Kaden wrote:
> Hey... I'm a new guy. For starters, I have to give full props to you
> lot for the ∗outstanding∗ work you're doing in the revitalization of
> the Poly 800. Really, it's a damned amazing community ya have here.
>
> Anyway... I fished a reverse key mk1 out of a dumpster last night;
> took it home, stripped it down, cleaned the remains of what appeared
> to be a burrito off of the keys, keybed and main board, vacuumed out
> the case and blew the boards off with compressed air. Metered the
> onboard battery at 3.23 volts, then put it back together, slotted 6 C
> Cells and fired it up. Up comes 11-p, and it outputs ∗some∗ kinda
> sound... sinish, with swept noise... could be a glitch, coulda been
> intentionally programmed. 20 seconds later the second digit of the
> display goes blank, the first digit dims to 50%, and the controls lock
> up.
My Poly 800 always makes noises that sound a bit like that - tone, noise
and deep VCF modulation - when the memory is corrupted.
It's possible that your batteries are a bit flat. The Poly 800 is a
heavy old beast and will kill ordinary batteries very quickly - get a
set of Duracells or other heavy-duty alkalines. It's worth remembering
that if you use NiCads, the terminal voltage is 1.2 instead of 1.5, so
if were to use them you'd only get 7.2V on the battery! This will
definitely give you problems.
It might be worth removing the battery and shorting across the power
pins of the memory chip for a few seconds to wipe out anything that's in
there. I don't ∗think∗ it maintains much state while the power is off -
it is a pretty simple-minded beast. However, I know that on more
complex synths like my Ensoniq ESQ-1, borked memory contents can cause
all sorts of weird problems.
> Tried the fire up procedure a few more times, learning that there's
> nothing audible from any of the other patches, but the lock-up occurs
> every time 18-20 seconds after power on.
The fact that it works at all suggests that there can't be much wrong
with it. I'd recommend finding a mains PSU to run it from - mine
guzzles batteries. A good power supply will go a long way to helping
you here.
Gordon