[sdiy] Using BC847S in exponential converter

[Samppa Tolvanen]

On Sat, Aug 22, 2009 at 12:17 AM, Gerard<translucent at xs4all.nl> wrote:
> Hi,
>
> Well this is the one I ordered:
> http://www.produktinfo.conrad.com/datenblaetter/150000-174999/153224-da-01-en-AF_Transistor_BC847S.pdf
> which is a double transistor, but as mentioned by Samppa it is not a
> monolithic design (apparently), but at least the datasheet mentions that the
> transistor have "high matching", and I assume that the thermal coupling will
> also be high (given the incredible small size of the package), at least
> better than glueing two devices together.
>

Well, I think You know the deal already. Mr. Bergfors measured the
characteristics as in http://hem.bredband.net/bersyn/VCO/vco_quad.htm
and as I didn't have any control on the setup - Certainly a good value
for the money while hand picked. Much better, than in Dial-a-Tempco.