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synthacon level and resonance control questions

synthacon level and resonance control questions

2004-12-02 by hiriseau

hey guys, well i finally got most of my parts together, enough to get
it working anyway.

i built it per the schematic revision and guide, im using an opa227
(because i had it lieing around from another project) and i added 2.2k
in paralell with the 1k per john's advice.

i do have some problems though. running the same input to all bp hp lp
(just for the moment until i get my switches to switch each band on
and off).

the resonance pot is EXTREMELY crackly whenever i move it. i checked
the solders and they seemed to be ok. i am about to try resolder it
all but i tried it before and it made no difference. here is an mp3
sample of what happens when i adjust the resonance pot
http://users.bigpond.net.au/xpander/resonance.mp3 im thinking the pot
i have (alpha 9mm linear 1k) is a dud. are there any other points on
the board that would be worth me looking at? the two transistors
before the pot, could they be causing the problem? i will try hooking
the pot up the other way round, but the noise to me doesnt indicate
incorrect hooke up. im not well versed on pots in synths/filters.

secondly, levels. i have the link in and i have a 50k log pot in (the
same 9mm alpha) and it doesnt seem to be working too well. it is low
in volume then BANG heaps of volume. my suspicion is that i should be
using a linear pot instead of a log pot. this is what it sounds like
http://users.bigpond.net.au/xpander/level.mp3 would i be better off
using the pot as an attenuator on the input stage, and using a trim
pot on the level to tweak it to where i want?

apart from those two problems, ive got a bit of humm in the system
that i will troubleshoot out later (suspect its from the audio input
matrix), can't see it being too hard ;)

when i set the level and leave the resonance, the frequency sweeping
sounds lovely, i can't wait to get this working nicely :)

hope you guys can help me out here :)

thanks

sean

Re: synthacon level and resonance control questions

2004-12-02 by sasami@hotkey.net.au

>the resonance pot is EXTREMELY crackly whenever i move it.

That's a dud pot. It isn't a solder issue, but rather dust or "corrosion" on
the pot resistive strip. A shot of electrolube contact cleaner may help. A
better pot is the best solution.

>secondly, levels. i have the link in and i have a 50k log pot in (the
>same 9mm alpha) and it doesnt seem to be working too well. it is low
>in volume then BANG heaps of volume. my suspicion is that i should be
>using a linear pot instead of a log pot. this is what it sounds like
>http://users.bigpond.net.au/xpander/level.mp3 would i be better off
>using the pot as an attenuator on the input stage, and using a trim
>pot on the level to tweak it to where i want?

Yes, a linear pot would probably be better. In fact, I rarely use log pots
in synthesizers at all.

Ken

_______________________________________________________________________
Ken Stone sasami@... or sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

Re: synthacon level and resonance control questions

2004-12-02 by hiriseau

thanks i will get another one pronto, its a sealed pot so nothing i
can really do about it. and its only a couple of dollars to get a new
one.

with the level, considering that i will be using the filter in a tweak
hard on the fly sort of role, would i be better off using the trim pot
to set the output level and then attenuator on the input, so that i
don't kill any club sound systems and peoples ears?
Show quoted textHide quoted text
--- In cgs_synth@yahoogroups.com, sasami@h... wrote:
> >the resonance pot is EXTREMELY crackly whenever i move it.
>
> That's a dud pot. It isn't a solder issue, but rather dust or
"corrosion" on
> the pot resistive strip. A shot of electrolube contact cleaner may
help. A
> better pot is the best solution.
>
> >secondly, levels. i have the link in and i have a 50k log pot in (the
> >same 9mm alpha) and it doesnt seem to be working too well. it is low
> >in volume then BANG heaps of volume. my suspicion is that i should be
> >using a linear pot instead of a log pot. this is what it sounds like
> >http://users.bigpond.net.au/xpander/level.mp3 would i be better off
> >using the pot as an attenuator on the input stage, and using a trim
> >pot on the level to tweak it to where i want?
>
> Yes, a linear pot would probably be better. In fact, I rarely use
log pots
> in synthesizers at all.
>
> Ken
>
> _______________________________________________________________________
> Ken Stone sasami@h... or sasami@c...
> Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

Re: synthacon level and resonance control questions

2004-12-02 by peng3002

Hold up before replacing the pot. I had a similar problem ith the Res
pot. It actually came from other pots/jacks not being grounded. Next
to the power supply header there is a "6V" hole on the pcb. Make sure
if your using this hole to run a ground line to pots/jacks to solder
a link to the ground trace right next to it. Cleared up my crackle
problems, maybe it'll work for you.

