21 Jul
2012
21 Jul
'12
10:49 p.m.
Hi Dwight,
Thanks for your suggestions.
I just opened up my H89 and there are a bunch of modules plugged into a backplane. The
backplane itself is labeled "mako data products MH89 plus 3". I guess it's a
third party module. Plugged into it were the following modules:
DISK I/O 85-2601-1
DOUBLE DENSITY 85-2597-1
This is a soft sectored board. I think the other is hard sectored. It sounds like
it was setup to use either. I'd have to check as my machines are in storeage
right now.
It sounds like an unusual machine.
Dwight
SERIAL/PARALLEL I/O BOARD
N.O.G.D.S HA-89-3-B
ATRA H-101-A with a H-201-B daughterboard
The last two seem like they have something to do with sound generation and the N.O.G.D.S.
board also has a video chip on it.
Beyond that, there are six toggle switches mounted between the main keyboard and the
numeric keypad and another toggle switch mounted on the floppy drive along with a second
LED.
Do you have any idea what any of this stuff is? In particular, do you know if the two
disk controller boards are for hard or soft sectored drives?
Thanks,
David
On Jul 22, 2012, at 12:51 AM, dwight elvey wrote:
From: dbetz at xlisper.com
It looks like I'm back in business collecting vintage computers. I went to the town
dump today and found what looks like an H89 but the model number tag on the back says
NN89-29. I haven't tried opening it up to see what's inside yet but it has a
floppy drive so I assume it isn't just a H19 terminal. Also, on the front it says
"Heathkit Computer". Even though I've had vintage computers before I've
never followed good procedures when trying to bring them up. Usually, I just plug in the
power cord and hope for the best. I'd like to do a little better this time. Can anyone
suggest an approach to bringing this beast to life that minimizes the chances that
I'll fry it the first time I power it on?
Thanks,
David
Hi David
We have a mail group that
is an active group that specializes in H8/H89s. It is a Googles group SEBHC.
One of the group members has our disk archives. Depnding on the format you need,
we have several different achive formats.
If you have hard sectored, determined by having a H27 controller ( might be
the wrong number ), I wrote a boot strap a number of years ago that can
get you started. It works through the serial ports and the PC end uses a DOS
program. One of the other fellows wrote a windows program for the PC
end.
The soft sectored card has a uP on it. One can create disk if you mount a
360K disk drive in your PC.
You can try to bring it up slow but I suggest disconnecting the video board.
It may still pop a tantalum or two. I recommend removing the cover so you
can spot the source of the smoke before shutting the power.
Also watch out for the unfused and unswitched line filter, that has been known
to blow ( don't leave it plugged in when not around ).
If you have a hard sectored disk, you'll need 10 sectored disk. I had a number
of manual punches made but sold out ( I still have a couple of the 16 sectored
punches if anyone else want one ).
One can still buy new disk at about $5 each. I use old 360K and my punch
to make what I need.
Diwght