21 Feb
2009
21 Feb
'09
11:16 a.m.
-----Original Message-----
From: cctalk-bounces at classiccmp.org [mailto:cctalk-
bounces at classiccmp.org] On Behalf Of Robert Jarratt
Sent: 20 February 2009 22:45
To: cctalk at classiccmp.org
Subject: Powering up a 20-year old MicroVAX II
I have just collected a MicroVAX II which has been in storage and has
not
been powered on for 20 years. This is my first machine of such an age,
unfortunately I am not particularly knowledgeable at the electronics
level
(I studied circuits academically 25+ years ago and can solder a bit,
but
that is as far as it goes). I know I will need to treat it carefully in
order to get it working again. I plan to open it up and make sure I
clear
out any debris etc, but beyond that I need advice from those with the
experience and knowledge that I lack on how to go about powering it up
carefully.
Thanks
Rob
After removing all the boards and leaving just the disk and tape drive for
load I impetuously decided to try powering it up. I knew the PSU (model
H7864) was set for 110V and made the switch to 240V (I am in the UK). When I
connected the power cord, after a few moments there was a loud pop, followed
by another before I could pull out the power cord, smoke rose from the PSU.
This sounded just like when I had once accidentally made a 110/240 mix-up.
The question is, could it be that I had not made the switch to 240
correctly, or could this just be down to the age of the PSU?
Regards
Rob