[sdiy] Kurzweil K2000 Query continued

[Dave Kendall]

On boot-up the display will show a fancy LCD screen with "V.A.S.T." and 
the soft/hardware revision will be  displayed on the bottom  of the 
LCD. E.G. V3.87J
  C = Calvin , J = Janis. Calvin PCBs were the earlier versions, and 
IIRC, had a few minor problems that the J boards ironed out.

It's likely to be running version three. V3.87 was the last version I 
am aware of, and sped up the SCSI load function amongst other things, 
although it is slightly more buggy than the previous V3.54. Earlier 
versions have V3.01. I don't think I've ever seen a V2, as V3 did so 
much for it, so all the ones I've used/seen were V3s...

I know it sounds silly, but did you try cleaning the battery contacts 
and putting new batteries in? despite the previous owner *not* having 
had batteries in it....

Only reason I mention this, is that a faulty battery connector (with 
new batteries) caused my K2000RS V3.87J to repeatedly crash on boot-up. 
Cleaning the contacts and 2-pin pcb connector, and using 3 fresh AA 
cells cured the problem *permanently* much to the surprise of myself 
and the folks on the sonikmatter K2000 forum with whom I was discussing 
it. It didn't make sense to them either, but hey, it's still working 
faultlessly, and that was *all* I did  to it........ Apologies if 
you've been there already :-)

FWIW, the failure of an output transistor on output D (right) 
manifested itself as a high pitched whine in my old K2000 rack. (a 
V3.54J at that time) It was a known common failure back then ('96 or 
so).

I did find a link a while back about a viable replacement LCD display 
for the K2000. Mine, like all of them it seems, has an increasingly 
faded LCD backlight with use/age.  If you take it apart for servicing, 
then that is well worth doing.  It will most likely fade to almost 
illegibility eventually - I'm hanging on due to lack of money, but soon 
it will *have* to be replaced - I could barely read it at the last 
gig.......

Also, take care that all the buttons move freely up and down when the 
case is reassembled. A stuck key will be scanned by the processor on 
boot-up as "down" which affects the running of the machine afterwards - 
some functions will then not work (in my case, the "enter" key - not 
good!).

Hope you get it fixed. I'll dig out the details of the alternative 
replacement LCD if you are interested.

cheers,
Dave
(owner of a faded K2000)


On Jul 14, 2009, at 05:44, DTK wrote:

> Thanks for all the suggestions so far.  I've done soft and hard 
> resets, to
> no avail, so its time to start looking at hardware issues.  Yay.
>
> The protection FETs sound like a good bet... but I'm not sure they fit 
> the
> symptoms.  If I understand, a failure there would result in no sound 
> being
> output.  Or, is there a possibility that they could be partially 
> activated,
> reducing the output level?
>
> I guess its a moot point until I open it up anyway.  BTW, is there any 
> way
> to tell if I'm dealing with a Calvin before I open it up?
>
> Thanks for all the help, I'm sure I'll be back for more :)
>
> DTK
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