[sdiy] Disassembling MKS-70 Power Supply
sounddoctorin at imt.net
Mon Nov 3 21:38:52 CET 2008
Well...two JX8P's actually. The JX10 has the same two JX8P boards in it
but the MIDI is totally silly. You can only do bulk dumps from a
CARD!...for example. The MKS70 has much better MIDI implementation. -Bob
Csaba Zvekan wrote:
> Thanks, Bob.
> That's exactly what it was . It wasn't hard to get to the board
> either. If you think they put two Roland JX-10s in a 3 HE Rack mount
> unit. That's pretty cool :)
> So I put some flux on the regulator solder joints and added fresh
> solder . I should have desoldered and removed the old tin and
> cleaned pads. I was thinking of that later. Oh , well it works now
> under several hours of testing it seems fine.
> I have ordered some 6800uF and 4700uF that I want to replace them as
> well. They took a lot of beating over the last 20 years, I assume.
> When I open up the unit again for that I will sure remove the old tin
> and clean pads etc.
> Again thanks for the hint, it was very helpful.
> On Nov 3, 2008, at 7:13 AM, Bob Weigel wrote:
>> I don't recall off the top the circuit details but common problems
>> are regulator solder joints on those. If it shuts off after a few
>> seconds that MIGHT be the problem.. On the other hand could be some
>> leaking electrolytic or something. But you have to pull a few
>> things out as I recall to get that board out. Get under there and
>> verify the solder before you go to a lot of research time though and
>> I'll bet you'll find the problem. If you have an esr meter it's nice
>> to check the caps. -Bob
>> Csaba Zvekan wrote:
>>> Hi Group,
>>> My Roland MKS-70 (SUPER JX) 's power supply is failing . After two
>>> seconds it shuts off. I am suspecting capacitors on the power
>>> supply board. Can anybody tell me an easy way to get to it. Before
>>> I make some stupid mistakes?
>>> It looks like I have to loosen the VOICE boards that are on hinges
>>> , right ?
>>> I googled the MKS series and they seem to be a bit flaky in age.
>>> Also maybe one of you knows already the problem. What's the deal
>>> with the sensing in the circuit ?
>>> Any help greatly appreciated
>>> Synth-diy mailing list
>>> Synth-diy at dropmix.xs4all.nl
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