC, run
the whole thing (data, clock, latch and a ground), as opposed to the 'wire per
light' of the DEC originals. Looks _just_ like the originals (which Tech Sq
used to have a lot of, BITD), though.

Anyway, if anyone is interested, the next step would be to find out who all
wants an RK11-C inlay, and work out _exactly_ what would be printed on it.


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