Today I successfully managed to install the Cool Blue Replacement LCD into my Yamaha SY-77. Although my former LCD was the stock version and working properly, I was bothered by two significant things. First, there was an annoying hum from the power inverter that was driving me nuts when playing the SY77. The Noise was filtering through the outputs and headphones which was really irritating and it’s a known problem with the Yamaha SY-77 Synthesizer. The second issue was that I could practically not see a thing when playing the synth at night or in a dark club. I had to use a makeshift flashlight to see the stock LCD screen. Thus, I knew it was time to take the plunge and replace the screen with the custom cool blue version as pictured from my synth in this post.
A huge thanks to Derek Cook from Yamaha Forums UK and EX5tech for providing the instructions to replace the LCD. You can find the PDF file that I used at his website here. A couple of things I’d like to point out that I did that are different from the PDF are as follows:
1. I chose to desolder the ribbon lead and header on the original LCD PCB and solder it on the new board. Living in Japan, I figured it would be a nightmare tracking down the necessary replacement cable ribbon and connectors. I became quite handy with the soldering iron after my Juno 106 project, so I decided to try my luck with removing the original ribbon connector. Indeed it was tricky and it took some patience. I used both a Solder Sucker and Copper Wick to remove the solder. Fortunately there wasn’t much solder on the board. You have to wiggle it a bit, but it actually came out nicely due to the pins being right angled. I then took the Solder Iron and cleaned the pins a bit to ensure they would fit the new LCD board.
2. It’s important to note that for the SY-77 specifically, the wire colors are crossed. Naturally one would think RED goes to A and BLACK goes to K when reading the PDF, but it’s actually the opposite. I made this mistake the first time I turned on the synth and noticed no backlight. I then switch the wires and the LCD with backlight powered up beautifully as shown.
3. It took me a total of five hours to get the LCD out of the SY-77 synth, desolder and solder the components, and finally to put the entire synth back together again. It’s a HUGE chore to take that puppy apart, so allow enough time to do things right or you’ll quickly get overwhelmed. It’s actually very easy to take the synth apart, but you definitely need to organize your screws, wires, and all the pieces that you remove.
The LCD is slightly thicker than the original so expect a tight fit, but it should be comfortable nonetheless. I didn’t have to force anything, but I could tell I had very little play left.
All in all, the LCD cost me $42 bucks to get. I used all the wiring and connectors from the stock LCD so I didn’t need any additional parts. Yes soldering is definitely required for this project. The connector alone has 20 pins to desolder and then solder back together again. Plus you have to solder two wires for the LCD backlight power. You also may need to splice the wiring as I did to extend the length as using the original will be too short.
Whether your current Yamaha SY-77 LCD is working or broken, I can’t recommend highly enough to replace it with the cool blue LCD. It’s simply magnificent. It’s super quiet and ultra bright in in the dark. It definitely makes the SY-77 fun and cool to play with and perhaps even increases the value a wee bit.
My only word of advice is to go SLOW! I’m NOT an electronics guru by any means. I only started soldering synthesizers less than a year ago. I just take my time and it also helps to practice on old crappy stuff you don’t use anymore. If anyone has questions, please feel free to comment or send me an email. I’d be more than happy to help.