Start with the power supply, obviously. If you have no fan, that has to be the problem. It’s an old-fashioned analog supply, so should be easy to troubleshoot if you have the schematics.
From: sebhc-bounces@sebhc.org [mailto:sebhc-bounces@sebhc.org] On Behalf Of Mike Shields
Sent: Tuesday, March 20, 2007 1:07 AM
To: sebhc@sebhc.org
Subject: [sebhc] Reviving an H89
Hello everyone,
A brief introduction - I'm probably a little younger than most of the group, but I started my career as a programmer (at 4 years old in BASIC) on the H89 that my father assembled. I grew up reading REMark and Sextant and helped to build and upgrade an H-150 along the way.
Well, I recently took possession of the H89, did a quick interior dusting and exterior cleaning, and attempted to power it on. But, powering it on does nothing. No fan, no clicks, no smoke, nothing at all. The fuse is fine. I did a quick visual inspection of the power supply (without removing anything) but didn't see anything amiss, and there's no scent of smoke. I was the last one to use the machine, but I don't remember having any problems with it. (Although, that was 15-20 years ago, memory isn't perfect)
Just looking for suggestions as to common failure modes that would result in st
one-dead behavior. I have some spare H89 parts that I'd like to upgrade it with, but I've got to get it firing up first - I've got meters, scopes, and experience with them, so any suggestions at all are welcome. I do have the schematics and manuals for it, so pointers to those are fine too.
Thanks, and long live Heath!
Mike Shields