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  • #31
    Originally posted by jbird604 View Post
    If you borrow a board from another organ and there are EPROM's on it, do swap the EPROM's so the properly characteristics of your 5400 will be preserved.
    John,

    Thanks for the advice.

    Odd thing. I just went out and turned the organ on, and it worked fine. Go figure. Now I'm going to warm up the garage to see if the issue is heat related. In any event, I'm going to pull an EG-1 card from my ADC-4300 just in case one gives out during rehearsal on Tuesday. I'll let you know how it turns out.

    Great advice on this Forum, as usual.

    Michael
    Way too many organs to list, but I do have 5 Allens:
    • MOS-2 Model 505-B / ADC-4300-DK / ADC-5400 / ADC-6000 (Symphony) / ADC-8000DKC
    • Lowrey Heritage (DSO-1)
    • 11 Pump Organs, 1 Pipe Organ & 7 Pianos

    Comment


    • #32
      Originally posted by myorgan View Post
      I'll let you know how it turns out.
      OK, officially frustrated here.:-P

      Went out to the garage after heating it up to around 55˚-60˚. Practiced the organ for approximately 2 hours--then it happened--little-by-little. The more stops and the more couplers I added, the faster it seemed to come on. The issue seems to be related to time and heat.

      So then:
      • I pulled the Alterable Voice EG-1 card (Slots 3 & 4). No change.
      • I replaced the Alterable Voice EG-1 card, then pulled the Great/Pedal/Choir EG-1 card (Slots 5, 8, 9, 10, & 16). No change.
      • I replaced the Great/Pedal/Choir EG-1 card, then pulled the 32' & 16' Pedal EG-1 card (Slot 14). No change.
      • I then removed all EG-1 cards in the organ. No change.
      • I then thought about the Brass Choir card, and DG-3 card. No change.
      • I then pulled the TG-4 card. No change.
      • I then pulled the FG-2 card, and still no change.
      • Time to go to the middle of the cage. I pulled the AP card. No sound, but when re-seated, no change.
      • I went to the other end of the cage. The AV (Alterable Voice) card when removed didn't help.
      • The KA-1 and MA-1 cards didn't appear to have any issues when reseated.
      BTW, only the EG-1 cards were pulled when the organ was on. The rest, I pulled with the organ off.

      Tomorrow at church, I'll remove the USMA-1 and USKA-1 from the organ there, and try them. Of course the organ will have to warm up first to create the issue, but it's worth a try.

      Thank you for your support, and I will keep you posted.

      Michael

      P.S. I got the following recording today using the Tascam recorder. Please ignore the mistakes--I was transposing a 5th at sight.
      Attached Files
      Way too many organs to list, but I do have 5 Allens:
      • MOS-2 Model 505-B / ADC-4300-DK / ADC-5400 / ADC-6000 (Symphony) / ADC-8000DKC
      • Lowrey Heritage (DSO-1)
      • 11 Pump Organs, 1 Pipe Organ & 7 Pianos

      Comment


      • #33
        Good troubleshooting, Michael. Did you check the +5 and +/- 15 volt outputs on the USPS-3 when the problem occurred? Since you tried just about everything in the cage except the MA and KA boards, if it isn't either board, that points to the USPS-3. Or the dreaded backplane trouble.

        I know how frustrated you must be. When the MDS was down at church last spring I would work on it for hours at a time. Replaced power supplies with two different spares, even ordered a new MN board. Took all the cage boards, a few at a time, to other organs for testing, but everything seemed to work fine in other organs, just couldn't make the organ play at church.

        It was only by accident that we realized it was the backplane board. Discovered that pressure on the board at a certain point near the USAV socket would affect the operation, then started testing the traces with a meter, found that a vital trace carrying clock data had been eaten away underneath the USAV socket. Battery leakage that had happened years earlier had finally taken its toll.

        Knowing I didn't care if the card reader ever worked again, I took my cutting pliers to that socket and tore it off the board, where the damage could then be clearly seen and fixed with a jumper.

