Roland XP50 LCD Display Problems

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Valentine10
Posts: 34
Joined: 15:14, 4 February 2015

Re: Roland XP50 LCD Display Problems

Post by Valentine10 »

:-(

I have checked all traces and found one open trace. I've made a bypass and soldered on all remaining caps but still the same problem... I've tried various patches and they all sound very distorted. A piano doesn't sound like a piano etc. Pretty much everything sounds like a broken supersaw waveform :)

I don't think I'll be able to fix this.. maybe it isn't fixable at all.

Grtz, Valentine
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CesarsoundOne
Posts: 203
Joined: 21:29, 9 October 2014

Re: Roland XP50 LCD Display Problems

Post by CesarsoundOne »

I am sorry Valentine, maybe your board has problems in chips too.

Cheers,
Julio.
Valentine10
Posts: 34
Joined: 15:14, 4 February 2015

Re: Roland XP50 LCD Display Problems

Post by Valentine10 »

Well thanks for the help anyway :-)

I've decided to cannibalize my XP-50. If anyone needs parts let me know. I won't charge eBay prices :-) everything works fine except the mainboard.
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CesarsoundOne
Posts: 203
Joined: 21:29, 9 October 2014

Re: Roland XP50 LCD Display Problems

Post by CesarsoundOne »

Good, you can make some money and help someone to repair or restore their XP.
I am holding my XP to sell it to a collector some day, maybe.

Image
roland_xp
Posts: 4
Joined: 21:12, 29 November 2014

Re: Roland XP50 LCD Display Problems

Post by roland_xp »

Hello ! I have a big problem with my keyboard . At the begining, when it startup , after few seconds blocks himself...i mean the software doesn`t respond . I`ve replaced all capacitors on the mainboard with the same values of original caps , all capacitors from power source and now the xp 50 doesn`t stop anymore ...it work perfectly but appears a sound strong distorsion when i press the flaps but not allways just from time to time and not all patches ...for example the tone like "aurora" works fine and some violins. I`ve measured voltages from power source and there are 5,03 volts .... +15,3 volts and -15,4 volts. I`ve made FACTORY TEST and no change. i`ve entered in TEST MODE and results:
CPU....ok
DRAM..ok
SRAM..ok
Battery..3,1 v
all butons respond to comand
bender ..ok
BUT at SOUND test appears L sine and the sound in left speaker is very distorted follows the message Rsquare ...distorted sound in right speaker and after that R/W checking....R/W ..ok i :31 D:36 press enter and out from test mode . What`s mean R/W ok and i:31 D:36 ???what can i do to repair ? please i need help
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CesarsoundOne
Posts: 203
Joined: 21:29, 9 October 2014

Re: Roland XP50 LCD Display Problems

Post by CesarsoundOne »

Roland, my advice is:

The important is to check if copper wires (traces) must have almost zero OHMS (or the beep ringing on the multimeter), specially that ones near the replaced caps, where you find a black spot resulted of leakage of electrolytic on board. If one data bus trace was opened by corrosion, you may have the problems you related. So you can re-make this electric circuit, repairing the trace with a thin wire.

R/W is read / write test on memory or disk.

good luck!
Valentine10
Posts: 34
Joined: 15:14, 4 February 2015

Re: Roland XP50 LCD Display Problems

Post by Valentine10 »

These things sure seem to have a built in self-destruct :-)
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CesarsoundOne
Posts: 203
Joined: 21:29, 9 October 2014

Re: Roland XP50 LCD Display Problems

Post by CesarsoundOne »

Other possbility is that your board has problems with the chips (ICs), like DAC, WAVE DSP, uProcessor, etc. But in this case it is almost impossible to find these chips to buy, because all are obsoleted now :(
roland_xp
Posts: 4
Joined: 21:12, 29 November 2014

Re: Roland XP50 LCD Display Problems

Post by roland_xp »

Thanks for answers, but i think the problem is in ICs because some of them are very hot. The solution may be to replace the mainboard ?
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CesarsoundOne
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Joined: 21:29, 9 October 2014

Re: Roland XP50 LCD Display Problems

Post by CesarsoundOne »

Yes, but it is hard to find too. Maybe you could find a mainboard from an stripped XP50.
mp3ireland2
Posts: 30
Joined: 16:47, 11 January 2016

Re: Roland XP50 LCD Display Problems

Post by mp3ireland2 »

Hi all,
I got a Roland Xp-50 from a pawn shop.
The sound wasn't clear so i left it into a repair shop, they said that the transformer was hanging off the pcb and an inductor/capacitor was burnt out. The jobsheet wasn't with it so that's the only info i got!
IT was working fine anyway, sounded great when I put the "keyboards of 60's and 70's" in it.

I was getting a battery low warning though, so decided to open up to change the CR2032 battery, whilst open i also removed the floppy drive and put a usb floppy emulator in. I noticed before removing the floppy drive that the power wasnt plugged into it.

I put it back together and when i turned it on i got a line of black rectangles on top line of the LCD.
Nothing will respond and no sound comes out.
I opened it up again disconnected the emulator and put the old battery back in.
I noticed my expansion card was now loose (hadn't seen the clip in things you turn to secure it. I tightened that too.

That's all the info I can provide! I suspect it's additional capacitors that now need to be replaced, but it's hard to find people who experienced the line of black squares across the top of the LCD.

Bringing it back to the shop I think as I can't do anything with it, but before i do, anybody got any ideas?
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CesarsoundOne
Posts: 203
Joined: 21:29, 9 October 2014

Re: Roland XP50 LCD Display Problems

Post by CesarsoundOne »

it is a symptom of short circuit on data or address bus of CPU (microprocessor). Or some voltage regulator is not working (check the voltage on CPU and other important ICs, to see if there is the +5v). Or the worst, the CPU was killed.
mp3ireland2
Posts: 30
Joined: 16:47, 11 January 2016

Re: Roland XP50 LCD Display Problems

Post by mp3ireland2 »

Thanks for the reply, hopefully it can be fixed :-o
mp3ireland2
Posts: 30
Joined: 16:47, 11 January 2016

Re: Roland XP50 LCD Display Problems

Post by mp3ireland2 »

It got fixed anyway, i installed the floppy emulator the wrong way it seems :-( and messed up the power supply.

I had no back up (although just bought the synth so hadn't many personalised sounds).

Is there anywhere i can download the original factory settings? Or better still has anybody a back up that they could email me with some nice sounds? Or where can i download patches for the xp-50 for free? I changed the battery and lost everything so not sure how bad things will be! Won't get to try it out till this evening.

Any help appreciated!

Thanks,
Chris
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CesarsoundOne
Posts: 203
Joined: 21:29, 9 October 2014

Re: Roland XP50 LCD Display Problems

Post by CesarsoundOne »

mp3ireland2 wrote:It got fixed anyway, i installed the floppy emulator the wrong way it seems :-( and messed up the power supply.

I had no back up (although just bought the synth so hadn't many personalised sounds).

Is there anywhere i can download the original factory settings? Or better still has anybody a back up that they could email me with some nice sounds? Or where can i download patches for the xp-50 for free? I changed the battery and lost everything so not sure how bad things will be! Won't get to try it out till this evening.

Any help appreciated!

Thanks,
Chris
You should restore the XP to the factory settings that everything will return back. Attached is the procedure.

Also, you may find nice free sounds here:

http://www.nathansheldon.com/xp-80/patches.html

CesarSound.
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