Mine isn`t working properly either, but based on what you said I`m
99.9999% sure your isn`t either. The VCO is supposed to clock the
filter, so the frequency of the filter changes with it. When the
filter receives no clock from the VCO, it seems to lock to a fixed
frequency which is below the audible range. Mine did this before I
fixed the VCO. The reason you get a filter sweep in the last 20% of
the bandwidth knob is because you are simply increasing the band large
enough to let some audio through, while the center point still sits in
the sub audio range, so it`s acting like a normal lowpass filter. At
least that`s how I interpreted it when my VCO wasn`t working.
Now, the VCO leaking through into the audio without clocking the
filter, that`s a new one to me. I`m no expert at this, so all I can
say is that it`s clear your filter and VCO are working, so your
problem mostly likely lies in the circuitry that is supposed to make
them work together. The filter is clocked by 3 outputs of the 4024, so
I`d check around there. Good luck.
99.9999% sure your isn`t either. The VCO is supposed to clock the
filter, so the frequency of the filter changes with it. When the
filter receives no clock from the VCO, it seems to lock to a fixed
frequency which is below the audible range. Mine did this before I
fixed the VCO. The reason you get a filter sweep in the last 20% of
the bandwidth knob is because you are simply increasing the band large
enough to let some audio through, while the center point still sits in
the sub audio range, so it`s acting like a normal lowpass filter. At
least that`s how I interpreted it when my VCO wasn`t working.
Now, the VCO leaking through into the audio without clocking the
filter, that`s a new one to me. I`m no expert at this, so all I can
say is that it`s clear your filter and VCO are working, so your
problem mostly likely lies in the circuitry that is supposed to make
them work together. The filter is clocked by 3 outputs of the 4024, so
I`d check around there. Good luck.
--- In cgs_synth@yahoogroups.com, casperelectronics <pete@...> wrote:
>
> Hello everyone.
> Sorry to continue the Bi-N-Tic questions. I know there have been a
> lot and I've read them all and I still have a few more.
> I think I got the whole thing working right but I'm not sure, it's a
> weird module (as I'm sure you'll all agree)
> The way it is working now it is really two modules, a filter and a
> VCO, but I don't see (or hear) much connection between the two.
>
> If I turn the coarse and fine tune knobs all the way down, there is
> no oscillator.
> Then if I feed a signal in the IN jack i can get some really nice
> filter cut sweeps using the BANDWIDTH knob and resonance using the
> DAMPER knob. The whole filter sweep is in the last 20% of turn of
> the bandwidth knob.
> As I turn UP the coarse tune, a square osc, mixes into the signal.
> It doesn't effect the filter, it just mixes into the audio path.
> When I turn it up almost beyond the audio range, the osc suddenly
> cuts off.
> Anyway.. maybe this is just how it works? I'd like to talk to
> someone who has built one or two of these so that I know if I should
> work on it some more.
> I really wish there was some kind of CV for filter cut. Am I missing
> something?
> Thanks!!!!
> -pete
>
>
>
>
>
> On Nov 28, 2008, at 9:54 PM, casperelectronics wrote:
>
> > Hey Scott,
> > I want to add the wave outputs on my bintic filter but I can't find
> > the info.
> > Do you sell daughter boards/ host schematics for that on your site??
> > Thanks!
> > -pete
> >
> >
>
>
>
> [Non-text portions of this message have been removed]
>