Mystery HP 1000 board

[CuriousMarc]

Ah, thanks, this is getting awfully close, and jives well with Jay's recollection. Low frequency spectrum analysis using FFT seems to be the application indeed. Mentions an "arithmetic booster board" bolted to the bottom of an HP 21MX K (whatever a K-model is, never heard of it, but seems to be made of an HP 2105 model, I'll look that up) to improve FFT performance. They call the combo a "5443A" processor. That's dangerously similar to my 54427 board numbering and "booster" naming and fits right in with the 74S181 bit slice 20-bit ALU. I haven't found the particular system that would use an E-series computer, but I'll keep looking in this direction. 
Marc

-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Paul Birkel
Sent: Wednesday, June 15, 2016 10:44 PM
To: 'General Discussion: On-Topic and Off-Topic Posts'
Subject: RE: Mystery HP 1000 board

See: http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1977-10.pdf  Figure 4  

Shows some of those other parts as well in the block diagram.  Uses a "HP 21MX K-Series Computer".

Model 5420A Digital Signal Analyzer.

-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of CuriousMarc
Sent: Thursday, June 16, 2016 1:16 AM
To: 'General Discussion: On-Topic and Off-Topic Posts'
Subject: RE: Mystery HP 1000 board

You beat me! You got one hit. How did you search for that? I come up dry...
Marc

-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Pete Lancashire
Sent: Wednesday, June 15, 2016 8:50 PM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Mystery HP 1000 board

Well there are 20 bits of ALU ....

And this guy has one and some other boards

http://nevadabarry.com/electron.html#HP%20Test%20Equipment

  HP 5443
  05443-60047
  05443-60042
  05443-60031  MIOB Interface
  05443-60050 Booster Microcode
  05443-60057 C (13803F?)
  05443-60071 A (22803F)

NO Connection with the site/person/etc .. just passing it on

On Wed, Jun 15, 2016 at 8:00 PM, Jay West <jwest at classiccmp.org> wrote:

> I have one of those boards. You sent me an email about it and I 
> replied a week ago :)
>
> -----Original Message-----
> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of 
> CuriousMarc
> Sent: Wednesday, June 15, 2016 9:49 PM
> To: cctalk at classiccmp.org
> Subject: Mystery HP 1000 board
>
> Can anyone identify this HP board (see link to pictures)?
>
> https://goo.gl/photos/BBuAV1oozWNSqeUTA
>
> It was at under the main board of a newly acquired HP 1000-E, next to 
> the firmware board. It says HP 54427-60050 Booster Microcode. It has 5 
> bitslice SN 74S181 chips at the back. So I surmise maybe it's a late 
> ALU booster upgrade?
>
>
>
> Marc
>
>
>
>
>
>