[sdiy] Help! Fatman problems!

[matti]

first thing to check is that the Gate and MIDI lights respond...if not,
check the CPU circuitry.

then check that your output and ADSR settings are right to hear sound  :
sustain all the way up, output all the way up, ADSR all the way up.

then check that the filter cutoff is all the way up.

other than that....take a fine-toothed comb and look for nits. patiently.
an easy place to start is to check the polarities on all the polarised
components : caps, ICs, transistors. Go on to check the values of all the
resistors, mark them off (use the assmbely manual...) as you go along.
THis includes the front panel knobs and their orientations. It's semi-easy
to get them reversed. Then, get out your reading glasses or loupe if you
need them, and check for solder bridges. on BOTH sides ofthe PCB. My
fatman wouldn't work for nearly a _year_ before I flipped the thing over
and noticed a solder bridge under the DAC. :(.

of course, there are whole books devoted to troubleshooting curcitry...

if that fails, repeatedly, you've lost hope....un-lose that hope. Being
able to enjoy synth-diy has a lot do to with believing that you _can_
infact do it. if given some practice. Contact PAIA if you can't get it to
work, they ca give you troubleshooting help, or repair it for a nominal
fee.

enjoy


On Fri, 18 Jan 2002, Moho Disco wrote:

> Funny, I had this exact same problem when I turned my
> Fatman on...  and I haven't gotten around to trying to fix
> it yet either, so if anybody knows the answer...
>
> Lava
>
> At 09:56 PM 1/18/2002 +0000, John Goodall wrote:
> >Hi everyone,
> >
> >I've just plugged in my Paia Fatman having finished construction of it to
> >discover it doesn't work :0(
> >(It was to be expected really, it's the 1st synth I've built)
> >
> >Here's the problem. When I strike a key I get a very short noise coming out
> >but it's very brief and to my electronically untrained ear sounds like it
> >could be a really low bass note, maybe just 1 cycle of the waveform(?).
> >
> >Playing a higher or lower note on the keyboard makes no noticeable
> >difference to the pitch, neither does changing any of the 5 trimmer
> >resistors or the pitch control on the front.
> >
> >The 1800 ohm resistor that bridges R34(1) & R34(3) was missing from the kit
> >so I ordered one from RS, it's the same value but states it is 1% (R5%).
> >I've also used a blue led for the power light, I know these use slightly
> >more current but that couldn't be the problem could it..?
> >
> >Please can someone help me? It would be great if you could advise me in
> >simple terms, I am a total novice!
> >
> >Many thanks, John
> >
> >
> >Visit our website at http://www.rm.com
> >
> >Standard Disclaimer:This message is confidential.  You should not copy it or
> >disclose its contents to anyone.  You may use and apply the information only
> >for the intended purpose.  Internet communications are not secure and
> >therefore RM does not accept legal responsibility for the contents of this
> >message.  Any views or opinions presented are only those of the author and
> >not those of RM.  If this email has come to you in error please delete it
> >and any attachments.  Please note that RM may intercept incoming and
> >outgoing e-mail communications.
>

-
you stupid vulgar greedy american death-sucker
some trillions of years ago a sloppy dirty giant flicked grease
from his fingers
one of those gobs of grease is our universe on the way to the floor
*splat*