Vintage Synth Repair

--- In vintagesynthrepair@yahoogroups.com, "Roy J. Tellason" 
<rtellason@...> wrote:
>
> On Tuesday 01 April 2008 08:04, Scott wrote:
> > --- In vintagesynthrepair@yahoogroups.com, "fsimon100" 
<fsimon001@>
> >
> > wrote:
> > > Hi,
> > > I just joined. I found three nonworking synths and bought them 
for
> > > $30 each. A Prophet 10, Korg Trident mk II, and Roland Super JX 
10.
> > > 1)The Prophet has some regulators in wrong. The 12v and 5V were
> > > backwards but the 12V should have been fixed voltage and had a
> > > varible regulator instead of fixed Vreg without feedback 
resistors.
> > > Hopefully that fixes that. There may have been some big voltage 
on
> > > the 5V circuit. I'm a little concerned because that reg open 
loop may
> > > have been 37v. It lit up though while wrong just no sound.
> > > 2)The Korg had a memory battery leak on the board and fried some
> > > traces. So PCB repair and new battery may fix that. I like my 
odds on
> > > this one. It lit up too but no sound.
> > > 3) The Roland has good Power supply but nothing lights up. The 
whole
> > > top LCD or LED plus all the buttons are out. I could appreciate
> > > advice or if anyone has a schematic would help. If I get one 
synth
> > > working I made a good purchase. I'm optimistic on the first 
two. They
> > > light up and look like they want to work.
> > >
> > > Thanks,
> > > Frank
> > >
> > > I'll talk about my Hammond H-100 problems later.
> >
> > I have Hammond H-100 parts
> 
> I have a couple or three loose-leaf binders full of Hammond stuff I 
haven't 
> even looked at yet.  What kinda parts do you have?  It's been so 
long since I 
> did much work on Organs (probably stopped around 1985 or so) I 
don't even 
> remember the H-100...
> 
> -- 
> Member of the toughest, meanest, deadliest, most unrelenting -- and
> ablest -- form of life in this section of space,  a critter that can
> be killed but can't be tamed.  --Robert A. Heinlein, "The Puppet 
Masters"
> -
> Information is more dangerous than cannon to a society ruled by 
lies. --James 
> M Dakin
>
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H-100
My preset keys won't stay engauged. How do you disassemble to get 
underneath keys. Also I have low volume if I hold them down manually. 
I know tube outputs are good but not sure where the low signal is.