May have smoked the main board on my JV-30

[spiderfish]

The LCD display on my Roland JV-30 went blank awhile back. I've had the keyboard for about 20 years and have never changed the backup battery, so figured it would be a good place to start. I took the back off the keyborad and unscrewed the main board to gain access to the battery, swapped it out for a fresh one, and put it all back together. I didn't use a static discharge leash, as I didn't really touch anything other than the battery and tried to make sure I was touching the metal chasis at all times while swapping it out. Anyhow, the entire process was quick and painless, and when I fired the unit back up the display was working great again. However now the pitch bend doesn't work and I can't get a midi out signal into my daw. The audio outputs on the keyboard work fine, evrything else seems to be working good, just the midi and pitch bend is dead (and the vibrato, which I assume works off the same circuitry as the pitch bend). I suspect damage to the mainboard due to static electricity, it's all I can think of that may have happened. Any thoughts?

 

[Steenamaroo]

Hi,
It can happen but it's not all that common.

I don't know the particular keyboard but I'd guess it's more likely that you've disturbed a ribbon or molex connector.
Does that sound plausible?

 

[spiderfish]

I was thinking the same thing, so I took it apart again and checked all the ribbon connections to the mainboard to make sure nothing got inavertently disconnected or was loose. No luck, still have the same issues. I initialized the system to factory default in the hopes that it would maybe do the trick but no dice. I have checked the midi transmit settings to make sure it wasn't simply a setting that got changed, and also re-checked the available settings on my interface (Presonus AudioBox 22VSL). I'm at a bit of a loss...

Kind of disappointing, its an old synth but been with me for a lot of years and still used it quite a bit as a controller for my VST's.

 

[spiderfish]

Hey, thanks for the link to the service manual above. I put the keyboard into service mode and ran the midi test as indicated in the link, the midi tested ok. I also pulled the battery and left it out over night and stuck it back in but no change. I checked the midi in and it is working fine, its just the midi out that is dead. Not looking good...

 

[YanKleber]

Hey, thanks for the link to the service manual above. I put the keyboard into service mode and ran the midi test as indicated in the link, the midi tested ok. I also pulled the battery and left it out over night and stuck it back in but no change. I checked the midi in and it is working fine, its just the midi out that is dead. Not looking good...

Not a big keyboard 'conneceur' here but I have an extensive experience with electronics/digital stuff. It really doesn't seem to me that you have burned anything with static electricity. I worked as a computer technician for years and have opened and performed small services in a bunch of my electronic gadgets in the latest 30 years and never (ever!) had something smoked just for touch them. Maybe I am just a lucky bastard but what I don't think that electronic stuff doesn't burn as easy like this.

Anyway, in my opinion it seems more like that when you replaced the battery it was time enough unpowered to disconfigure/desactivate something regarding to the MIDI. Did you try the procedure described at manual to reset the unit completely to the factory defaults?

Stupid question (and depending on the answer it MAY have burned out something): are you sure that you replace the old battery with the right type of battery (same voltage)?