Britain is Great (Back from the Island)

From: Hans Franke <Hans.Franke_at_mch20.sbs.de>
Date: Mon Sep 13 13:39:17 1999

> >> >(Well, the Old lady asked if three pounds may be to much ...)
> >> Cool find! Especially in the UK. I have five of them including two
> >> with consecutive serial numbers. I found four of them at one time at
> >> Patrick AFB.
> We have to keep your head from getting too big :-)
thank you

> >> What do you want to know about them? BTW I know the display
> >> was listed as an option but I think they ALL came with it. I've never heard
> >> of one that didn't have it.

> >Sounds logical - What I want ? EVERYTHING :)
> >AFAIK the 46 is just like the 45, but with Printer
> >and a 'real' keyboard.
>
> Yes but internally it is completely different from the 45. It uses
> mainly TTL chips instead of the hybrid CMOS ones that the 45 uses. It uses
> a *LOT* more ICs than the 45.

I just opened it (finaly - I could withstand for more than a week :),
and found a HUGE PCB (00046-66500 Rev C) with just 16 ICs and 5 spare.
Most of the chips are RCA, 5 are Mostek, and 2 are marked:
A*
MI

All but 3 parts have a numbering like 1820-0xxx, wher xxx is
939 14 Pin RCA 2x
946 14 Pin RCA 5x (Buffer ?)
848 16 Pin A*MI (Timing ?)
981 14 Pin RCA
993 16 Pin Mostek MK6036P (CPU ?)
994 40 Pin Mostek MK6037P (Decoder ?)

The Remaining 3 are numbered 1818 00yy where yy is
12 28 Pin A*MI (Keyboard Decode ?)
58 16 Pin Mostek MK6107P (RAM / ROM ?)
59 16 Pin Mostek MK6108P (RAM / ROM ?)
60 10 Pin Mostek MK6068P (RAM / ROM ?)(round package)

All A*MI and Mostek are Ceramic DIP, all RCAs are Plastic.

4 of the 5 spares are routed almost paralell to the
1818-0058/9, so maybe here is room for more ROM /
Microcode (Which would make the 58/9 ROM and the
1818-0060 the RAM - I just can' belive that HP had
already planned for 32 more RAM locations (each holding
a 10 decimal digit number), so this must be ROM).

The Keyboard is decoded via a 16 Pin DIL socket (Hey, did
_maybe_ one of the Apple ][ designers seen a HP 46 before :)


Oh, of course there are two more ICs on the display 'option'
(the machines still operates well without the display, so
this is realy an option) - which gives a total of 18 IC -
spread over an area of almost A3 size...

If I take of the ICs obviously used only for the Printer
(seven), and assume that in a different layout no printer
decoding is needed and the display is included, I may come
come down to 10 IC, all but one 16 pin (one will be 28,
for the keyboard), so the ICs should be prety much the same
as in a hand held calculator.
Received on Mon Sep 13 1999 - 13:39:17 BST