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Cgs synth

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Re: vca bc548 question

2012-12-23 by adematteo

Thanks Ken, I just wired up the vca and it sounds good to me.

I didn't match the bc548's so maybe i got lucky.

I did match the dual npn's using the HFE test function.

I don't have any trimmers yet so i'm hearing the thump of dc coming through but other than that the source signal sounded good.

Thanks for all your help !
-Tony

--- In cgs_synth@yahoogroups.com, sasami@... wrote:
>
> >That's good to know Ken !
> >Do you recommend using the HFE to match the transistors in your vco instead
> of the lm394 ?
> >I'm not concerned about 1v/o tracking being super accurate.
>
> If you aren't worried about accuracy, sure, that would do the trick.
> Separate transistors will never be as good as a dual, due to the thermal lag
> caused by the separation of the transistor dies in their own little epoxy
> packages.
>
> >Also, how do you "join" the 2 transistors together ?
>
> A wire tie around them, with them flat to flat will do the trick. Some
> people go as far as epoxying them together.
>
>
> Ken
> _______________________________________________________________________
> Ken Stone sasami@... otherunicorn@...
> Modular Synth PCBs for sale <http://www.cgs.synth.net/>
> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>

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