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CGS48 - VCO -- some questions

CGS48 - VCO -- some questions

2006-03-07 by Jan Czmok

Hi all,

i just successfully build the CGS48 and some questions appeared:

- i hear the VCO only if i "touch" the TL072 on the lower left side, so
i assume the ground is somwhere missed or wrongly connected.

a) i know about the 0V/GND, GND and VG, which one to use for the
ground connection of the Input/output Jacks ?
b) Tune pot/Fine Tune pot, both values 100K or 1M/100K ??
c) When using +/- 15V, which resistors need to be changed on the
recent version ?

Thanks for any help !

--jan

Re: CGS48 - VCO -- some questions

2006-03-07 by bbluthang

hi
>
> - i hear the VCO only if i "touch" the TL072 on the lower left
side, so
> i assume the ground is somwhere missed or wrongly connected.

i had this problem once on a VCO and found i hadn't soldered one pin
on the chip - check your soldering?
>
> a) i know about the 0V/GND, GND and VG, which one to use
for the
> ground connection of the Input/output Jacks ?
use 0V or GND. The VG input is for connecting up extra inputs or
pots for those who want more.

> b) Tune pot/Fine Tune pot, both values 100K or 1M/100K ??

use 100K for tune and 1M for fine tune.


> c) When using +/- 15V, which resistors need to be changed
on the
> recent version ?
nothing, just stuff as marked.
(if you are using +/-12V you need to on the input to the 311).
hope this helps
andrew

Re: CGS48 - VCO -- some questions

2006-03-07 by bbluthang

> > b) Tune pot/Fine Tune pot, both values 100K or 1M/100K ??
>
> use 100K for tune and 1M for fine tune.
>
i should be more specific, if you use 100K/1M and the accompanying
diode, you can enjoy a greater range on your tune pot - as Ken wrote -
crank it down to LFO speeds.

no diode,no 1M, just the 100K would give very coarse tuning.
@

Re: CGS48 - VCO -- some questions

2006-03-07 by Richard Brewster

Although I built mine a little differently, you might want to have a look:

http://www.pugix.com/cgs-vco.htm

-Richard Brewster

Jan Czmok wrote:
Show quoted textHide quoted text
>Hi all,
>
>i just successfully build the CGS48 and some questions appeared:
>
>- i hear the VCO only if i "touch" the TL072 on the lower left side, so
>i assume the ground is somwhere missed or wrongly connected.
>
> a) i know about the 0V/GND, GND and VG, which one to use for the
>ground connection of the Input/output Jacks ?
> b) Tune pot/Fine Tune pot, both values 100K or 1M/100K ??
> c) When using +/- 15V, which resistors need to be changed on the
>recent version ?
>
>Thanks for any help !
>
>--jan
>
>
>
>
>The CGS Modular Synth home page: http://www.cgs.synth.net/
>
>Yahoo! Groups Links
>
>
>
>
>
>
>
>
>
>

Re: CGS48 - VCO -- some questions

2006-03-09 by Jan-Ahrent Czmok

Hi all,

i got a bit further; it seems that the Problem with the "touching IC"
can be isolated to the pin 2/3/4 and the pro SP trimpot.
once i touched (!) the Pin 2/3/4 the VCO oscillates.

i successfully got audio of SAW+/SAW and SINE, however haven't looked
at the power neither oscillator view.

1)

I tried to run the VCO with a bit of CV1 in from an LFO, but this
does not seem to work either with or
without Pot.

2)

How do i need to connect the POT ? Middle Pin goes to CV (right
beside the PLS connector), left pin to jacket and right pin to Ground ?
Info: Pot is 100Klin, so as all pots are.

3)

COARSE/FINE. have a TUNE input and 2 pots (both 100klin). How do
those get connected ?
cause i got a "Tune" connector on the PCB and 2 pots.


Thanks again for any help ... Progress seems slow, but steady.

p.s.: of that what i heard from the VCO is superb (SAW/SINE) :-)


--jan

Re: CGS48 - VCO -- some questions

2006-03-09 by c10h14no2i

I can answer two of your questions...

