Welcome, Guest. Please login or register.

Author Topic: Intermittent A1200 problems caused by PSU?  (Read 1663 times)

Description:

0 Members and 1 Guest are viewing this topic.

Offline Abou27Topic starter

  • Sr. Member
  • ****
  • Join Date: Oct 2003
  • Posts: 306
    • Show only replies by Abou27
    • http://www.renault-agriculture.co.uk/forums/
Intermittent A1200 problems caused by PSU?
« on: February 16, 2004, 08:39:19 PM »
Hi folks.  I've been having many interesting and intermittent problems with my A1200 (030 50/50 128MB) over the last few days.  For a couple of days a flash of 'interference' would appear briefly on my Microvitec 1438 monitor.  Didn't think much of it - checked leads etc and all fine.  Thought was getting a burning smell from power lead entry point on computer, so opened and removed shield but could see nothing amiss.  Left computer running for a few hours, came back and wasn't aware of any smell.  Then, I was standing some way from computer and it powered down and straight back up again.  Anyway, things seemed back to normal.  Using last night, however, the monitor picture suddenly went very pin-cushiony and stayed like that.  Curiously, making contact with the horiz adj button temporarily restored normal display.  Switched monitor off, waited a while, then back on - no problem.  Finished with computer and switched it off (monitor still on).  Nudged PSU (A500 one) and the monitor flashed to a lighter screen.  This was with Amiga off.  I switched all off and removed PSU.  My question is: do you think this is what is likely to be causing problems?  I got the PSU second hand and don't remember what they were originally like.  It seems to run very hot - can hold hand on but is uncomfortable - and is very lightweight compared to the A1200 stock PSU.  Is this due to capacitors or what? (Apologies if this is an amusingly ignorant question) Should it be this lightweight?

Cheers.
 

Offline SilvrDrgn

  • Hero Member
  • *****
  • Join Date: Feb 2002
  • Posts: 1215
  • Country: 00
    • Show only replies by SilvrDrgn
    • http://mikerye.ddns.net
Re: Intermittent A1200 problems caused by PSU?
« Reply #1 on: February 16, 2004, 08:54:36 PM »
You might want to look into getting a more powerful CPU.  Also, check that the monitor cable itself is not loose on the back of the A1200.
Michael
 

Offline Abou27Topic starter

  • Sr. Member
  • ****
  • Join Date: Oct 2003
  • Posts: 306
    • Show only replies by Abou27
    • http://www.renault-agriculture.co.uk/forums/
Re: Intermittent A1200 problems caused by PSU?
« Reply #2 on: February 16, 2004, 09:05:45 PM »
Thanks.  I've gone carefully over the cables and can't see any problems.  I know I ought to get a more powerful PSU (and CPU) but it has been running ok for quite some time.  I was really concerned by the affect on the monitor when computer was switched off (and therefore PSU too).  Monitor and PSU are plugged into different sockets with surge protectors on each.  Could loose wires in PSU cause these problems and are the A500 ones safe to open up and fiddle with?
 

Offline Matt_H

Re: Intermittent A1200 problems caused by PSU?
« Reply #3 on: February 17, 2004, 02:15:20 AM »
Maybe it's the monitor? Got another machine you can test it on? Or another monitor you can try the Amiga on?
 

Offline Argo

  • Hero Member
  • *****
  • Join Date: Feb 2002
  • Posts: 3219
    • Show only replies by Argo
Re: Intermittent A1200 problems caused by PSU?
« Reply #4 on: February 17, 2004, 02:57:30 AM »
Sounds like the PSU. How's it causing problems with the Monitor? Maybe the PSU is still providing some power even when switched off. Not to mention, it's probably providing an unstable power signal.
I wouldn't use that PSU anymore and start looking for another. Ever think of towering your A1200?

P.S. Do you or anyone you know have a Electronic Multi Meter? You could check the voltages and amps on the power signals going in and out of the PSU. Then you could see if the proper voltages are being supplies and if there are any wild variations.
 

Offline Abou27Topic starter

  • Sr. Member
  • ****
  • Join Date: Oct 2003
  • Posts: 306
    • Show only replies by Abou27
    • http://www.renault-agriculture.co.uk/forums/
Re: Intermittent A1200 problems caused by PSU?
« Reply #5 on: February 17, 2004, 08:01:44 PM »
Cheers for the suggestions.  I have tried another couple of PSUs and get same problem so must be monitor or (hopefully, less likely) computer.  Whilst I kind of hope its the monitor, I only got it a couple of months ago and sold my 1084s - Sod's law, eh? Anyway, better the monitor than the Amiga.
 

Offline Doobrey

  • Hero Member
  • *****
  • Join Date: Oct 2002
  • Posts: 1876
    • Show only replies by Doobrey
    • http://www.doobreynet.co.uk
Re: Intermittent A1200 problems caused by PSU?
« Reply #6 on: February 17, 2004, 10:59:51 PM »
Quote

Abou27 wrote:
the monitor picture suddenly went very pin-cushiony and stayed like that.  Curiously, making contact with the horiz adj button temporarily restored normal display


Sounds like the monitor is flakey..
I had an old Amstrad monitor that did that..and smelt hot too.

BTW, if you`re looking for a replacement SVGA monitor, don`t buy a Daewoo/Daytek one. Crap quality, and even crappier support.
On schedule, and suing