My new VCO

[Zsolt Homlokos]

Martin Czech schrieb:

> Nice circuit! (I have a problem with the .pdf, in the top left corner
> all semiconductor type names are at the same point...)
>
> > With the VCO running at rather high frequencies, a (possible)
> > leakage of the thyristor (is there any ? Martin ?) would not be
> > harmful either.
>
> Me ?
> Depends on the transistors, of course. I you have bad luck with a bad
> leaky Q1 or Q2there may be a problem. Select? I think the diode in the
> thyristor loop is there to controll the pull up point where the devices
> shuts off, but also is some kind of voltage devider together with Q3.
> For little currents the diode has a quite high resistance, but Q3 has
> also some beta, this may suppress leakeage currents, preventing them from
> beeing transformed into a Q1 base voltage. OTOH the Q3 is also there to
> compensate temperature driven Ube loss of Q1, the trigger point should
> be fairly stable...
>
> m.c.

  is this chinese or what?   :)
i feel bad .....this is currentely too demanding for my limited knowledge
but was fun to read.