>
> 2)
>
> How do i need to connect the POT ? Middle Pin goes to CV (right
> beside the PLS connector), left pin to jacket and right pin to Ground ?
> Info: Pot is 100Klin, so as all pots are.

the CV1 and CV2 inputs on the pcb are for the processor section.
Those jacks connect directly to the PCB w/out going through a pot.

The processor pots both connect to "pcw" and "pccw" The middle of
processor pot 1 connects to "pw1", and middle pin of processor pot two
to "pw2"

If you were wiring up a pot for FM or something, then you would wire
the right to ground, left to the jack and middle to the PCB

>
> 3)
>
> COARSE/FINE. have a TUNE input and 2 pots (both 100klin). How do
> those get connected ?
> cause i got a "Tune" connector on the PCB and 2 pots.

For both tune pots you connect the left ends to the positive and right
ends to negative supplies (when looking at the back of the pot w/ pins
down). The middle of the main tune pot goes to "tune" on the pcb.
The middle of the fine tune pot goes to "cvsn" on the PCB, but you
have to put it through a high value resistor. 4 to 10m.

You should try reading through the CGS VCO page. That info is listed
there. The VCO was one of the first modules I built, and I had to
read that page about 10 times before I got it.... but it finally sunk
in.
http://www.cgs.synth.net/modules/cgs48_vco.html


> p.s.: of that what i heard from the VCO is superb (SAW/SINE) :-)
>
Its definitely worth the effort! All of the CGS modules are great.

-Scott

For sale/trade: CGS Bi-N-Tic PCB

2006-03-09 by Adam Schabtach

Greetings,

I have a Bi-N-Tic PC board that needs a new home. Due to changing whims and
interests I doubt that I'm going to use it. It is in like-new condition, as
received from Ken. I'll throw in the paper copy of the Bi-N-Tic web page I
ran off on my printer.

I'll mail it within the United States for $10. PayPal would be dandy but
other forms of exchange are probably okay, too. I'd really rather not ship
it overseas because I don't like standing in line at the post office.

Alternatively, I'll entertain offers for trades for other synth-DIY-related
stuff of roughly equal value: other CGS boards, other non-CGS module boards,
etc. Of course, acceptance of such a trade is entirely based on my
idiosyncratic tastes.

Thanks for your attention.

--Adam

--
Adam Schabtach
adam@...

Re: CGS48 - VCO -- some questions

2006-03-10 by Jan-Ahrent Czmok

On 09.03.2006, at 04:59, c10h14no2i wrote:
Show quoted textHide quoted text
> I can answer two of your questions...
>
>>
>> 2)
>>
>> How do i need to connect the POT ? Middle Pin goes to CV (right
>> beside the PLS connector), left pin to jacket and right pin to
>> Ground ?
>> Info: Pot is 100Klin, so as all pots are.
>
> the CV1 and CV2 inputs on the pcb are for the processor section.
> Those jacks connect directly to the PCB w/out going through a pot.
>

> The processor pots both connect to "pcw" and "pccw" The middle of
> processor pot 1 connects to "pw1", and middle pin of processor pot two
> to "pw2"
>

okay, will try that.

> If you were wiring up a pot for FM or something, then you would wire
> the right to ground, left to the jack and middle to the PCB
>

Got that, that works now.

>>
>> 3)
>>
>> COARSE/FINE. have a TUNE input and 2 pots (both 100klin). How do
>> those get connected ?
>> cause i got a "Tune" connector on the PCB and 2 pots.
>
> For both tune pots you connect the left ends to the positive and right
> ends to negative supplies (when looking at the back of the pot w/ pins
> down). The middle of the main tune pot goes to "tune" on the pcb.
> The middle of the fine tune pot goes to "cvsn" on the PCB, but you
> have to put it through a high value resistor. 4 to 10m.

Hum, will try that tomorrow -- i just finished the whole cabling
stuff (except the "Waveshape Pot", where i am puzzled up, where to
connect it..

middle pin to PCB (SPW)
left side (CCW) to Ground
right side (CW) to SP+

am i right with this assumption ?


Not to forget ... i still have the "have-to-touch TL072" thingie
before the VCO works, anybody got a _good_ idea of that ? it works
after touching,
even CV works (was using FM AC instead of CV, because CV is not wired
100% right ..

