Roland JV-30 Schematic

[SeattlePilgrim]

Looking for schematic as a 9.5VAC power supply was accidentally plugged into the 9VDC input! Thanks.

[doctor]

Looking for schematic as a 9.5VAC power supply was accidentally plugged into the 9VDC input! Thanks.

First of all check that JV-30 internal power supply is OK:

1.Whether D5 is shorted. If not ↓

2.5VDC exists on IC20 pin 5. If yes ↓

3.+12V exists on IC26 pin 1 and -12V exists on IC27 pin 3.

[SeattlePilgrim]

Thanks, looks like it is D5 shorted!

[SPARESROLAND]

I can email you a pdf copy of the service notes if you email steve.barrett@roland.co.uk very best regards
steve

[Mr.Maggoo]

I've got a blowed up Jv-30 also.
I contacted the Roland repair in Vancouver, Canada and he was nice enough to send me the schematic of the power supply section of the keyboard. So now you can have it too.

Take a look for the 9 Volt and 5 volt section. If you have 9 and 5 volts, then take a look at the section that transforms the +9 volts to + & - 12 volts. It is driven by a crystal clock and then a "ladder" circuit to boost the voltage up high enough for the voltage regulators to work.

http://i574.photobucket.com/albums/s...PLYCIRCUIT.jpg

[Mr.Maggoo]

Do you have a spare "main board" for the Roland JV-30 that you could sell?
I'm just about to go pick it up from the roland repair depot. I paid $40 for the diagnose/possible repair session. They said it would cost more to repair than the $40, but they don't know how much more. It definitely needs a new MAIN Board, and I'll not interested in spending very much more for this keyboard. It could be a bad CPU at this point.