HP Forums

Full Version: Information please!
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
Any information about this

[Image: 00_zpsie2qj2xw.jpg]
Popular Electronics or Radio Electronics build this calculator type article maybe ??

It looks kinda familiar, the wires around the number switches in particular.

Any SWTPC logo on it anywhere ??
Maybe one of my instructors at sparky school (1981) had something similar on his desk ??
It looks like a kit from the 70's.
The cpu is a CALTEX CT5030 and the other two TTL ICs are driving the display.

A quick search shows a couple of articles where CALTEX name is referred.
Check it here for technical details.
The display looks like it was probably manufactured by National Semiconductor, NSAxxx series part, although I've never seen one with that sort of cylindrical convex filter.
(11-26-2015 09:56 PM)jebem Wrote: [ -> ]Check it here for technical details.

That was an interesting read. Thanks for sharing.

Quote:One good article series on BCD algorithms appeared in Electronic Design, volume 21 No. 13 through No. 19

It made me look for Electronic Design, Volume 21, Issues 14-20. Though it's possible to search in the book the results are somewhat limited. Sad
From the few glimpses I took it appears they handle the algorithms used in HP calculators.

Reference URL's