22 Jul
2019
22 Jul
'19
4:51 a.m.
On Mon, Jul 22, 2019 at 5:21 AM ED SHARPE <couryhouse at aol.com> wrote:
Great to know Tony! Yea the battery is dead indeed! Will the wallwart power it
even though the battery is dead? Wish I could remember where I put the wall
warts... missing are the one for a 16 line portable, a disc drive and the thinkjet
printer.
I am pretty sure you need a good battery for the machine to work properly on the
wall-wart, although (unlike some older HP calculators) it will not be damged by
plugging in the wall-wart with a dead battery installed. I think it
sort-of powers up,
but I forget the details.
If you take the HP110 (16 line version) apart, you'll see that there's
a PCB the size of
the case with the CPU and RAM on it. Mostly RAM. Row after row of 6264's (8K*8
SRAM chips).
It's the same wall wart for both types of machine, for the disk drive
(either 9114A
or 9114B) and the HPIL Thinkjet. As for batteries, the disk drive again has
3 Cyclon cells (or a 6V lead acid 'block' battery) inside the battery pack, the
Thinkjet has 6 off Sub-C NiCds.
I have plenty of the wall-warts here, but of course the 240V model for the UK.
Oddly enough the HP 75 we have is missing its wall wart too! HP 75 also uses the
HIL i/o interface. will it know how to red the disc drive? I am missing HP 75
data and catalogs.... Ed#
It's the same wall-wart again!. The HP75 will run without a battery IIRC. That's
the 3 AA NiCd pack that goes right back to the HP35.
The HP75 will use the disk drive, but the disks are incompatible between the
drive used with the HP75 and the drive used with the HP110 (if you see what I
mean). I am sure clever software can get round it, as the hardware is clearly
capable of reading/writing both types of disk!
There are plenty of manuals, user, service, schematics, etc for all these
machines and peripherals over on
http://www.hpmuseum.net
Be warned there's a lot of fascinating stuff there for many HP computers and you
are likely to lose track of time :-)
-tony