As far as output levels go...I took out the link and replaced it with
a 390K resistor.

As a side note: I think Ken says to breadboard first. This is great
advice. For instance: I built the pulse divider and it works
perfectly, but it puts out 13-15volts and I would have preferred
5volts. It's simply a matter of changing some resistors to get the
output level I want, but after everything is wired solder work can be
a little awkward.

Phil
Show quoted textHide quoted text
--- In cgs_synth@yahoogroups.com, "hiriseau" <sean@p...> wrote:
>
> thanks i will get another one pronto, its a sealed pot so nothing i
> can really do about it. and its only a couple of dollars to get a
new
> one.
>
> with the level, considering that i will be using the filter in a
tweak
> hard on the fly sort of role, would i be better off using the trim
pot
> to set the output level and then attenuator on the input, so that i
> don't kill any club sound systems and peoples ears?
>
> --- In cgs_synth@yahoogroups.com, sasami@h... wrote:
> > >the resonance pot is EXTREMELY crackly whenever i move it.
> >
> > That's a dud pot. It isn't a solder issue, but rather dust or
> "corrosion" on
> > the pot resistive strip. A shot of electrolube contact cleaner may
> help. A
> > better pot is the best solution.
> >
> > >secondly, levels. i have the link in and i have a 50k log pot in
(the
> > >same 9mm alpha) and it doesnt seem to be working too well. it is
low
> > >in volume then BANG heaps of volume. my suspicion is that i
should be
> > >using a linear pot instead of a log pot. this is what it sounds
like
> > >http://users.bigpond.net.au/xpander/level.mp3 would i be better
off
> > >using the pot as an attenuator on the input stage, and using a
trim
> > >pot on the level to tweak it to where i want?
> >
> > Yes, a linear pot would probably be better. In fact, I rarely use
> log pots
> > in synthesizers at all.
> >
> > Ken
> >
> >
______________________________________________________________________
_
> > Ken Stone sasami@h... or sasami@c...
> > Modular Synth PCBs for sale
<http://www.blaze.net.au/~sasami/synth/>
> > Australian Miniature Horses & Ponies
<http://www.blaze.net.au/~sasami/>

Re: synthacon level and resonance control questions

2004-12-03 by hiriseau

even when grounding the pot like that it had no effect. ive picked up
a replacement and will try it out. what ive done is run the ground
wire to some stripboard (thats old and oxidised, hence i think its the
source of the humm, not taking solder joints well)then all ground
connections in and out of that.

