Yamaha DTXpress/DTXplorer/DTXtreme

--- In DTXpress@yahoogroups.com, "Keith" <keith@...> wrote:
>
> Jeff,
> 
> I have put a new circuit in the files section to make it clear where
> the capacitor goes.  If you use a polarised capacitor then the
> positive side should go to the collector.
> 
> Keith.
>

Ah I didn't see your post until just now.  I figured out where it 
needed to go, I was just going to post what I did.  Since the KP65 
already has a 1k resistor and a trimpot, the circuit is more 
responsive without R1 and VR1.  If you are building your own trigger 
you would want to have at least a 1k resistor and trim in the 
circuit.  I experimented with different caps and 1uf to 4uf seems to 
be a pretty good range.  No missed hits and the sensitivity is 
excellent.  I also found that the 2N3904 transistor felt a little 
better than the 2N4401 but both work well.  Light taps will now 
consistently be recognized by RB.  I have the trim all the way up on 
the KP65 without double hitting but still plenty sensitive.  I also 
created a Darlington pair circuit with caps and it felt about the 
same as the single transistor circuit with cap. 

Keith thank you very much for taking the time to draw up the circuits 
on what is pretty much an off topic subject.