<div dir="ltr"><div>I looked at Didier's pic and yes the center pin specifically says "earth ground". I'll admit that I got out in the weeds here, however the ebay link I had sent earlier also says GND on the center pin and has the added benefit of already being a DIN plug.</div><div><br></div><div><a href="https://www.ebay.com/itm/303827582131?hash=item46bd88fcb3:g:9D0AAOSweuFf6gew">https://www.ebay.com/itm/303827582131?hash=item46bd88fcb3:g:9D0AAOSweuFf6gew</a></div><div><br></div><div>I fail to see how this is a worse option than cutting a barrel plug AC adapter and wiring it up yourself.<br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Jul 6, 2022 at 4:55 AM Roman Sowa <<a href="mailto:modular@go2.pl">modular@go2.pl</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Exactly, it must be "grounded" in a sense of "earthed", and not <br>
"center-tap".<br>
If you connect center-tap transformer there, it will not be grounded, it <br>
will be floating. And also it will be very hot, because ground pin on <br>
the socket is shorthed to one of AC pins.<br>
<br>
You need a link from earth protect prong in your AC outlet to one end of <br>
your supply.<br>
It all becomes so clear when you look at power input schematics on page 4<br>
<br>
Do what Gordon says<br>
<br>
Roman<br>
<br>
W dniu 2022-07-06 o 08:05, Peter Pearson via Synth-diy pisze:<br>
> <a href="https://manuals.fdiskc.com/flat/BigBriar%20Etherwave%20Service%20Manual.pdf" rel="noreferrer" target="_blank">https://manuals.fdiskc.com/flat/BigBriar%20Etherwave%20Service%20Manual.pdf</a> <br>
> <<a href="https://manuals.fdiskc.com/flat/BigBriar%20Etherwave%20Service%20Manual.pdf" rel="noreferrer" target="_blank">https://manuals.fdiskc.com/flat/BigBriar%20Etherwave%20Service%20Manual.pdf</a>><br>
> <br>
> Read page 8 of the service manual where it says - and I'm quoting here - <br>
> "*WHY IS THE POWER ADAPTER GROUNDED?*"<br>
> <br>
> On Tue, Jul 5, 2022 at 7:04 AM Gordonjcp <<a href="mailto:gordonjcp@gjcp.net" target="_blank">gordonjcp@gjcp.net</a> <br>
> <mailto:<a href="mailto:gordonjcp@gjcp.net" target="_blank">gordonjcp@gjcp.net</a>>> wrote:<br>
> <br>
> On Thu, Jun 30, 2022 at 02:41:07PM -0400, Peter Pearson via<br>
> Synth-diy wrote:<br>
> ><br>
> <a href="https://manuals.fdiskc.com/flat/BigBriar%20Etherwave%20Service%20Manual.pdf" rel="noreferrer" target="_blank">https://manuals.fdiskc.com/flat/BigBriar%20Etherwave%20Service%20Manual.pdf</a><br>
> <<a href="https://manuals.fdiskc.com/flat/BigBriar%20Etherwave%20Service%20Manual.pdf" rel="noreferrer" target="_blank">https://manuals.fdiskc.com/flat/BigBriar%20Etherwave%20Service%20Manual.pdf</a>><br>
> ><br>
> > The schematic is here. A DC supply won't work. The theremin<br>
> might be<br>
> > fussy about grounding though, so you'll definitely want a<br>
> center-tap on<br>
> > your power adapter. I wouldn't recommend trying to cheat a<br>
> barrel jack AC<br>
> > power adapter in there.<br>
> <br>
> If you look at the power input circuit, there are only two<br>
> connections. There's nowhere for a centre-tap to go.<br>
> <br>
> It's a simple transformer fed into a pair of half-wave rectifiers,<br>
> same as the various crappy modular PSUs that are kicking around.<br>
> <br>
> Everyone is making this waaaaaaaaaaaaaaaaaaaaaaaaaaaaaay more<br>
> complicated than it needs to be.<br>
> <br>
> A 15V transformer will be fine. It doesn't need a centre tap. <br>
> Anything over 200mA will be fine.<br>
> <br>
> -- <br>
> Gordonjcp<br>
> <br>
> _______________________________________________<br>
> Synth-diy mailing list<br>
> <a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a> <mailto:<a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a>><br>
> <a href="http://synth-diy.org/mailman/listinfo/synth-diy" rel="noreferrer" target="_blank">http://synth-diy.org/mailman/listinfo/synth-diy</a><br>
> <<a href="http://synth-diy.org/mailman/listinfo/synth-diy" rel="noreferrer" target="_blank">http://synth-diy.org/mailman/listinfo/synth-diy</a>><br>
> Selling or trading? Use <a href="mailto:marketplace@synth-diy.org" target="_blank">marketplace@synth-diy.org</a><br>
> <mailto:<a href="mailto:marketplace@synth-diy.org" target="_blank">marketplace@synth-diy.org</a>><br>
> <br>
> <br>
> _______________________________________________<br>
> Synth-diy mailing list<br>
> <a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><br>
> <a href="http://synth-diy.org/mailman/listinfo/synth-diy" rel="noreferrer" target="_blank">http://synth-diy.org/mailman/listinfo/synth-diy</a><br>
> Selling or trading? Use <a href="mailto:marketplace@synth-diy.org" target="_blank">marketplace@synth-diy.org</a><br>
> <br>
</blockquote></div>