i'll let you guys know how i go replacing the pot. also picked up a
linear pot for the level control. wont be able to get in front of the
iron until tomorrow ;)
Show quoted textHide quoted text
--- In cgs_synth@yahoogroups.com, "peng3002" <peng3002@y...> wrote:
>
> Hold up before replacing the pot. I had a similar problem ith the Res
> pot. It actually came from other pots/jacks not being grounded. Next
> to the power supply header there is a "6V" hole on the pcb. Make sure
> if your using this hole to run a ground line to pots/jacks to solder
> a link to the ground trace right next to it. Cleared up my crackle
> problems, maybe it'll work for you.
>
> As far as output levels go...I took out the link and replaced it with
> a 390K resistor.
>
> As a side note: I think Ken says to breadboard first. This is great
> advice. For instance: I built the pulse divider and it works
> perfectly, but it puts out 13-15volts and I would have preferred
> 5volts. It's simply a matter of changing some resistors to get the
> output level I want, but after everything is wired solder work can be
> a little awkward.
>
> Phil
>
>
> --- In cgs_synth@yahoogroups.com, "hiriseau" <sean@p...> wrote:
> >
> > thanks i will get another one pronto, its a sealed pot so nothing i
> > can really do about it. and its only a couple of dollars to get a
> new
> > one.
> >
> > with the level, considering that i will be using the filter in a
> tweak
> > hard on the fly sort of role, would i be better off using the trim
> pot
> > to set the output level and then attenuator on the input, so that i
> > don't kill any club sound systems and peoples ears?
> >
> > --- In cgs_synth@yahoogroups.com, sasami@h... wrote:
> > > >the resonance pot is EXTREMELY crackly whenever i move it.
> > >
> > > That's a dud pot. It isn't a solder issue, but rather dust or
> > "corrosion" on
> > > the pot resistive strip. A shot of electrolube contact cleaner may
> > help. A
> > > better pot is the best solution.
> > >
> > > >secondly, levels. i have the link in and i have a 50k log pot in
> (the
> > > >same 9mm alpha) and it doesnt seem to be working too well. it is
> low
> > > >in volume then BANG heaps of volume. my suspicion is that i
> should be
> > > >using a linear pot instead of a log pot. this is what it sounds
> like
> > > >http://users.bigpond.net.au/xpander/level.mp3 would i be better
> off
> > > >using the pot as an attenuator on the input stage, and using a
> trim
> > > >pot on the level to tweak it to where i want?
> > >
> > > Yes, a linear pot would probably be better. In fact, I rarely use
> > log pots
> > > in synthesizers at all.
> > >
> > > Ken
> > >
> > >
> ______________________________________________________________________
> _
> > > Ken Stone sasami@h... or sasami@c...
> > > Modular Synth PCBs for sale
> <http://www.blaze.net.au/~sasami/synth/>
> > > Australian Miniature Horses & Ponies
> <http://www.blaze.net.au/~sasami/>

scratchy res pot on synthacon is still around

2004-12-06 by hiriseau

ok so i went out and bought a new pot just to drop in in case the pot
i had was bad. seemed it was. i dropped it in and still its scratchy.
is it possible that i am wiring the legs of the pot up wrong? whilst
