[sebhc] H90

Mark Garlanger garlanger at gmail.com
Thu May 10 22:02:54 CDT 2007

Hi Carroll,

  I have a copy of the Operation/Service Manual for the WH89 that I
can let you borrow. Unfortunately, since I'm getting ready to move to
Austin for a new job, it has been packed away in a box. It may be a
while before I'll be able to send it. We still have to sell our house
and buy one in Austin. I also have a TON of spare hardware, so once I
do get settled in Austin, and depending on the issue, I may have a
replacement part I could send you.


On 5/10/07, Carroll Waddell <carrollwaddell at sc.rr.com> wrote:
> Does anyone have any troubleshooting experience on Heathkit H89? I
> bought 2 (neither will work) hoping to be able to repair and keep at
> least one.
> I've swapped the terminal logic board with the one in my H19 terminal,
> so I know the TLB is ok. The CPU board had several blown tantalum caps,
> and I've replaced those. All the voltages check out ok with little to no
> ac ripple. With a scope, I can see activity on the address and data
> lines but I still get no display on the CRT (except the blinking
> cursor). The TLB does give 1 beep when the power is turned on. (The same
> thing my H19 does)
> It's difficult to troubleshoot when the only thing visible is suppossed
> to be on the CRT screen.
> I suppose it could be in the serial port interface.
> Anyone else have any ideas?
> Carroll
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