[sdiy] jörgens tri vco-bcv62

[Magnus Danielson]

From: cj3000 at gmx.de
Subject: [sdiy] jörgens tri vco-bcv62
Date: Mon, 27 Jan 2003 11:55:20 +0100 (MET)

> hello list,
> 
> i wanted to report that i succesfully build jörgens tri vco core with a
> bcv62 (rené schmitz told me the hint after asking about taking bc847bs´s for
> the
> smd 2040 vcf, where you also need pnp pairs) instead mat 03.  it seems to
> work pretty good, although i don´t know how temperatur will affect the
> output. 

Interesting...

> i just extended the pcbsolution jörgen made for the exp converter(bc847bs
> +tempco) and will put some "wärmeleitpaste" on it.

Ah, värmeledningspasta...

> know i wanted to know how i can change the frequency range, because with the
> values shown on jörgens site it does not go under 1Hz and i also want to use
> it as vclfo.

Toss in a larger cap in the core should do it. You want a non-polar low loss
cap (polypropylen for instance) to do the work. A cap 10 times as large reduces
frequency to the tenth for the same CV value.

Cheers,
Magnus