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Subject: [ModularSynthPanels] Re: tau pipe red/green led wiring?

From: Mark <yahoogroups@...>
Date: 2008-05-14

On 5/14/08, getloosegetloose put forth:
>I'm new to this forum. My first post. I hope it's ok to but into this
>topic. :)

I don't think we have a topic :)

>Here's my question though--even though a 2-lead dual LED won't work
>apparently--why wouldn't a 3-lead Dual work (with one lead common to
>both LED headers? Or is this not the way that 3-lead LEDs work?

All the three-wire LED's I've seen are common cathode. They are
connected in series, anode-cathode-cathode-anode, and the three leads
go anode-cathodes-anode. In the stock JH 20-pole phaser circuit, the
two separate LED's are in series, but go cathode-anode-cathode-anode.
So unless someone can find one wired that way, a three-wire LED won't
work.

Btw, a two-wire two-color LED has two LED's in parallel going in
opposite directions.

So since your phaser is built, could you please measure the output of
the LFO?? It goes to one side of the "Osc Level" pot, or the common
point for connecting the stock LED's. That's what we need to know in
order to design a driver for a two-color LED. And while you are at
it, could you also measure the output of the manual circuit??


Thanks :)