25 Aug
2016
25 Aug
'16
10:52 a.m.
-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Ethan
Dicks
Sent: 25 August 2016 18:12
To: rob at jarratt.me.uk; General Discussion: On-Topic and Off-Topic Posts
<cctalk at classiccmp.org>
Subject: Re: MicroVAX II Console Garbling Characters
On Thu, Aug 25, 2016 at 1:05 PM, Rob Jarratt <robert.jarratt at ntlworld.com>
wrote:
Unfortunately I spoke too soon. When I tested it again a bit more extensively, it suddenly
stopped working. I am going to have to solder in some wires to pins 2 and 3 and see if
that helps.
Regards
Rob
Just a bit more info on this.
I tried cleaning up the corrosion, and that briefly seemed to make a
difference, but then I realised the problem persisted. I looked again
and realised that the corrosion around the DE-9 pins was a bit bad.
Initially I thought to solder some jumper wires around pins 2 and 3,
but when the solder would not melt very easily, I found that it kind
of flaked off under a bit of heat and physical pressure. This made me
think that although I was getting continuity with my DMM, the joint
was not that good. So I desoldered the whole DE-9 connector, cleaned
the board with PCB cleaner and then resoldered it back.
This seems to have fixed it.
My own cab kit was also exhibiting gray solder that did not flow, so without
even testing it, I presumed it was faulty and I removed the
DE-9 and cleaned the PCB. That's as far as I've gotten this week. I still plan
to
test the resistance of the traces because, sometimes, those are consumed or
heavily damaged (I've been reading a lot of Amiga Varta repair threads lately
- that's another platform I'm cleaning damage on). The question I have for
the MicroVAX is if I trust the integrity of the DE-9 itself. I can solder in a fresh
replacement, but I _think_ the old one is probably still good.