        Just telling you the story to show how difficult it can be to find the real problem in a case like this. Our aging ADC organs are possibly coming to a point where more aggressive repairs will be called for. But I'm sure once we get past a certain hump they will be good as new again!

        In your case, I'm thinking it will be either the MA or KA or else the power supply. Be sure to have your meter at the ready when testing, so that when the problem occurs you can test the supply quickly. Look for the +5 to either drop below 4.6 or else to develop AC ripple.

        If the +5 is dropping low, you MIGHT be able to remedy by adjusting the small pot on the board that regulates that voltage. But chances are the regulating circuit will have gone haywire and will require replacement or repair.
        John
        ----------
        *** Please post your questions about technical service or repair matters ON THE FORUM. Do not send your questions to me or another member by private message. Information shared is for the benefit of the entire organ community, but other folks will not be helped by information we exchange in private messages!

        https://www.facebook.com/pages/Birds...97551893588434

        Comment


        • #34
          Originally posted by jbird604 View Post
          Good troubleshooting, Michael. Did you check the +5 and +/- 15 volt outputs on the USPS-3 when the problem occurred? Since you tried just about everything in the cage except the MA and KA boards, if it isn't either board, that points to the USPS-3. Or the dreaded backplane trouble.
          [snip]
          In your case, I'm thinking it will be either the MA or KA or else the power supply. Be sure to have your meter at the ready when testing, so that when the problem occurs you can test the supply quickly. Look for the +5 to either drop below 4.6 or else to develop AC ripple.

          If the +5 is dropping low, you MIGHT be able to remedy by adjusting the small pot on the board that regulates that voltage. But chances are the regulating circuit will have gone haywire and will require replacement or repair.
          I just pulled 4 boards from my ADC-4300 at church about an hour ago (1-EG-1; 1-AP-1; 1-KA-1; and 1-MA-2A). My only question has to do with the MA-2A. It it OK to place that board into the MA-2 slot of the ADC-5400? I know you said some advanced versions could replace older versions, but I'm not sure about that particular board.

          On one of the boards, the little white label came off the EPROM installed. I forget the precautions with that window--is it sunlight (i.e. UV rays), or just plain light that can affect the ERPOM? I believe it came from the EG-1 board.

          I will attempt to get the problem to replicate itself today before I load the organ for transport. My gut is telling me it's either the AP board or the KA board because it is sounding like garbled audio data or keying data, but time and experimentation will tell.

          Thanks again, everyone, for the guidance.

          Michael
          Way too many organs to list, but I do have 5 Allens:
          • MOS-2 Model 505-B / ADC-4300-DK / ADC-5400 / ADC-6000 (Symphony) / ADC-8000DKC
          • Lowrey Heritage (DSO-1)
          • 11 Pump Organs, 1 Pipe Organ & 7 Pianos

          Comment


          • #35
            Yes, the MA-2A can be used in place of the MA-2. (Note that if you had asked about doing it the other way around -- putting an MA-2 where there had been an MA-2A, I would say maybe not.)

            The garbled sound I heard on your recording sounds like the MA or KA board acting up. But I wouldn't rule out anything at this point. At least you have some boards at hand to quickly sub in and out, which is a huge advantage over trying to figure this out with no spare boards.

            The question may be whether a cage board is acting up because it's bad, or because the +5 volt power supply goes down. You will have to use your meter to test the power supply once the trouble starts.

            I think the EPROMs are only affected by UV light, but it's wise to avoid exposure to all light, espeically bright light. Stick a piece of masking tape over the hole if you need to.
            John
            ----------
            *** Please post your questions about technical service or repair matters ON THE FORUM. Do not send your questions to me or another member by private message. Information shared is for the benefit of the entire organ community, but other folks will not be helped by information we exchange in private messages!

            https://www.facebook.com/pages/Birds...97551893588434

            Comment


            • #36
              John,

              I will be checking the voltage shortly this afternoon.
              Originally posted by jbird604 View Post
              I think the EPROMs are only affected by UV light, but it's wise to avoid exposure to all light, espeically bright light. Stick a piece of masking tape over the hole if you need to.
              I just found the answer in an old post you provided here: http://www.organforum.com/forums/showthread.php?39010. I believe my ADC-4300 cage chart has the correct label marked, and I also have the old photographs of the label still on the chip when I first purchased the organ--yet another reason to remove all the cards in the cage when you purchase an organ! I should be good there.

