Piano, Organ, and Keyboard/Availability of AOB Schematics

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Question
Hi Tom!

Thanks for your longtime support for the AOB owner community!

We have a beloved AOB (Opus 173, spec 794) that we have not given up hope on...yet. Some young engineering students at the local college have an interest in performing some of the required maintenance tasks and in the process also gain an understanding of its internal operation, which (speaking as a career engineer) is difficult without a schematic. Is this documentation available for AOBs?

Thanks as always for your advice and assistance!

John

Answer
Hello John, Yes we have all the schematics for the organs.  However, it takes a bit of research to compile the proper schematics for your specific instrument since most AOB organs were custom.  Every AOB organ was accompanied by a set of schematics.  I assume yours has been misplaced or taken by a technician for "safe" keeping?  Have you checked inside the organ, the bench, obscure organ office file, or with the person who has taken care of the instrument in the past?

Because the organs utilize pure logic and multiplexing, the operation is fairly easy to troubleshoot (with schematics, of course).  However, the logic boards can be difficult to troubleshoot because, unless you have extender boards, the only access to the boards are from their rear connectors. Hooking onto the terminals of the connectors can be tedious.  Because of this, before I go into the field to work on an AOB organ, I first ascertain whether the problem is likely to involve one or more of the logic boards.  I then have the boards pulled, wrapped in aluminum foil and sent to our shop where we have the original test jigs to test the boards in seconds.  Once the problems have been located, we make the necessary repairs and ship the boards back. Many times, this is all that is necessary to make a repair.  If not, then at least you will know the logic boards are good and will know to look elsewhere.

Also, if you provide us with detailed symptoms, we can usually suggest where to look and can usually name the specific component likely to be bad.

I understand you are planning to have engineering students troubleshoot the instrument as a project.  If so, I'd like to be involved, to keep the procedures on track, to assure the organ is repaired successfully.

Please contact me at 253 863 2331 to make arrangements for copying the schematics, etc.  

Piano, Organ, and Keyboard

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Thomas Britanyak

Expertise

I am a full time organ/piano technician who has been actively involved with the design, building, repair, maintenance and installation of organs and pianos for 35 years. I began as a keyboard instrument apprentice and hold degrees in music and electronics. If you need a piano's date of manufacture, please go to http://www.pianoexchange.com/howold.htm or http://www.bluebookofpianos.com/pianoage.html I am happy to answer musical or technical questions, however, I CANNOT offer appraisals on pianos or organs. Please do not ask what an instrument is worth. For this service please contact an experienced local appraiser or try the following links: https://mmm1100.verio-web.com/blueb1/appraisal.html or http://www.57piano.com/questions.htm

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I am a full time organ/piano technician who has been actively involved with the design, building, repair, maintenance and installation of organs and pianos for 35 years. I began as a keyboard instrument apprentice and hold degrees in music and electronics.

Education/Credentials
I am a full time organ/piano technician who has been actively involved with the design, building, repair, maintenance and installation of organs and pianos for 35 years. I began as a keyboard instrument apprentice and hold degrees in music and electronics.

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