Ensoniq ASR-10 (Keyboard test failure on boot)

Synth Repair
1

I am repairing an Ensoniq ASR-10 keyboard. It would not boot due to a keyboard test failed (also the enter/yes button is not working so it would not finish booting. I have buttons on order so I think I can fix that part.

As for the keyboard failure. I have read that the most common causes would be:

  1. fuses 3 or 4 - (mine do not appear to be blown)
    2)poorly connected or damaged ribbon cable from keyboard to main board (when i opened the cases the ribbon cable looked like it was connected well. I have not replaced it yet.
    3)the two halves of the keyboard have a poor connection. This is the one I am worried about. I have taken everything off the board except the keybed itself. Before I open that can of worms do any of you know of a video or site that describes the repair for this (which i think is hard wiring the two halves together)?

I appreciate any thoughts. I have done alot of searches for repair info and i have the service manual but it does not get into that repair that i can see. Also, youtube hasnt yielded a good how to for this specific item.

3

Hi, my ASR 10 was just repaired. I was having the same problem, No Keyboard Detected error. So I looked through the service manual and it mentioned that there are 5 fuses. If the 4th fuse blows usually the 3rd fuse blows right after. An electronic technician that repaired my power supply told me that for each module or P.C. board theres a fuse. The 1st one to go is always assigned to the largest P.C. boatd which is the keyboards P.C. board. I myself looked at the fuses before sending the power supply to him. None of them looked gray and smokey on the inside. They all looked clear. He told me that I had 4 blown fuses on mine as well as bad capaciters.Everything he told me made sense. 1st problem was no keyboard, that’s 1 fuse blown, 2nd problem no lights on the display that’s fuse 2 blown, now it was in self test mode. 3rd problem no led lights under display that’s fuse 3 blown. 4th problem no more disk drive lights or activity, that’s tube 4 blown. Also it was an original 1992 power supply. That’s super old. It lasted a very long time before the large capacitors died and fuses blown. Bro, check out this guy. He’s on ebay. His user name is: musicman 528 he’s selling refurbished Ensonic ASR 10 complete power supplies. You 1st buy it from him for $100.then he’ll send you a message in your ebay messages with his address to send him your complete ASR 10 power supply. As long as your power supply has alli t’s parts. He will send you a fully working one as soon as he receives your dead power supply. He’s really cool and even called me on my cell to tell me what went wrong on mine. He also ships quickly. He’s in the state of Virginia. Check it out and bring your ASR 10 back to life.Enjoy!

4

P.S. Another thing I forgot to mention is: before you remove any parts to get your power supply and remove it. Take photos with your cell of all connection jumper wires and power supply connection cables
I also wrapped a piece of masking tape around each cable like a self made tag and wrote on the masking tape with a pen :pen: as to where the connection wires went to. Make sure when handling the boards and removing them to keep the screws from each board in a seperate zip lock that you label with a small piece of note paper as to where they go back and their color ie; silver/ or black. Use rubber gloves to avoid static discharge on boards and components from blownig. Note: to get the power supply out you have to take the entiire ASR 10 apart. It’s about a 6 hour job. Take your time. Do it carefully. The technician asked me if I was plugging into the wall AC directly without a surge protected power strip. I was using a power strip but it was cheap and it’s surge protector was only 900 Joules. He told me that I must have had a power spike in my home’s electricity and had I not plugged into the surge protector would have caused internal boards to fry and be dead. So I purchased a much better power surge protector/ power strip. It’s a Belkin and protects up to 4300 Joules. Instad of the flimsy old 900 Joules I had it connected to. I bought mine on Amazon for $46.00