              It may be a day or two before I can post any results--I'm looking at 6:30AM-10:00PM through Thursday, so it may be a while. Thanks for all the help.

              Michael

              P.S. Was that DC or AC voltage? I'll assume DC unless I hear otherwise--or else it's probably marked somewhere.
              Last edited by myorgan; 10-30-2016, 10:07 AM.
              Way too many organs to list, but I do have 5 Allens:
              • MOS-2 Model 505-B / ADC-4300-DK / ADC-5400 / ADC-6000 (Symphony) / ADC-8000DKC
              • Lowrey Heritage (DSO-1)
              • 11 Pump Organs, 1 Pipe Organ & 7 Pianos

              Comment


              • #37
                All cage operating voltages are DC and should read fairly close to the voltage specified on the labels. The + and - 15 are not rightly regulated and could be off a half volt either way. The +5 should be within a couple tenths of a volt. If not, try adjusting the small pot on the supply chassis (have to pull it out of the cage to tinker, then put it back in to test).
                John
                ----------
                *** Please post your questions about technical service or repair matters ON THE FORUM. Do not send your questions to me or another member by private message. Information shared is for the benefit of the entire organ community, but other folks will not be helped by information we exchange in private messages!

                https://www.facebook.com/pages/Birds...97551893588434

                Comment


                • #38
                  Folks,

                  I just realized I had not updated the actual problem John & I discovered with the organ. I guess I got too busy with performances--it was a busy fall!

                  After swapping boards, the issue still existed, so I purchased some cage cards from Daffer (those not compatible between the 5400 & 4300), but have not installed them yet. So, to get through a particular performance, John suggested I send the offending Choir channel through the antiphonal, and change all my pistons to reflect that change. It fixed the issue permanently!

                  Evidently, another component prone to possible failure are the Antiphonal Relay cards. I discovered that issue after following John's advice. I had sent two ADC amplifiers out for repair, and when the first amplifier came back, the issue still existed. The only item I had not bypassed in the cage-to-speaker chain was the antiphonal relay cards.

                  I am waiting for the other amplifier to come back for an upcoming performance, and will keep you posted on those results. Meanwhile, I have a spare relay card I will probably use for the performance.

                  John, Dave, et al., thank you for all your advice and help!

                  Michael
                  Way too many organs to list, but I do have 5 Allens:
                  • MOS-2 Model 505-B / ADC-4300-DK / ADC-5400 / ADC-6000 (Symphony) / ADC-8000DKC
                  • Lowrey Heritage (DSO-1)
                  • 11 Pump Organs, 1 Pipe Organ & 7 Pianos

                  Comment


                  • #39
                    Originally posted by myorgan View Post
                    So, after practicing all afternoon, I went in the house to get my wife's *Pad to make sure the organ is in tune for the upcoming performance. When I returned, this is what I heard:
                    • [ATTACH]24125[/ATTACH]--This was me pressing Piston #1, and playing on the Choir, Great, and Swell
                    • [ATTACH]24126[/ATTACH]--This was me trying to play with my first attempt. I tried full organ that time. The clicks you hear are me changing pistons.
                    Hopefully, my FINAL update!

                    Tonight I was using the organ for Symphony rehearsal, and was having issues hearing certain stops. Because everyone was warming up, I didn't have the chance to try the organ before the rehearsal. When it came time for the organ to come in--the same issue as before!!! I was hoping to at least get two hours out of it, but this time I was prepared!

                    I had ordered 4 spare boards from a dealer online who was parting them out. The boards were a TG-4, TG-5, KA-1, and one other board (perhaps EG-?). On a hunch, I replaced the KA-1 board after verifying all the numbers matched and that the gold traces matched. Powered on the organ, and the problem is now fixed! I hadn't told my wife about purchasing the boards, but tonight she realized why I purchased spares (she plays for Symphony as well). She was really glad to know I just spent around $100 for the replacement board instead of the price Allen charges to repair them.