trawling the message archives i noted that ken advises that the third
leg of the pot is not connected hence i havent grounded it.

i was about to try peng's suggestions but then i realised i have
nothing connected to the +6v pad.

i run the ground to the frequency pot then run the ground across to
some perfboard where ive tied in the grounds of the input output and
volume pot. the 6v connector isnt used at all!
Show quoted textHide quoted text
--- In cgs_synth@yahoogroups.com, "peng3002" <peng3002@y...> wrote:
>
> Hold up before replacing the pot. I had a similar problem ith the Res
> pot. It actually came from other pots/jacks not being grounded. Next
> to the power supply header there is a "6V" hole on the pcb. Make sure
> if your using this hole to run a ground line to pots/jacks to solder
> a link to the ground trace right next to it. Cleared up my crackle
> problems, maybe it'll work for you.
>
> As far as output levels go...I took out the link and replaced it with
> a 390K resistor.
>
> As a side note: I think Ken says to breadboard first. This is great
> advice. For instance: I built the pulse divider and it works
> perfectly, but it puts out 13-15volts and I would have preferred
> 5volts. It's simply a matter of changing some resistors to get the
> output level I want, but after everything is wired solder work can be
> a little awkward.
>
> Phil
>
>
> --- In cgs_synth@yahoogroups.com, "hiriseau" <sean@p...> wrote:
> >
> > thanks i will get another one pronto, its a sealed pot so nothing i
> > can really do about it. and its only a couple of dollars to get a
> new
> > one.
> >
> > with the level, considering that i will be using the filter in a
> tweak
> > hard on the fly sort of role, would i be better off using the trim
> pot
> > to set the output level and then attenuator on the input, so that i
> > don't kill any club sound systems and peoples ears?
> >
> > --- In cgs_synth@yahoogroups.com, sasami@h... wrote:
> > > >the resonance pot is EXTREMELY crackly whenever i move it.
> > >
> > > That's a dud pot. It isn't a solder issue, but rather dust or
> > "corrosion" on
> > > the pot resistive strip. A shot of electrolube contact cleaner may
> > help. A
> > > better pot is the best solution.
> > >
> > > >secondly, levels. i have the link in and i have a 50k log pot in
> (the
> > > >same 9mm alpha) and it doesnt seem to be working too well. it is
> low
> > > >in volume then BANG heaps of volume. my suspicion is that i
> should be
> > > >using a linear pot instead of a log pot. this is what it sounds
> like
> > > >http://users.bigpond.net.au/xpander/level.mp3 would i be better
> off
> > > >using the pot as an attenuator on the input stage, and using a
> trim
> > > >pot on the level to tweak it to where i want?
> > >
> > > Yes, a linear pot would probably be better. In fact, I rarely use
> > log pots
> > > in synthesizers at all.
> > >
> > > Ken
> > >
> > >
> ______________________________________________________________________
> _
> > > Ken Stone sasami@h... or sasami@c...
> > > Modular Synth PCBs for sale
> <http://www.blaze.net.au/~sasami/synth/>
> > > Australian Miniature Horses & Ponies
> <http://www.blaze.net.au/~sasami/>

