Wes Groleau wrote:
Sorry for being off-topic, but the heath/zenith NG seems to have died.
Does it help if I have an expired ham license? :-)

I have need of an RS-232 terminal, and I know that
my H89 (with no floppy--boat anchor!) contains one.

Can anyone point me to details for disconnecting the
H19 board from the CPU board and connecting it instead
to the DB-25 on the back?

This is from vague, 27-year-old recollection.
There are two boards in the H89. One of the boards
is the computer, the other is a terminal. The terminal
board is the one attached to the actual CRT, the computer
is attached to the (100KB, hard-sectored) diskette drive.

The computer and terminal are attached with a single
cable with perhaps 5-7 lines using standard RS-232
levels. You just need to pull that cable off, figure
out the pinning on it, and make a replacement cable to
connect to the DB-25. I can't remember well, and I advise
proceeding with caution, but I very vaguely recall that
maybe you could move the cable that connects the computer
to the DB-25 to the terminal board, after removing the
cable that connects the two boards together.

(Even better, connecting it directly to a DB-9 which I'd have to buy)

I need it to configure a Sun Ultra, since I don't have a Sun monitor.

You've got some vintage hardware there ;-)

Dana K6JQ

Dana Myers wrote:
maybe you could move the cable that connects the computer
to the DB-25 to the terminal board, after removing the
cable that connects the two boards together.

Hmmm. That's probably correct! In fact, if I recall correctly,
there are both DCE and DTE connectors on the back.

Thanks, I will definitely look into that!

You've got some vintage hardware there ;-)

Just call me cheap. The vast majority of the computers
I've had cost less than fifty dollars each.

--
Wes Groleau

Measure with a micrometer, mark with chalk, and cut with an axe.