[sdiy] Polysix Repair - Panel/Ground Electrified!?

Ian Michael Ferguson ifergu1 at gmail.com
Fri Jul 21 04:29:06 CEST 2017


Thanks everybody for your input.

Yes, when you disconnect from the filter board, only the transformer
connects to the case via a lug on the chassis.

I got a receptacle tester at the hardware store and the socket tests just
fine.

I'm not sure what the deal is, but I got home tonight and plugged it in,
expecting to have the electrification return, but it's not there!
Even tried rotating the plug 180 in case that was it, but no change.
I really did nothing different but go to bed, go to work, and come home 🤔

Anyway, I plugged the filter board/rest of the synth in, hoping it would
work, but it's the same as I describe earlier.
All LEDs seem operational. When on a memory slot there is a droning sound,
which is affected by the volume control, pitch wheels, and *influenced* by
keys, but nothing else.
Manual mode does nothing. I suppose my main board still needs work, or the
work was fine just one or more of the chips are bad?

I can see that pressing keys activates the weird axial LEDs on the voice
board, even though nothing comes out...

On Thu, Jul 20, 2017 at 4:45 PM, <rsdio at audiobanshee.com> wrote:

> On Jul 20, 2017, at 9:12 AM, Ian Michael Ferguson <ifergu1 at gmail.com>
> wrote:
> > It also only has a two-prong, non-polarized plug.
>
> It seems dangerous to have the cord connected to the case with a
> non-polarized plug - or did you say that only the transformer connects to
> the case?
>
> Be very careful, but try reversing the plug - flipping it 180 degrees.
> I've seen electro-mechanical clocks that would literally count time
> backwards when the plug was reversed. I'm not familiar with the Polysix,
> but if you're getting a shock from the panel then I'd be curious to see if
> it goes away when you reverse the plug.
>
> If this were my Polysix then, apart from reviewing the schematics, I'd be
> almost certain to replace the two-prong cord with a three-prong cord so
> that the panel ground lug could be disconnected from both the Neutral and
> Hot wires. I'd rather see only the third ground prong connected to the
> chassis, because there's no guarantee that a non-polarized plug will be
> inserted a certain way.
>
> This problem is far more common with three-prong plugs after someone
> breaks off the ground lug. I got shocked in an arcade between two pinball
> machines, and when I checked one of the games it had the plug reversed.
> After I aligned the missing ground pin position the way it would have been
> plugged in if the ground were still present, there was no longer a shock
> when touching both metal panels. Of course, without a meter, I was very
> reluctant to test my theory because I really didn't want to get shocked
> again!
>
> Brian
>
>
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at synth-diy.org
> http://synth-diy.org/mailman/listinfo/synth-diy
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20170720/fdcb2fba/attachment.htm>


More information about the Synth-diy mailing list