Roland A-88 Mainboard Schematic Request

[neelix136]

Hi.

I need a schematic for the Mainboard of the Roland A-88. [5100029700]

Specified i need the values for R9, R10 & L8.


I broke the USB-Port when the keyboard hit the wall when USB was plugged in. :-(
Thank you very much for any help.


Greetings from Germany

[Jazz P Bass]

Here is a crop of a typical Roland midi port.

Roland Midi Ports.pdf

The IN resistors are 120 & 100 ohm.
The OUT & THRU are 220 ohms.
The Inductors are N1608601T01 made by Maruwa.

N1608Z601T01.pdf

[neelix136]

Thank you for the fast answer.
In this schematics the USB port is not shown.

Maybe someone has an A-88 too and could take a photo of the Board.
As I see it, the resistor values are printed on the parts.

Roland support says that they are not able to tell me the values... A new board would cost around 150€ and thats really disappointing.

The missing parts cost only cents... :-(

[Jazz P Bass]

OOOps.
I had a senior moment.
(Hey give me a break! I just turned 60)
As I was working on a midi controller, I saw your post & thought.....MIDI.
Anyway, try this.

Roland USB.pdf

[neelix136]

60 isn't old. You gained wisdom and now have the time and serenity to enjoy life

Thank you veeeery much, this should help me out. I'll give feedback if I get the mainboard working again. Thank you so much and have a nice day!
I have to do some soldering now

Greetings from Germany

Marcel

[doctor]

60 isn't old. You gained wisdom and now have the time and serenity to enjoy life

Thank you veeeery much, this should help me out. I'll give feedback if I get the mainboard working again. Thank you so much and have a nice day!
I have to do some soldering now

Greetings from Germany

Marcel

Here is the USB port of the A-88.

[Jazz P Bass]

So it appears that R9 & R10 are varistors.

Panasonic Varistor.pdf

[neelix136]

It worked!

R9&R10 should be varistors (for first tryout I didn't replace them at all) and for L8 I just soldered a 0kOhm resistor (as it should just be a bead inductor).

My PC recognized the A-88 again


Thank you so much doctor and and Jazz P Bass!