Help with dead Commodore 1802

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  • R_J
    Badcaps Legend
    • Jun 2012
    • 9515
    • Canada

    #181
    Re: Help with dead Commodore 1802

    If the lamp is in place of this inductor then it will still pass the voltage to that part of the circuit, It might be slightly low, likely around 100vdc. You can remove the lamp from the 121 volt line and reconnect the coil, I suspect you will then get a full width screen also.
    Last edited by R_J; 02-19-2020, 06:47 PM.

    Comment

    • stj
      Great Sage 齊天大聖
      • Dec 2009
      • 30928
      • Albion

      #182
      Re: Help with dead Commodore 1802

      btw, can you take a picture of the power switch?
      i want to see if it's like the one on the phillips CM8833-II (commodore 1084-s)

      Comment

      • roadrash
        Badcaps Veteran
        • Oct 2015
        • 490
        • U.K.

        #183
        Re: Help with dead Commodore 1802

        Originally posted by stj
        btw, can you take a picture of the power switch?
        i want to see if it's like the one on the phillips CM8833-II (commodore 1084-s)
        These switches are a nuisance and I can't find replacements anywhere and end up bridging the contacts and turning it on/off at the mains wall plug.
        Attached Files

        Comment

        • roadrash
          Badcaps Veteran
          • Oct 2015
          • 490
          • U.K.

          #184
          Re: Help with dead Commodore 1802

          Originally posted by R_J
          If the lamp is in place of this inductor then it will still pass the voltage to that part of the circuit, It might be slightly low, likely around 100vdc. You can remove the lamp from the 121 volt line and reconnect the coil, I suspect you will then get a full width screen also.
          Ok I found I had put it back in when you asked me to earlier put everything back. I am begining to think it might be safe now to put the resistor R801 back in now.
          I currently have 2 bulbs in place of this resistor.
          I am still a bit unsure as we still never found what was causing that short.
          What do you think?

          Comment

          • stj
            Great Sage 齊天大聖
            • Dec 2009
            • 30928
            • Albion

            #185
            Re: Help with dead Commodore 1802

            does that switch normally solder to the board, or have wires on it?
            if it's wires then a replacement wouldnt be hard.

            on the 8833-II i removed the pushbutton from the case and fitted a rocker switch instead.
            i'll get photo's over the weekend if you want.
            not exactly original, but on the 8833-II the switch is at the back out of sight.

            Comment

            • roadrash
              Badcaps Veteran
              • Oct 2015
              • 490
              • U.K.

              #186
              Re: Help with dead Commodore 1802

              Originally posted by stj
              does that switch normally solder to the board, or have wires on it?
              if it's wires then a replacement wouldnt be hard.

              on the 8833-II i removed the pushbutton from the case and fitted a rocker switch instead.
              i'll get photo's over the weekend if you want.
              not exactly original, but on the 8833-II the switch is at the back out of sight.
              Yes it has wired connections and the switch assembly is screwed onto the plastic casing.

              Comment

              • stj
                Great Sage 齊天大聖
                • Dec 2009
                • 30928
                • Albion

                #187
                Re: Help with dead Commodore 1802

                https://www.rapidonline.com/power-pcb

                Attached Files

                Comment

                • roadrash
                  Badcaps Veteran
                  • Oct 2015
                  • 490
                  • U.K.

                  #188
                  Re: Help with dead Commodore 1802

                  Originally posted by stj
                  Thanks for that STJ that's a great help. Ive got quite a few Commodore and Phillips CM monitors for all the Amiga kit I have here. I sold My Original Amiga A1000 and Amiga branded matching 1081 monitor last year. I still have a few A500's, a A1200 and my big A2000 with hard drive and IBM XT bridgeboard inside. I've got tons of software too. If your looking for anything Commodore just ask.

                  Comment

                  • roadrash
                    Badcaps Veteran
                    • Oct 2015
                    • 490
                    • U.K.

                    #189
                    Re: Help with dead Commodore 1802

                    I want to thanks both of you guys STJ & RJ for helping me finally get this commodore monitor fixed. I put the Wire wound resistor back it and it doesnt blow now and the display fills the screen and i can hear audio too. I will give it a test with a video signal when I more time but I am glad its finally fixed and I doubt I could have done that without the
                    help from you two.
                    I have learned loads and just hope I don't forget it all as I have big Issues with memory problems caused by my Multiple Sclerosis which is most difficult as I find it hard to learn new things and make them stay in my memory although I can remember all my past history.
                    I've got it all stored on my hard drive so if i ever need to use it again I can. RJ that Schematic that you did for me showing where it changed from to DC was brilliant and made it all a lot easier for me to understand.
                    Thanks again guys your brilliant and cant thank you enough.

                    cheers!
                    Jon

                    Comment

                    • R_J
                      Badcaps Legend
                      • Jun 2012
                      • 9515
                      • Canada

                      #190
                      Re: Help with dead Commodore 1802

                      If the small spst part of the switch is not used, this might work: https://www.conrad.com/p/pwl-2p1tl-6...h-1-pcs-701606

                      There is also the ALPS SDGA3P
                      Attached Files
                      Last edited by R_J; 02-20-2020, 12:44 PM.

                      Comment

                      • stj
                        Great Sage 齊天大聖
                        • Dec 2009
                        • 30928
                        • Albion

                        #191
                        Re: Help with dead Commodore 1802

                        there is no standby trigger on the CBM monitors, just DPST mains switching.

                        Comment

                        • roadrash
                          Badcaps Veteran
                          • Oct 2015
                          • 490
                          • U.K.

                          #192
                          Re: Help with dead Commodore 1802

                          Originally posted by stj
                          you should check the B+ voltage and compare it to the manual - it can be ajusted.
                          it's DC btw.
                          Just wondering what is this B+ adjustment and I cannot see anything in the manual about it. The manual only mention static & dynamic convergence.

                          Comment

                          • roadrash
                            Badcaps Veteran
                            • Oct 2015
                            • 490
                            • U.K.

                            #193
                            Re: Help with dead Commodore 1802

                            Originally posted by stj
                            found one on ebay. i will just have to swap over LED.

                            https://www.ebay.co.uk/itm/RVFM-PT-M...MAAOSwgARa58oX

                            Comment

                            • R_J
                              Badcaps Legend
                              • Jun 2012
                              • 9515
                              • Canada

                              #194
                              Re: Help with dead Commodore 1802

                              Originally posted by roadrash
                              Just wondering what is this B+ adjustment and I cannot see anything in the manual about it. The manual only mention static & dynamic convergence.
                              There is no B+ adjustment, just check if it is close to the 121vdc as indicated on the schematic, if it's off a couple volts either way, thats not an issue.
                              Last edited by R_J; 02-22-2020, 04:57 PM.

                              Comment

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