HP nixie tube module information needed

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Tue May 20 19:29:58 2003

> Hello,
>
> Probably my best find at the recent Hamvention in Dayton OH was a
> stack of nixie tube modules made by HP. In retrospect, I wish that
> I had purchased the whole box of them, but I hopefully have enough
> to at least make a clock.
>
> I have two variations on the modules, the part numbers are:
> HP 05212-6016 series 648
> HP 05212-6003 series 415

I have a schematic for the 5212L-4A Series 401 counter which might be
closely related

> They both use Borroughs B422 nixie tubes and look like they may have
> an integrated HV supply of some sort.

No. The black plasic block is a latch and decimal decoder (!). It
contains 8 neons (look like NE2s, but the parts list doesn't give
individual parts for this block) which perform the latching function for
the 4 bits and their inverses. The top of the block is a thick film
circuit of LDRs which forms a decoder tree to turn on the apporpriate
cathode of the nixie tube.

I can provide a pinout of the 15 pin card edge, but the signals may not
be too obvious without the complete service manual. Pin 1 is towards the
front (nixie tube) end
1 : -130V
2 :
3 :
4 : +170V
5 : Transfer Input (latch enable)
6 : BCD Output A
7 : Signal Input
8 : Gate Input (Not used?)
9 : BCD Output B
10 : Signal Output to next decade
11 : +20V
12 : Reset Input
13 : BCD Output C
14 : BCD Output D
15 : -15V


> I would appreciate if anyone can tell me what HP (or other) instruments
> may have used these modules. I would also like to find a schematic of

Well, the 5245 Counter uses closely related modules (I have one of these
instruments and the full service manual...) Doubtless other instruments
did too...

-tony
Received on Tue May 20 2003 - 19:29:58 BST