Korg Triton-Rack LCD Display has lines up/down it

I have a Triton-Rack LCD that looks like this

Syntar is out of stock and states it is the same as the LE. Does anyone have any suggestions for sources or how to fix or even have a spare one? Thank you!

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Did you repair it? I have a Unit with the same issue These screens were Factory Flawed, Any Suggestions. for a FIX.
I have a unit with the same problem just not as bad as yours.

I have the same issue on a Korg Karma. Please advise if you ever repaired it. Thanks!

No actual repair, but I found a complete panel from someone for sale, life happened and didn’t have a chance to replace it yet. Perhaps you will have luck and find one too. Or if you find a bare bones unit and move any feature you have over to it. Not sure if there are OEM replacement available and someone to replace it. Good luck.

Can you upload a rear view of the LCD screen please. Want to see numbers, stickers etc …

Little update on my Korg Karma vertical lines. During this last week since I bought this keyboard, I noticed that the vertical lines seemed to be gradually disappearing. I began to use the contrast adjustment to turn the display all the way “black,” and then all the way “white.” I then left the contrast all the way up for an hour, so that the screen was “black.” I bought this synth for a very low price, with the belief/hunch that I could find a way to fix the issue. I get the feeling that this keyboard has just been sitting around turned off for many years, and that the liquid in the display just needed some help getting started. Now, we’ll just have to see if it lasts. Here is a before and after photo.

Great job and good idea! Didn’t know about this technique.

Werner, try the method on the Karma Keyboard in this thread.

Also Check out 283612124749 on EBay.
Hope this helps.

I have a hypothesis. On the back of the LCD controller are several small rectangular boxes soldered to the card. I believe that these are capacitors. I was able to temporarily fix the vertical lines by turning the display contrast all the way up, and then backing off. Over several days, however, the vertical lines returned. I believe that there are some bad capacitors on this card, and that once replaced, this display will work more beautifully than ever. I believe it could be a waste of money to purchase a used Korg display replacement, because it also likely has old capacitors that will fail soon.

Here is a picture of the capacitors. Does anybody know where I can find these? I don’t know what that solid black rectangle graphic is, but so far I’m interpreting one capacitor to read “4.7uF, 25V.” I still need to figure out how to interpret the other smaller one’s numbers, the capacitor on the right. Can anybody assist me in understanding what it says? Something like, “1uF, 500V?”

When I figure this out, I’ll be accepting Korg LE, TR, Rack, and Karma display repair orders. :wink:

Also, I notice that there are the letters “OS” on the top of the capacitors. Or it could say “SO.” But from my research so far, I think it says “OS.” Can anyone tell me what that means?! And where can I find compatible replacements?image

Here’s a photo with the camera backed further away.

Not sure, have you had any luck since your posts? Sorry I have been gone for a while. I was more familiar with the old through hole parts vs smds. Are they electrolytics? Reminds me of the pg-380 Casio guitar issue. The electrolytic smd’s Dried out causing the strings to stop tracking on the synth side. The guitar as a guitar still worked. Is it possible to replace the electrolytics with tantalum capacitors to fix this permanently? My background was more of a builder of kits or from scratch like the Craig Anderton books. Etched board w FCL with etchresist pens etc from scratch vs troubleshooting and fixing. I did buy a complete panel from someone, but haven’t had a chance to replace it or use it. I have the tendency to start to many things and struggle to finish them. Please let me know your current status / progress. Thanks, Andrew

P.S. never tried SMD soldering is a hurdle holding me back as I didn’t want to risk making things worse… when I get a chance I will pull out the unit from the rack and open it up and upload a pic, also of one of the replacement if I do not have to disassemble it further. I never had any luck with these rubber edge connectors like with Casio rack synths and their backlight issues…

Hey there Andrew - okay, here’s an update, as requested. There’s quite a bit of info I’m sharing here, because I couldn’t find it ANYWHERE on the internet. It took LOTS of research to figure it out.

