Hi Prophei.
Maybe check the 4K7 resistor that goes between "RE" on the schemo and
GND?.
Yesterday I just tested an orange REV1 board using a 5K trimmer there
to see what happened... :-)
It worked fine - with a trimmer value less than around 2.7K the
resonance really got intense, but with an increasing (unpleasant)
highpass filter effect, as the resistance was lowered.
cheers,
Dave
Maybe check the 4K7 resistor that goes between "RE" on the schemo and
GND?.
Yesterday I just tested an orange REV1 board using a 5K trimmer there
to see what happened... :-)
It worked fine - with a trimmer value less than around 2.7K the
resonance really got intense, but with an increasing (unpleasant)
highpass filter effect, as the resistance was lowered.
cheers,
Dave
On 11 Oct 2007, at 14:51, prophei wrote:
> hello all,
>
> i just put together my first cgs30 bandpass filter (rev2), and can't
> seem to notice any
> resonance at all. i can sweep it just fine, and there is maybe a
> "slight" ring in there
> somewhere... but the resonance pot does nothing.
>
> having built more complicated modules before, i immediately checked
> my soldering,
> followed the schematic...etc to look for obvious errors. i haven't
> found any yet. i have also
> tried 2 different pots for the resonance control, no change.
>
> the parts list on ken's page calls out 2x 100n caps as being used,
> yet i only see a few 10uf
> electrolitics and 22n's noted on my pcb board. there is no more room
> for caps on here, so
> what were those called out for??
>
> also, i am assuming that since i was not setting this up for using
> the "cx" cap, i just leave
> that empty... and i also assume that i am supposed to add a jumper
> where it appears to be
> indicated with 3 boxed symbols next to the beads/elec caps on the
> lower left side of the
> pcb.
>
> any help is greatly appreciated!
>
> -prophei
>
>
>
>
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