Re: scratchy res pot on synthacon is still around

2004-12-06 by sasami@hotkey.net.au

The +6V is only there as part of a bus system I was using in some of my
panels that did require +6V - old Serge stuff mostly. 6 volts is not used in
any CGS board.

One known cause of scratchiness showing with pots is if there is a DC signal
involved. I don't know if the following will help or be a total failure, but
try placing a 10uF electro in series with the pot to block any DC component.
Before you do though, us a multimeter to work out which end is more positive
so you get the cap in the right way around.

Ken
Show quoted textHide quoted text
>
>
>ok so i went out and bought a new pot just to drop in in case the pot
>i had was bad. seemed it was. i dropped it in and still its scratchy.
>is it possible that i am wiring the legs of the pot up wrong? whilst
>trawling the message archives i noted that ken advises that the third
>leg of the pot is not connected hence i havent grounded it.
>
>i was about to try peng's suggestions but then i realised i have
>nothing connected to the +6v pad.
>
>i run the ground to the frequency pot then run the ground across to
>some perfboard where ive tied in the grounds of the input output and
>volume pot. the 6v connector isnt used at all!
>
>--- In cgs_synth@yahoogroups.com, "peng3002" <peng3002@y...> wrote:
>>
>> Hold up before replacing the pot. I had a similar problem ith the Res
>> pot. It actually came from other pots/jacks not being grounded. Next
>> to the power supply header there is a "6V" hole on the pcb. Make sure
>> if your using this hole to run a ground line to pots/jacks to solder
>> a link to the ground trace right next to it. Cleared up my crackle
>> problems, maybe it'll work for you.
>>
>> As far as output levels go...I took out the link and replaced it with
>> a 390K resistor.
>>
>> As a side note: I think Ken says to breadboard first. This is great
>> advice. For instance: I built the pulse divider and it works
>> perfectly, but it puts out 13-15volts and I would have preferred
>> 5volts. It's simply a matter of changing some resistors to get the
>> output level I want, but after everything is wired solder work can be
>> a little awkward.
>>
>> Phil
>>
>>
>> --- In cgs_synth@yahoogroups.com, "hiriseau" <sean@p...> wrote:
>> >
>> > thanks i will get another one pronto, its a sealed pot so nothing i
>> > can really do about it. and its only a couple of dollars to get a
>> new
>> > one.
>> >
>> > with the level, considering that i will be using the filter in a
>> tweak
>> > hard on the fly sort of role, would i be better off using the trim
>> pot
>> > to set the output level and then attenuator on the input, so that i
>> > don't kill any club sound systems and peoples ears?
>> >
>> > --- In cgs_synth@yahoogroups.com, sasami@h... wrote:
>> > > >the resonance pot is EXTREMELY crackly whenever i move it.
>> > >
>> > > That's a dud pot. It isn't a solder issue, but rather dust or
>> > "corrosion" on
>> > > the pot resistive strip. A shot of electrolube contact cleaner may
>> > help. A
>> > > better pot is the best solution.
>> > >
>> > > >secondly, levels. i have the link in and i have a 50k log pot in
>> (the
>> > > >same 9mm alpha) and it doesnt seem to be working too well. it is
>> low
>> > > >in volume then BANG heaps of volume. my suspicion is that i
>> should be
>> > > >using a linear pot instead of a log pot. this is what it sounds
>> like
>> > > >http://users.bigpond.net.au/xpander/level.mp3 would i be better
>> off
>> > > >using the pot as an attenuator on the input stage, and using a
>> trim
>> > > >pot on the level to tweak it to where i want?
>> > >
>> > > Yes, a linear pot would probably be better. In fact, I rarely use
>> > log pots
>> > > in synthesizers at all.
>> > >
>> > > Ken
>> > >
>> > >
>> ______________________________________________________________________
>> _
>> > > Ken Stone sasami@h... or sasami@c...
>> > > Modular Synth PCBs for sale
>> <http://www.blaze.net.au/~sasami/synth/>
>> > > Australian Miniature Horses & Ponies
>> <http://www.blaze.net.au/~sasami/>
>
>
>
>
>
>
>See the following URLS for the CGS Modular Synth home page:
>Main: http://www.cgs.synth.net/
>Secondary: http://otherunicorn.0catch.com/synth/
>Yahoo! Groups Links
>
>
>
>
>
>
>
>
_______________________________________________________________________
Ken Stone sasami@... or sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

