tb303 vco

[Fraser, Colin J]

> -----Original Message-----
> From: Heiko van der Linden [mailto:H.J.vanderlinden at stud.far.ruu.nl]
> Sent: 18 November 1998 09:00
> To: synth-diy at mailhost.bpa.nl
> Subject: tb303 vco
> 
> I have recently modded my tb303 vco by replacing the q27 with a bd438
> (medium power trannie) and guess what !
> No more start up problems and no more burn outs. (I can even short all
> the terminals with my finger and no burnout occurs)
> A small signal transistor like the bc547 isn't capable of 
> taking care of
> the large currents that flow in the scr circuit.
> The wave form is identical to the original and it sounds the same too.
> I hope to have helped someone.

I used a BC218L for q27 in my clone and never had any problem.

Colin f