Search found 1446 matches

by Mooger5
Fri Apr 26, 2019 9:19 am
Forum: HELP!
Topic: DX100 keys not working
Replies: 10
Views: 2737

Re: Corrosion beneath solder mask

I think that they use graphite for making contact because if they have used copper, the keys could cause double triggering. In the past I have used caikote 44 which is very conductive , and I experienced the double triggering problem. Anyways, i am glad you did not follow my advice and got it sorte...
by Mooger5
Fri Apr 26, 2019 9:15 am
Forum: HELP!
Topic: DX100 keys not working
Replies: 10
Views: 2737

Re: Corrosion beneath solder mask

After I solve the issue, I'll inspect the actual keys. Because I now suspect it's a mechanical failure. The original carbon in the rubber strip appears fine, so the thicker conductive paint is probably just shortening the distance between the strip and PCB. It could be the plastic "hammers" that pre...
by Mooger5
Fri Apr 26, 2019 8:51 am
Forum: HELP!
Topic: DX100 keys not working
Replies: 10
Views: 2737

Re: Corrosion beneath solder mask

OK, after that I decided to apply a thicker layer of conductive paint to the strip and all the keys worked, but then the B and C of the third octave didn´t work at all. Disassembled the thing once more, cleaned the contacts, reassembled. Now the same keys and another one start to work immediately up...
by Mooger5
Fri Apr 26, 2019 7:46 am
Forum: HELP!
Topic: DX100 keys not working
Replies: 10
Views: 2737

Re: Corrosion beneath solder mask

Fiddly is the correct word! Glad I did some more readings: the PCB contacts actually measure well: around 50R. You can see they put the carbon layer on top of existing copper tracks, so it´s only to prevent oxidation? I also scraped the solder mask to expose a little copper and verified continuity t...
by Mooger5
Fri Apr 26, 2019 7:28 am
Forum: HELP!
Topic: Dx11 or Dx21 Quandary
Replies: 4
Views: 2011

Re: Dx11 or Dx21 Quandary

Same engine as well.
by Mooger5
Thu Apr 25, 2019 11:45 am
Forum: HELP!
Topic: DX100 keys not working
Replies: 10
Views: 2737

Re: Corrosion beneath solder mask

Hi Yekuku

Thanks for your advice!

The PCB contacts wearing out makes much more sense :)

I'll try with DIY conductive paint and a fine brush instead oficial aerosols, as it's more practical to apply on such small areas. I can control the thickness of the layer so that it doesn't spread.
by Mooger5
Thu Apr 25, 2019 12:29 am
Forum: HELP!
Topic: DX100 keys not working
Replies: 10
Views: 2737

DX100 keys not working

Case in point: my recently purchased DX100 after several failed attempts at repairing the keyboard contacts. Cleaned the pads, cleaned the conductive strip, applied graphite with acrylic based ink, nada. Always the same keys that need too much pressure to work. The copper traces on the PCB look odd....
by Mooger5
Thu Apr 18, 2019 7:47 pm
Forum: HELP!
Topic: Korg Poly-800 not working
Replies: 37
Views: 9031

Re: Korg Poly-800 not working

Hey crafter. Well done for not giving up. That was a great find. You said the board had been scavanged, that there were some components missing which had to be replaced. Now that's a zero ohm resistor iow a jumper. Maybe whoever tried to fix the synth had found some "funny resistors that were shorte...
by Mooger5
Tue Apr 16, 2019 11:27 am
Forum: HELP!
Topic: Korg Poly-800 not working
Replies: 37
Views: 9031

Re: Korg Poly-800 not working

What. Not even the display? IIRC I had had ran out of ideas. On that site they managed to fix the synth only by loading up the patches via audio file. Curiously the service manual hints at that. Maybe something in the code. That was after they threw everything at it. Try that even without the displa...
by Mooger5
Tue Apr 16, 2019 10:33 am
Forum: General Synthesizers
Topic: SIX-TRAK battery replacement and still presets will not save
Replies: 8
Views: 2462

Re: SIX-TRAK battery replacement and still presets will not

Suggestions:
Measure the battery voltage.
Look for damaged copper tracks.
Replace RAM chip.
There should be a small capacitor across the battery. If leaky, replace with same value tantalum.
by Mooger5
Mon Apr 15, 2019 9:04 am
Forum: General Synthesizers
Topic: SIX-TRAK battery replacement and still presets will not save
Replies: 8
Views: 2462

Re: SIX-TRAK battery replacement and still presets will not

There is an old thread in this forum. Same problem, marked as 'solved'. There was also a mod for the battery to prevent it from discharging fast due to an early design error.

Good luck.
by Mooger5
Thu Apr 11, 2019 11:15 pm
Forum: General Synthesizers
Topic: Roland SH101 - "rare white colour model"
Replies: 9
Views: 3584

Re: Roland SH101 - "rare white colour model"

viewtopic.php?p=383491#p383491

And, these are only minor quibbles, nothing really important. Youngsters will always have their own slightly distorted version of history.
by Mooger5
Thu Apr 11, 2019 10:48 pm
Forum: General Synthesizers
Topic: Roland SH101 - "rare white colour model"
Replies: 9
Views: 3584

Re: Roland SH101 - "rare white colour model"

Exactly. These new employees are the same who revealed that the 106 hpf added a bass boost in the lowest setting like it was some big news when imo they read it here first in this forum. They seem to also claim the tr7x7 is 12 bit when it´s 8 bit. The white 101 they saw was most probably by customsy...
by Mooger5
Thu Apr 11, 2019 8:01 pm
Forum: General Synthesizers
Topic: Roland SH101 - "rare white colour model"
Replies: 9
Views: 3584

Re: Roland SH101 - "rare white colour model"

Present Roland´s employees... I think they would probably say there was a white Jen SX1000 too.
by Mooger5
Sat Apr 06, 2019 11:36 am
Forum: HELP!
Topic: EMU ESI-32 crackling sound and distorted playback
Replies: 12
Views: 3165

Re: EMU ESI-32 crackling sound and distorted playback

Forst try as sandwich says.
Sometimes pcs can be fixed that way. I'd try one ram module in slot 1 then in slot 2 at a time.
It will be a relief if that fixes it as theres no sign of a service manual.