I ended up diagnosing the problem as a faulty connection between the ribbon and PCB gold leads, if that description makes any sense. By squeezing the gold leads with my fingers, I was able to get the lines to go away. Now for an embarrassing admission: I attempted to just barely heat up the leads to solidify their connection to the PCB, and I almost instantly melted the ribbon cable. I had the PCB taped off with painter’s tape, but I didn’t realize that the plastic ribbon is also connected to the gold leads (duh!). I did all of this with the unit powered on, and instantly blew the fuse in the power supply. I’m sharing this so all of the other newbies can learn from me and avoid this idiotic mistake. Here’s the replacement fuse for the power supply that I bought, and it’s working well:

Pack of 5-2.5A Glass Fuse (GMA), 250v, 5mm x 20mm (3/16" X 3/4") Fast Blow (Fast Acting) https://www.amazon.com/dp/B074HFG2P6/ref=cm_sw_r_cp_api_i_4scKEbDAD8S1Z

I still have an interest in building an updated LED display, and I was able to find out from an obscure Russian forum (thanks to Google Translate) that the display is driven by 2 Epson SED1565 drivers/controllers, those 2 little rectangular chips on the ribbon. Just a random piece of info for you.

But, until that awesome day of discovery, I caved and just bought a beautiful used display pulled from a Korg Triton LE from eBay (would have gladly purchased from Syntaur if it had been in stock). It works perfectly. I pulled the glass display out of the black plastic casing and gently inserted it into the Karma’s original white plastic casing. The LED lighting on the Korg Triton LE comes from a single bulb that is dispersed by the design of that black casing. The Korg Karma is much better as it has around 40 small amber colored LED’s on a PCB that light up the display quite evenly. Just know that there’s a little more to it than just plugging in a new display if your new display does not come from a Karma.

I also upgraded the floppy drive to the Gotek SFR1M44-U100K, purchased from AliExpress for $15.

US $15.03 41% Off | SFR1M44-U100K 3.5" 1.44MB 1000 Floppy Disk Drive to USB Emulator Simulation For Musical Keyboard 34pin Floppy Driver Interface

I had purchased new pots for the joystick, but found that DeOxit d5 spray fixed up the originals perfectly for me. Nonetheless, the pots I bought look exactly like the originals. All of the knobs on the Karma use these.

US $4.99 | 1pcs/lot RK11K1140A9L 500 Electronic Tremolo Wheel Potentiometer 4 Pin 103 Speaker Volume Size Adjustment Knob Switch ALPS

The joystick and knobs were very stiff, and several of the buttons required a bit of pressure to get them to respond. I took the entire keyboard apart and sprayed DeOxit d5 (BIG SHOUT OUT TO SAM MIMS!!!) in all of the knobs, buttons, and the joystick potentiometers to get them working again.

I manually adjusted the aftertouch module gain and offset settings to get that feeling much more responsive when I play the keyboard.

All in all, this keyboard plays like a dream, and far better than it did when I first got it. And… the best part is that I got this synth for free, long story. I am thankful to have a keyboard that is FULL of nostalgia for me!!! Here are some pictures of the final product.

I cannot thank Sam Mims enough! I watched all of his videos restoring synths and they motivated me to try it out. It was a basic part swap out and a failed screen repair, but I still came out ahead, so I’m happy. I learned A LOT through the experience. And I read that Sam played keys for Richard Elliot. I’m a sax player and used to listen to his CD’s all the time in high school. So cool.

If you or anybody else figures out how to make a more modern LED display, please share, as I would love to take the upgrades on this synth further!

Also, regarding the capacitor specs:

On my new replacement display, the numbers on that small capacitor are slightly different. My new guess is that the small capacitor spec is “1uF 50V.” And then the number 2 beneath might have something to do with that batch of manufactured capacitors. I really don’t know for sure.


… and

NEAT SETUP You got !!!

Multiple Dittos RNelson4!!!
Thanks so much for the details and success story.

Thanks for the support you guys!

I think you’re right on both counts, SynthNut - yes, I think that they’re electrolytic, and yes, I agree with you that tantalum capacitors would be the way to go in replacing them!