Results 1 to 6 of 6
  1. #1
    RetroSteve! My location

    Stephen Coates's Avatar
    Join Date
    Mar 2003
    Location
    Rotherham
    Posts
    2,117
    Downloads
    0
    Uploads
    0

    My CM8833 MkII broke

    *sob*

    The CM8833 MkII which I got off r6stu about 5 years ago () decided it no longer wanted to work an hour ago.

    After my Dad finally moved out of his house (where the monitor used to be located) in 2009, I brought it here and have used it instead of my Toshiba television set. Connecting a DVD Player or Freeview box to it via the composite input gives a better picture than using RGB on the television. It also has stereo speakers.

    I was just laughing at some clips on Police Stop 8 which I recorded off ITV4 on my PVR when the monitor switched off and only emitted a high frequency sound out of the speakers/headphones. This sounds does continue for a few seconds after the monitor is switched off but the frequency reduces. There is no other sound and no picture, and the green light on the front doesn't come on.

    I expect it will be repairable, but I am not sure what is wrong with it. Any ideas?

  2. #2
    Retro Addict Administrator
    My location

    Burger Time Champion, Sonic Champion Harrison's Avatar
    Join Date
    Dec 2002
    Location
    UK
    Posts
    15,600
    Blog Entries
    1
    Downloads
    6
    Uploads
    14
    My guess is the PSU capacitors have finally given up. If it had been the CRT tube you could have seen signs of it failing in the picture, and the high frequency sound coming from the speakers is a common sign of PSU fault/failure.

    You can replace the capacitors yourself, but remember they are very high voltage and can kill if not discharged correctly. And no, you can't just wait X days to ensure they are discharged because there is no way of knowing if they really are unless you test their charge. So be very careful.

    If you haven't played a classic game in years, it's never too late to start!


  3. #3
    RetroSteve! My location

    Stephen Coates's Avatar
    Join Date
    Mar 2003
    Location
    Rotherham
    Posts
    2,117
    Downloads
    0
    Uploads
    0
    Simplest way to discharge a capacitor is to short its terminals. Done.

    Thought it might be the power supply. I will have to try and investigate further.

  4. #4
    Retro Addict Administrator
    My location

    Burger Time Champion, Sonic Champion Harrison's Avatar
    Join Date
    Dec 2002
    Location
    UK
    Posts
    15,600
    Blog Entries
    1
    Downloads
    6
    Uploads
    14
    Only a guess, but have you checked if the monitor's PSU has a main fuse in it? If this is blown then it would indicate a more serious issue than the PSU being at fault itself.

    I've also read that the high pitched sound is a common fault, with 90% of the time being caused by the flyback (LOPT) getting shorted inside, causing current to pass trough the horizontal transistor, which will kill that also. So check the caps for bulges and cracks. Basically check all the capacitors.

    If you can't get it to work, someone in Manchester is selling a working one on Amibay if it interests you. Sale is here.

    If you haven't played a classic game in years, it's never too late to start!


  5. #5
    RetroSteve! My location

    Stephen Coates's Avatar
    Join Date
    Mar 2003
    Location
    Rotherham
    Posts
    2,117
    Downloads
    0
    Uploads
    0
    Quote Originally Posted by Harrison View Post
    If you can't get it to work, someone in Manchester is selling a working one on Amibay if it interests you. Sale is here.
    Looks nice, but there is no way I am carting one of those all the way from Manchester.

    The fuse doesn't look like it has blown. I will test it properly later though just to be 100% sure.

    I do hope the flyback transformer isn't knackered as that will probably mean finding a replacement.

  6. #6
    Retro Addict Administrator
    My location

    Burger Time Champion, Sonic Champion Harrison's Avatar
    Join Date
    Dec 2002
    Location
    UK
    Posts
    15,600
    Blog Entries
    1
    Downloads
    6
    Uploads
    14
    If it is I know someone I can pass you on to who can refurbish it or give you a swap out replacement.

    If you haven't played a classic game in years, it's never too late to start!


Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Copyright classicamiga.com