Re: scratchy res pot on synthacon is still around

2004-12-08 by hiriseau

thanks. when i get a chance i will look in to this.

is it possible that the dc leak is coming from the power supply? im
using the cgs14 built to spec with positive measuring 14.8-14.95 and
negative sitting happily on 15v. i am thinking one of my filter caps
or possibly the positive regulator isnt working right. i am thinking
that a low battery in my multimeter could also be contributing to this
reading on the positive voltage.

if its not the psu where would u trace back the dc to? i will try
installing that cap but i would rather keep it clean and to the boards
spec.
Show quoted textHide quoted text
--- In cgs_synth@yahoogroups.com, sasami@h... wrote:
> The +6V is only there as part of a bus system I was using in some of my
> panels that did require +6V - old Serge stuff mostly. 6 volts is not
used in
> any CGS board.
>
> One known cause of scratchiness showing with pots is if there is a
DC signal
> involved. I don't know if the following will help or be a total
failure, but
> try placing a 10uF electro in series with the pot to block any DC
component.
> Before you do though, us a multimeter to work out which end is more
positive
> so you get the cap in the right way around.
>
> Ken
>
>
> >
> >
> >ok so i went out and bought a new pot just to drop in in case the pot
> >i had was bad. seemed it was. i dropped it in and still its scratchy.
> >is it possible that i am wiring the legs of the pot up wrong? whilst
> >trawling the message archives i noted that ken advises that the third
> >leg of the pot is not connected hence i havent grounded it.
> >
> >i was about to try peng's suggestions but then i realised i have
> >nothing connected to the +6v pad.
> >
> >i run the ground to the frequency pot then run the ground across to
> >some perfboard where ive tied in the grounds of the input output and
> >volume pot. the 6v connector isnt used at all!
> >
> >--- In cgs_synth@yahoogroups.com, "peng3002" <peng3002@y...> wrote:
> >>
> >> Hold up before replacing the pot. I had a similar problem ith the
Res
> >> pot. It actually came from other pots/jacks not being grounded. Next
> >> to the power supply header there is a "6V" hole on the pcb. Make
sure
> >> if your using this hole to run a ground line to pots/jacks to solder
> >> a link to the ground trace right next to it. Cleared up my crackle
> >> problems, maybe it'll work for you.
> >>
> >> As far as output levels go...I took out the link and replaced it
with
> >> a 390K resistor.
> >>
> >> As a side note: I think Ken says to breadboard first. This is great
> >> advice. For instance: I built the pulse divider and it works
> >> perfectly, but it puts out 13-15volts and I would have preferred
> >> 5volts. It's simply a matter of changing some resistors to get the
> >> output level I want, but after everything is wired solder work
can be
> >> a little awkward.
> >>
> >> Phil
> >>
> >>
> >> --- In cgs_synth@yahoogroups.com, "hiriseau" <sean@p...> wrote:
> >> >
> >> > thanks i will get another one pronto, its a sealed pot so nothing i
> >> > can really do about it. and its only a couple of dollars to get a
> >> new
> >> > one.
> >> >
> >> > with the level, considering that i will be using the filter in a
> >> tweak
> >> > hard on the fly sort of role, would i be better off using the trim
> >> pot
> >> > to set the output level and then attenuator on the input, so that i
> >> > don't kill any club sound systems and peoples ears?
> >> >
> >> > --- In cgs_synth@yahoogroups.com, sasami@h... wrote:
> >> > > >the resonance pot is EXTREMELY crackly whenever i move it.
> >> > >
> >> > > That's a dud pot. It isn't a solder issue, but rather dust or
> >> > "corrosion" on
> >> > > the pot resistive strip. A shot of electrolube contact
cleaner may
> >> > help. A
> >> > > better pot is the best solution.
> >> > >
> >> > > >secondly, levels. i have the link in and i have a 50k log
pot in
> >> (the
> >> > > >same 9mm alpha) and it doesnt seem to be working too well.
it is
> >> low
> >> > > >in volume then BANG heaps of volume. my suspicion is that i
> >> should be
> >> > > >using a linear pot instead of a log pot. this is what it sounds
> >> like
> >> > > >http://users.bigpond.net.au/xpander/level.mp3 would i be better
> >> off
> >> > > >using the pot as an attenuator on the input stage, and using a
> >> trim
> >> > > >pot on the level to tweak it to where i want?
> >> > >
> >> > > Yes, a linear pot would probably be better. In fact, I rarely use
> >> > log pots
> >> > > in synthesizers at all.
> >> > >
> >> > > Ken
> >> > >
> >> > >
> >>
______________________________________________________________________
> >> _
> >> > > Ken Stone sasami@h... or sasami@c...
> >> > > Modular Synth PCBs for sale
> >> <http://www.blaze.net.au/~sasami/synth/>
> >> > > Australian Miniature Horses & Ponies
> >> <http://www.blaze.net.au/~sasami/>
> >
> >
> >
> >
> >
> >
> >See the following URLS for the CGS Modular Synth home page:
> >Main: http://www.cgs.synth.net/
> >Secondary: http://otherunicorn.0catch.com/synth/
> >Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
> >
> _______________________________________________________________________
> Ken Stone sasami@h... or sasami@c...
> Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

