Roland RD-700GX Service Notes request - service manual

[ivanhoe]

Hi,

My Roland RD-700GX doesn't start up...there is just ROLAND on the screen.

In the update mode, there is no updating...just UPDATE MODE:

LEDs are not working, nothing.

I hope that the "Switching regulator" is not working correctly (less expensive I suppose). I've measured 5,14V that shoudl be OK for 5V, but I am not sure for 14,72V...strange as I've thought that it should be 12V for new electronics (not as before with the old one and 15V).

Could be that the "Mother board assy" is under the question : boot loader or whatever. How to check it without the service notes and knowhow to do it?

If someone can help it will be great. I can give you more details and even if someone needs it I've found the service notes for the RD-700sx.

Cheers,

[Jazz P Bass]

Roland RD-700GX Service Manual

Here is the service manual.
It is a start

[ivanhoe]

Roland RD-700GX Service Manual

Hi,

Thank you for helping and support

Now I have the RD700SX (previous to GX) and the RD700 (the first version version). Still missing the RD-700GX service notes.

I still have this question about this 12 & 15V difference.

Please find the picture of how it is.

Cheers

[Jazz P Bass]

I would be concerned about the 3.3 volt rail & the 5 volt rail.
According to the schematic they are independant regulators.

[doctor]

I would be concerned about the 3.3 volt rail & the 5 volt rail.
According to the schematic they are independant regulators.

If “ROLAND” inscription presents on the display, both 3.3V and 5V supply voltages
are intact. It is not necessary to check. ± 15V voltages (as well as 3.3V and 5V)
should be in margin ±5%. For this reason 14.72 V is ok.

Try to check whether one of the auxiliary boards (besides main board) is out of order
- one of them may prevent correct loading and activation process.

Turn device off and carefully disconnect the following connectors from the main board:
CN8 (Panel-L board), CN26 (Encoder board), CN23 (Panel-R board), CN9 and CN33 (SRX base board).
CN9 and CN33 are the same, for this reason mark related harnesses so as not confuse.

Turn device on. If you see correct loading process and normal final display readout, one of the boards is out of order. Detect defective board by connection one connector at a time. Needless to say that each connection/disconnection action should be perform only when the device is turned off.

If it was to no avail, it’s likely flash memory is out of order and main board should be replaced.

[ivanhoe]

Thanks

Hi,

Thank you

I've tried something similar with mother board connectors, didn't work, but I'll try again in order as you've well described and will be back tomorrow with news.

Best regards from Paris!

Cheers,

[ivanhoe]

by the way, those 14.72V...I've thought it should be 12V +-5% = 11.4V to 12.6V !!! 14,72 is much higher, maybe there is some anti-surge protection?!

cheers

[doctor]

by the way, those 14.72V...I've thought it should be 12V +-5% = 11.4V to 12.6V !!! 14,72 is much higher, maybe there is some anti-surge protection?!

cheers

This device has separate power supply having ± 15V and +5V voltages
(check connector CN15 pin 1:+15V, Pin 2: AGND, pin 3: -15V,
pin 4: +5V, pin 5: +5V, pin6 GND, pin 7: GND)

[ivanhoe]

+-15V

THANK YOU

you're right as I've just received the confirmation from Roland that there are 2x5V and +15 and -15.

They have told me that the polarity is important but without the suggestion if it concerns the break down like this or not.

I'll check it again but I have 2x5V and 2x+15V, no -15?!

I'll check also the mother board as You've suggested.





For those who needs it please find the schema from Roland

Cheers,

Ivan

[g1]

You need to get your -15V supply sorted out before doing any other checks with boards.

[doctor]

You need to get your -15V supply sorted out before doing any other checks with boards.

First of all you need correct supply voltages.

First opportunity is to repair switchable power supply.
It’s possible, but it is not a job for the faint hearted.

Second opportunity is to purchase new power supply from
Roland (p/n 03782334).

Third opportunity: look name of a power supply manufacturer
(power supply’s p/n A1DU2L3B184) and address to his French distributor.

Do not forget that you may (not necessarily) face additional challenges
caused by applying incorrect voltage.
This damage may be larger than new power supply price.

Good luck,

[ivanhoe]

AFTER the testing

Hi,

I'am back at home and immediatly I've done some test as indicated, so:

1) power supply should be OK as there are 2 x 5.14V, +14.86V and -14.52V ( I've followed you description thanks)

2) "Turn device off and carefully disconnect the following connectors from the main board:
CN8 (Panel-L board), CN26 (Encoder board), CN23 (Panel-R board), CN9 and CN33 (SRX base board)".

power on = ROLAND on the screen!

so up to you it’s likely flash memory out of order and main board should be replaced

- Do you know the reference, please, and what the cost it can be?

- Does the spare part mother board has the programmed flash in order to get it just for "plag'N'play" from Roland stock or something else is needed (programing tool, special USB etc.)?

- Does the reparation of the mother board/flash memory could be possible = less cost?

Thank you for everithing, at least it was pleasure to try the diagnostics and comunicate on the forum with you

Cheers

[ivanhoe]

Assy 73789378

hi

I've found something like réf. ASSY : 73789378 on the board itself

cheers

[g1]

Hi,

I'am back at home and immediatly I've done some test as indicated, so:

1) power supply should be OK as there are 2 x 5.14V, +14.86V and -14.52V ( I've followed you description thanks)

2) "Turn device off and carefully disconnect the following connectors from the main board:
CN8 (Panel-L board), CN26 (Encoder board), CN23 (Panel-R board), CN9 and CN33 (SRX base board)".

power on = ROLAND on the screen!

so up to you it’s likely flash memory out of order and main board should be replaced

This is NOT what he said. You did not reconnect the other boards one at a time to see which board is causing the problem. Go back and reread. One of the other boards is likely the problem.

[doctor]

This is NOT what he said. You did not reconnect the other boards one at a time to see which board is causing the problem. Go back and reread. One of the other boards is likely the problem.

I think that the best way for you – address to the Roland authorized service.

The reasons are the followings:

1. I’m not sure that you did everything right.
2. In any way, repair such complicated device up to single part level
in line with Internet recommendations is almost “mission impossible”.
Even having the service manual.
3. I’m not sure that Roland sends spare parts to general customer
(but you can try to send request on price estimate for Main Board
Assy p/n 73789378).

Good luck,