                    After looking at the board, I think the issue had something to do with the board next to it. The next board is the AV-1 board, and the batteries had been removed from the board, but the connectors they used for the connecting wires may have caused damage to the solders on the adjacent KA-1 board. I guess I'll never know what caused it until I have the board repaired.

                    Well, it's nice to have it working again. Bottom line, if you hear what the quoted recordings sound like, try replacing the Keyboard Array card USKA-1.

                    Michael
                    Way too many organs to list, but I do have 5 Allens:
                    • MOS-2 Model 505-B / ADC-4300-DK / ADC-5400 / ADC-6000 (Symphony) / ADC-8000DKC
                    • Lowrey Heritage (DSO-1)
                    • 11 Pump Organs, 1 Pipe Organ & 7 Pianos

                    Comment


                    • #40
                      Glad you got to the bottom of that. This is a new one to me, but I'm never surprised any more at the problems showing up in these ADC models as they age. I think I've posted at length about the way the leaking battery on the USAV board damaged the backplane of our MDS-45 at church, and it took me weeks to figure out why the organ was dead.

                      It's good that you have some spare boards on hand. Yes, Allen charges many hundreds of dollars for those boards, even the ones that are repairable. You did well!
                      John
                      ----------
                      *** Please post your questions about technical service or repair matters ON THE FORUM. Do not send your questions to me or another member by private message. Information shared is for the benefit of the entire organ community, but other folks will not be helped by information we exchange in private messages!

                      https://www.facebook.com/pages/Birds...97551893588434

                      Comment


                      • #41
                        Originally posted by jbird604 View Post
                        It's good that you have some spare boards on hand. Yes, Allen charges many hundreds of dollars for those boards, even the ones that are repairable. You did well!
                        Fortunately, that board doesn't have any EProms to switch over, so it was quite a quick repair. I was worried because the original board was the standard green color with a Serial Number in the 1000s, but the replacement board was white colored with a Serial Number in the 100s. I was worried that the change in generation/years/age would mean the old board was one that had been removed from an organ due to needing repair, but it appears it may have come from a repair kit, and was never used. Good for me--new (old) board, but presumably stable.

                        Still waiting on the 2ndamplifier repair, but fortunately it's a spare--just in case.

                        Michael
                        Way too many organs to list, but I do have 5 Allens:
                        • MOS-2 Model 505-B / ADC-4300-DK / ADC-5400 / ADC-6000 (Symphony) / ADC-8000DKC
                        • Lowrey Heritage (DSO-1)
                        • 11 Pump Organs, 1 Pipe Organ & 7 Pianos

                        Comment


                        • #42
                          The KA board is one that I have only had to replace one time that I can remember in all my years of dealing with ADC and MDS organs. Its full name is "Key Assigner" and I assume that it somehow routes the keying data coming into the cage to the appropriate TG boards for processing into audio. It must be a fairly reliable board, since it seems to fail so rarely.

                          The real issue with ADC cages as time goes by is going to be battery damage. Even though Allen issued a warning a very long time ago about removing all batteries from all boards, I still see batteries mounted on boards now and then. Sometimes they have leaked, sometimes not. When they leak, the damage may appear to be limited, and you can often just clean up the mess and solder in a jumper or two if a trace was eaten away, and the board may then work.

                          But the question is how much damage the battery leakage may have done that is not easily seen. In the case of the MDS at my church, before I even got that organ the battery on the USAV board had leaked and the board had been removed by a tech I suppose. The board socket on the cage backplane had gotten a bit of acid into it, and that acid apparently wasn't adequately cleaned out.

                          Years later, with the organ in service at my church, it suddenly stopped working. It took weeks of troubleshooting (not all the time of course, just when I could spare the time) to discover what was wrong. The acid that had gotten into that socket had worked its way to the backplane board and had eaten through a trace that carried the timing signals to the USFG boards that reside at the far end of the cage. No frequencies, no sound!

