Calculator Comparisons - test-drb@ccmp.vtda.org

23 Oct 1999

...
 Wow!  Thanks for the link.  I happen to have a nixie
tube strip that looks
just like the one in the AL-1000.  The one I have has 12 CD71 tubes (plus
the minus bulb).  On the bottom, there are characters in English and Katakana.
Some of the part numbers are "IS-1", "Model 121" and
"I2D-E2(B)".  The
Katakana appear to be representative of digits.

I've always wanted to do something with this (like so much of my really good
stuff,  I've had it since I was a kid).  I've just noticed that 12 digits
is enough to make an ISO Date compatible clock/calendar (i.e., 199910220116).
Is there a good reference around about how to drive a multiplexed neon array
going from TTL to 90VAC? 
Can you multiplex a Nixie display in the same way as a LED display?  I've
never seen it done, but that certainly doesn't mean it isn't possible.

If you don't mind direct drive, there are TTL BCD-to-10 decoder chips
intended specifically for driving Nixie tubes.  I just looked in my
newer databook at the 7445 and 74145, and they don't *say* "can directly
drive Nixies", but they do have high-voltage open-collector outputs.
They look more like open-collector lamp drivers than Nixie drivers
to my eye this morning.

I swear there were TTL chips which could directly drive (err, well, sink)
Nixie displays, but they aren't specifically called out in the newer
databooks.  I've gotta find the box that has Don Lancasters _TTL Cookbook_,
I know there's an example in there.

-- 
 Tim Shoppa                        Email: shoppa(a)trailing-edge.com
 Trailing Edge Technology          WWW:   http://www.trailing-edge.com/
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