Sequential circuits samplers

Well, I might be making some progress.  There's a "buffer" chip, a 7406,
that's identified as U201.  It sits between the floppy controller and
the header P202.  On two of the hex inverted pairs they don't seem to
be inverting the signals.  Namely, pins 1/2 and 3/4.

Does anyone have a clean copy of the schematics?  I'm having a hard
time ready what each of the pins do on the online version.  This is
on what appears to be drawing SD 2000-2.

This is a very inexpensive part, so I might just pull it, socket
a new one, and try.

Rob

Henrik wrote:
> Same problem here too.  
> 
> --- On Thu, 10/8/09, j. aaron <tomkah@...> wrote:
> 
> From: j. aaron <tomkah@...>
> Subject: Re: [prophet2000] Re: Nothing but "nd"
> To: prophet2000@yahoogroups.com
> Date: Thursday, October 8, 2009, 10:51 PM
> 
> 
> 
> 
> 
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>  
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> 
> 
>     
>                   ive experienced this same problem
> 
> the original 2002 drive died, so i picked up a suitable replacement on ebay
> 
> making sure the jumpers were correctly aligned
> 
> same thing, ...drive powers up, disc takes a spin and then 'nd'
> 
> since that drive only cost me $10, i decided id try buying another
> 
> suitable replacement off ebay (different model than the first), that i also jumper configured correctly and got the the same result ...'nd'
> 
> i tried switching things around a bit but sort of gave up on it at that point
> 
> im still over $40 ahead of the $70 whine country wanted for a new one,
> 
> so i figured eventually ill try getting another one off ebay sometime
> 
> and repeat the process, but i really couldnt find a reason why those drives werent functioning
> 
> this discussion has rekindled my interest in getting  my 2002 going again
> 
> i put a ton of work into sampling back in the late 80's/early 90's
> 
> and id like to revisit some of those sounds 
> 
> ...heres hoping help arrives!
> 
> -yeller
> 
> 
> 
> --- On Thu, 10/8/09, Rob Miller <dpc318@sbcglobal. net> wrote:
> 
> 
> 
>> From: Rob Miller <dpc318@sbcglobal. net>
> 
>> Subject: Re: [prophet2000] Re: Nothing but "nd"
> 
>> To: prophet2000@ yahoogroups. com
> 
>> Date: Thursday, October 8, 2009, 12:06 PM
> 
>> I didn't change the jumper on the
> 
>> factory drive that selects DS0, and 
> 
>> the replacement from WC doesn't have any.  The power
> 
>> cord has to flip
> 
>> between the stock and the replacement (and the
> 
>> replacement  instructions
> 
>> indicate so).  I have flipped back and forth the data
> 
>> cable, since there
> 
>> is no real keying to it.
> 
>> I hope  it's not the driver chip.  I can replace
> 
>> it, but it should would
> 
>> be easier not to. The drive spins up on power up, but
> 
>> doesn't seem to
> 
>> seek when I try to move data to/from it.
> 
> 
>> I'll keep poking around and see if I can get the right
> 
>> combo working 
> 
>> now.  I appreciate the forum's help!
> 
>> Rob
> 
> 
>> duncan wrote:
> 
>>> have you got the jumpers in the right place on the
> 
>> drives? I hope when you say "flipped" you don't mean
> 
>> "reversed".. .. I killed a floppy drive doing this by
> 
>> accident.
> 
>>> the floppy disc driver chip is fairly standard, I
> 
>> think, but would be a tricky job to replace....
> 
> 
>>> I have the boards from my 2000, which had a dead
> 
>> keyboard controller (which WC couldn't help with- it was a
> 
>> custom IC)... let me see if I can locate anything useful on
> 
>> them for you, & let me know how you get on. I have to
> 
>> strip some bits off them for another forum member whose
> 
>> patience must be running out by now.... :-/ I've been a bit
> 
>> busy this year....
> 
> 
>>> --- In prophet2000@ yahoogroups. com,
> 
>> Rob Miller <dpc318@...> wrote:
> 
>>>> I'm hoping I can get some help here....
> 
> 
>>>> My 2000 is now running 4.3b with a brand new
> 
>> drive...but it STILL
> 
>>>> gives me "nd" (no disk) whenever I try to do
> 
>> anything with the
> 
>>>> drive.  I can't read factory disks on power
> 
>> up, nor can I load
> 
>>>> single sounds, and I can't format a disk.  I
> 
>> get the same "nd"
> 
>>>> every time.
> 
> 
>>>> I've flipped the drive cable, and now have two
> 
>> drives (original
> 
>>>> and WineCountry new one) and they perform the
> 
>> same.
> 
> 
>>>> Rob
> 
> 
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> 
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>> ------------ --------- --------- ------
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> 
>> Yahoo! Groups Links
> 
> 
> 
>>     mailto:prophet2000- fullfeatured@ yahoogroups. com
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