                          Since I had no need to make the card reader work again, we just ripped that socket out of the cage, a process that involved pliers, knives, chisels, and other heavy duty tools. Those sockets are NOT meant to be removed! Once the socket was removed, it was clear what had happened. We cleaned up the mess and (I hope) fully neutralized the acid, then soldered on a wire jumper to carry the signal around the damaged area of the board.

                          So, I certainly hope that you don't have board damage that isn't yet apparent. If you have more troubles with this same area of the cage, you may be forced to have the cage worked on -- or get out your heavy tools and do it yourself!
                          John
                          ----------
                          *** Please post your questions about technical service or repair matters ON THE FORUM. Do not send your questions to me or another member by private message. Information shared is for the benefit of the entire organ community, but other folks will not be helped by information we exchange in private messages!

                          https://www.facebook.com/pages/Birds...97551893588434

                          Comment


                          • #43
                            Originally posted by jbird604 View Post
                            So, I certainly hope that you don't have board damage that isn't yet apparent. If you have more troubles with this same area of the cage, you may be forced to have the cage worked on -- or get out your heavy tools and do it yourself!
                            When I took the cards out for photos, I looked at the back of the cage, and everything appears to be clean, so . . . . Time will tell. Isn't it funny how much one design issue could create so many problems with an organ decades later?

                            Well, off to the races tomorrow! The organ stayed on today for over 6 hours, and held up great. Thanks so much for your help, John!:-)

                            Michael
                            Way too many organs to list, but I do have 5 Allens:
                            • MOS-2 Model 505-B / ADC-4300-DK / ADC-5400 / ADC-6000 (Symphony) / ADC-8000DKC
                            • Lowrey Heritage (DSO-1)
                            • 11 Pump Organs, 1 Pipe Organ & 7 Pianos

                            Comment


                            • #44
                              Hi all. Merry Christmas for you all!
                              I have an issue. My Allen digital ACD-220 amplifier bangs when turn-off. I found out that if I turn off volume ir remove connection on channel-2, this problem disapiers. I dont know anything in schemas, so it would be nice if I could chamge all amplifier. I need "Allen organ amplifier Model D-40, Assembly no 905-1552-2, Schematic No 081-0548". But there are no such part (i didnt find) in internet sell. I find only "Allen Organ ADC Two Channel, Dual Amplifier 905-1566-2, Schematic No 081-0554". Is this part (905-1566-2) comatible with ACD-220? Will it solve my "bang" problem?

                              Thank you for your time and help!
                              Lina

                              Comment


                              • #45
                                Originally posted by lina View Post
                                I have an issue. My Allen digital ACD-220 amplifier bangs when turn-off. I found out that if I turn off volume ir remove connection on channel-2, this problem disapiers. I dont know anything in schemas, so it would be nice if I could chamge all amplifier. I need "Allen organ amplifier Model D-40, Assembly no 905-1552-2, Schematic No 081-0548". But there are no such part (i didnt find) in internet sell. I find only "Allen Organ ADC Two Channel, Dual Amplifier 905-1566-2, Schematic No 081-0554". Is this part (905-1566-2) comatible with ACD-220? Will it solve my "bang" problem?
                                Lina,

                                Welcome to the Forum!

                                The "bang" you mention is probably the mute relay failing in the D-40 amplifier you have. The mute relay in the amplifier keeps sound from going to the speakers until a few seconds after the organ is turned on.

                                While I'm not sure the ADC Amplifier is a direct replacement for the D-40, I believe it certainly could be used. That said, however, it would probably be too much power for your organ's sound. If you wait until the organ techs weigh in, they can provide definitive answers to your questions.

                                Meanwhile, another solution would be to temporarily put the amplifier on a power strip that can be turned on after the organ is turned on. Then, when turning the organ off, you can turn the power strip with the amplifier off before turning the organ off. That should prevent your "bang" for the time being.

                                Hope that helps temporarily.

                                Michael
                                Way too many organs to list, but I do have 5 Allens:
                                • MOS-2 Model 505-B / ADC-4300-DK / ADC-5400 / ADC-6000 (Symphony) / ADC-8000DKC
                                • Lowrey Heritage (DSO-1)
                                • 11 Pump Organs, 1 Pipe Organ & 7 Pianos

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