Re: scratchy res pot on synthacon is still around

2004-12-08 by sasami@hotkey.net.au

Any DC present in the circuit at that point would be inherent in the design.
It's just not caused problems before. There isn't a "leak" as such to be
tracked down. For the purposes of test, lift the wire from the pot itself,
and add the capacitor there. Don't modify the PCB.

Ken
Show quoted textHide quoted text
>
>
>thanks. when i get a chance i will look in to this.
>
>is it possible that the dc leak is coming from the power supply? im
>using the cgs14 built to spec with positive measuring 14.8-14.95 and
>negative sitting happily on 15v. i am thinking one of my filter caps
>or possibly the positive regulator isnt working right. i am thinking
>that a low battery in my multimeter could also be contributing to this
> reading on the positive voltage.
>
>if its not the psu where would u trace back the dc to? i will try
>installing that cap but i would rather keep it clean and to the boards
>spec.
>
>--- In cgs_synth@yahoogroups.com, sasami@h... wrote:
>> The +6V is only there as part of a bus system I was using in some of my
>> panels that did require +6V - old Serge stuff mostly. 6 volts is not
>used in
>> any CGS board.
>>
>> One known cause of scratchiness showing with pots is if there is a
>DC signal
>> involved. I don't know if the following will help or be a total
>failure, but
>> try placing a 10uF electro in series with the pot to block any DC
>component.
>> Before you do though, us a multimeter to work out which end is more
>positive
>> so you get the cap in the right way around.
>>
>> Ken
>>
>>
>> >
>> >
>> >ok so i went out and bought a new pot just to drop in in case the pot
>> >i had was bad. seemed it was. i dropped it in and still its scratchy.
>> >is it possible that i am wiring the legs of the pot up wrong? whilst
>> >trawling the message archives i noted that ken advises that the third
>> >leg of the pot is not connected hence i havent grounded it.
>> >
>> >i was about to try peng's suggestions but then i realised i have
>> >nothing connected to the +6v pad.
>> >
>> >i run the ground to the frequency pot then run the ground across to
>> >some perfboard where ive tied in the grounds of the input output and
>> >volume pot. the 6v connector isnt used at all!
>> >
>> >--- In cgs_synth@yahoogroups.com, "peng3002" <peng3002@y...> wrote:
>> >>
>> >> Hold up before replacing the pot. I had a similar problem ith the
>Res
>> >> pot. It actually came from other pots/jacks not being grounded. Next
>> >> to the power supply header there is a "6V" hole on the pcb. Make
>sure
>> >> if your using this hole to run a ground line to pots/jacks to solder
>> >> a link to the ground trace right next to it. Cleared up my crackle
>> >> problems, maybe it'll work for you.
>> >>
>> >> As far as output levels go...I took out the link and replaced it
>with
>> >> a 390K resistor.
>> >>
>> >> As a side note: I think Ken says to breadboard first. This is great
>> >> advice. For instance: I built the pulse divider and it works
>> >> perfectly, but it puts out 13-15volts and I would have preferred
>> >> 5volts. It's simply a matter of changing some resistors to get the
>> >> output level I want, but after everything is wired solder work
>can be
>> >> a little awkward.
>> >>
>> >> Phil
>> >>
>> >>
>> >> --- In cgs_synth@yahoogroups.com, "hiriseau" <sean@p...> wrote:
>> >> >
>> >> > thanks i will get another one pronto, its a sealed pot so nothing i
>> >> > can really do about it. and its only a couple of dollars to get a
>> >> new
>> >> > one.
>> >> >
>> >> > with the level, considering that i will be using the filter in a
>> >> tweak
>> >> > hard on the fly sort of role, would i be better off using the trim
>> >> pot
>> >> > to set the output level and then attenuator on the input, so that i
>> >> > don't kill any club sound systems and peoples ears?
>> >> >
>> >> > --- In cgs_synth@yahoogroups.com, sasami@h... wrote:
>> >> > > >the resonance pot is EXTREMELY crackly whenever i move it.
>> >> > >
>> >> > > That's a dud pot. It isn't a solder issue, but rather dust or
>> >> > "corrosion" on
>> >> > > the pot resistive strip. A shot of electrolube contact
>cleaner may
>> >> > help. A
>> >> > > better pot is the best solution.
>> >> > >
>> >> > > >secondly, levels. i have the link in and i have a 50k log
>pot in
>> >> (the
>> >> > > >same 9mm alpha) and it doesnt seem to be working too well.
>it is
>> >> low
>> >> > > >in volume then BANG heaps of volume. my suspicion is that i
>> >> should be
>> >> > > >using a linear pot instead of a log pot. this is what it sounds
>> >> like
>> >> > > >http://users.bigpond.net.au/xpander/level.mp3 would i be better
>> >> off
>> >> > > >using the pot as an attenuator on the input stage, and using a
>> >> trim
>> >> > > >pot on the level to tweak it to where i want?
>> >> > >
>> >> > > Yes, a linear pot would probably be better. In fact, I rarely use
>> >> > log pots
>> >> > > in synthesizers at all.
>> >> > >
>> >> > > Ken
>> >> > >
>> >> > >
>> >>
>______________________________________________________________________
>> >> _
>> >> > > Ken Stone sasami@h... or sasami@c...
>> >> > > Modular Synth PCBs for sale
>> >> <http://www.blaze.net.au/~sasami/synth/>
>> >> > > Australian Miniature Horses & Ponies
>> >> <http://www.blaze.net.au/~sasami/>
>> >
>> >
>> >
>> >
>> >
>> >
>> >See the following URLS for the CGS Modular Synth home page:
>> >Main: http://www.cgs.synth.net/
>> >Secondary: http://otherunicorn.0catch.com/synth/
>> >Yahoo! Groups Links
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> _______________________________________________________________________
>> Ken Stone sasami@h... or sasami@c...
>> Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
>> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>
>
>
>
>
>
>See the following URLS for the CGS Modular Synth home page:
>Main: http://www.cgs.synth.net/
>Secondary: http://otherunicorn.0catch.com/synth/
>Yahoo! Groups Links
>
>
>
>
>
>
>
>
_______________________________________________________________________
Ken Stone sasami@... or sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

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