Converting trem lune to operate on jfet variable resistor?

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briggs
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Post by briggs »

Anyone got any ideas towards converting the Tremulus Lune to operate on a FET setup as a variable resistor rather than requiring the fairly expensive optocoupler?

This has been bugging me so much! I just can't figure this one out - I've tried all sorts of setups but the correct one is avoiding me like the plague!

Lune info is here: http://www.commonsound.com/kits/doku.ph ... d:tremulus
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Aharon
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Post by Aharon »

How about modding it to use an H11F1 or F3,the're jfet and $0.75 a piece or less.
Aharon

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trevize
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Post by trevize »

I hope you'll find these snippets useful!

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grolschie
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Post by grolschie »

Octocouplers are dead easy to make. I watched Bajaman whip one up in a few minutes. Perhaps PM him for technical details?

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briggs
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Post by briggs »

Yeah, I used to knock opto's up all the time. I just think it would be a nice mod for the circuit. I mean a fet is 10p but a LDR + LED is £1+

Thanks trevize. I'll give it another go tomorrow with some of those ideas!
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bajaman
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Post by bajaman »

Its only money - opto has much better linearity

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modman
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Post by modman »

Briggs,

Did you have luck using the JFET, or is it not worth it in view of performance?

ZJ
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