Besides its visual impact, I saw its value as a low profile controller when I'm not hamming it up out at the front of the stage. It's a well designed controller - lightweight, comfortable to play, definitely designed by musicians. Velocity sensitive keyboard with aftertouch, wheels for modulation and pitch bend, volume pot, three momentary buttons (no idea what they do). I located an owner's manual for it. Then I applied power...
...and that's where the trouble began. The embedded system was barely functioning then it stopped working altogether. No service manual or schematic could be located, nor was the original Lync company still existing. The circuit board wasn't too complex, I'm no stranger to embedded systems, so I could tackle the problem blind. The first thing I did was recap and replace the BR2325 coin battery with a CR2450 (same voltage, higher current). Completely dead.
Probed the TL7770-5 voltage supervisor IC that could hang up the CPU. The TMS370 quad leadless IC is tough to probe as I didn't have any leads that could extend down the socket, and I couldn't figure out how to extract the IC from that tight grip on the socket. So I probed the RAM and EPROM IC power pins, and their power pins were OK. The *RESET pin on the TL7770 was stuck low so the CPU won't be be running.
When I pulled the base of a transistor in the reset buffer to the CPU, the *RESET pin went high. Replaced the transistor and the *RESET pin now stays high, so the CPU should run. Nothing. Probing the WR/RD/CE/data pins on the memory ICs showed no signs of CPU life.
Checking the clock pins showed intermittent signal, so I replaced the crystal. Still no clock signal at all - I might have installed the incorrect type of crystal.
I had to suspend work when life interrupted. I'm not giving up as I have other ideas, but right now reviving the LN1000 is not a priority. But I noticed that few LN1000 show up for sale and when they do they are not working. There's a reason why these things turn up broken.
Fast forward to 2022 and a resurrected Lync company is making LN1000 Keytars again. I was going to grab one, then the company went under among difficulties with finances and supplier issues for the polymer cases.
"Polymer cases" was a great big clue. Polymer stores static electricity which can damage delicate electronic ICs, and the LN1000 circuit board has static sensitive ICs. As time progresses, the polymer case accumulates more static charge. There's only one way to drain the charge, and it's not a good way. As the charge gets high enough, all it takes is an arc from the case to the circuit board looking for a path to ground... and poof that arc can blow static sensitive ICs. I haven't explored this yet, but not exactly a brilliant move for the designer(s). Probably why these things show up broken.
Someday this thing will live again ("It's alive... IT'S ALIVE!!").