Thanks again for any help -- i think i've got good waymarks to the
final end :-)

--jan

Re: CGS48 - VCO -- some questions

2006-03-10 by c10h14no2i

> i just finished the whole cabling
> stuff (except the "Waveshape Pot", where i am puzzled up, where to
> connect it..
>
> middle pin to PCB (SPW)
> left side (CCW) to Ground
> right side (CW) to SP+
>
> am i right with this assumption ?
>

yes, if you are looking at the back of the pot w/ the pins facing up.
I wire mine w/ pins facing down, so I have to think of it in reverse.
CCW right, CW left


> Not to forget ... i still have the "have-to-touch TL072" thingie
> before the VCO works, anybody got a _good_ idea of that ? it works
> after touching,
> even CV works (was using FM AC instead of CV, because CV is not wired
> 100% right ..
>

For the tl072, if you've double and trippled checked all of the
components in that part of the circuit, I'd just replace the 072. Its
hard to say if could be the one on the bottom left or the top left.
The pro sp trimmer connects to the tl072 on the top left. And if
you're getting CV's and FM to work, then the one on the bottom left
might be good. I'd replace both of them.

(I had one module that didn't work, which had 4 ic's.. One IC smoked,
another got hot. I checked all the components again and again,
re-heated all the solders. I replaced the IC that smoked.. It fried
again. I replaced that IC as well as the one that got hot. The IC
fried again. I checked all components again and again.. finally
replaced all 4 IC's and it worked!)
Someone who knows what they are doing might have a more direct answer.

Re: For sale/trade: CGS Bi-N-Tic PCB

2006-03-11 by nihiliste9@aol.com

hi, id love to buy your board. let me know when and ill paypal you the money. edward

me: edward schultheis
ordeish@... (paypal email)


-----Original Message-----
Show quoted textHide quoted text
From: Adam Schabtach <adam@...>
To: cgs_synth@yahoogroups.com
Sent: Thu, 9 Mar 2006 15:54:57 -0700
Subject: [cgs_synth] For sale/trade: CGS Bi-N-Tic PCB


Greetings,

I have a Bi-N-Tic PC board that needs a new home. Due to changing whims and
interests I doubt that I'm going to use it. It is in like-new condition, as
received from Ken. I'll throw in the paper copy of the Bi-N-Tic web page I
ran off on my printer.

I'll mail it within the United States for $10. PayPal would be dandy but
other forms of exchange are probably okay, too. I'd really rather not ship
it overseas because I don't like standing in line at the post office.

Alternatively, I'll entertain offers for trades for other synth-DIY-related
stuff of roughly equal value: other CGS boards, other non-CGS module boards,
etc. Of course, acceptance of such a trade is entirely based on my
idiosyncratic tastes.

Thanks for your attention.

--Adam

--
Adam Schabtach
adam@...




The CGS Modular Synth home page: http://www.cgs.synth.net/

Yahoo! Groups Links






[Non-text portions of this message have been removed]

Re: For sale/trade: CGS Bi-N-Tic PCB

2006-03-12 by c10h14no2i

I just want to say again how great the bi-n-tic is!! Ive been trying
NOT to patch it in, but I have so much fun with it, it keeps getting used.
Lately Ive been putting an unmodulated VCO, just making a tone, into
its input, then putting my 1v/o signal into the bi-n-tic. Sometimes
it sounds like its trying to talk :).
Show quoted textHide quoted text
--- In cgs_synth@yahoogroups.com, nihiliste9@... wrote:
>
> hi, id love to buy your board. let me know when and ill paypal you
the money. edward
>
> me: edward schultheis
> ordeish@... (paypal email)
>
>
> -----Original Message-----
> From: Adam Schabtach <adam@...>
> To: cgs_synth@yahoogroups.com
> Sent: Thu, 9 Mar 2006 15:54:57 -0700
> Subject: [cgs_synth] For sale/trade: CGS Bi-N-Tic PCB
>
>
> Greetings,
>
> I have a Bi-N-Tic PC board that needs a new home. Due to changing
whims and
> interests I doubt that I'm going to use it. It is in like-new
condition, as
> received from Ken. I'll throw in the paper copy of the Bi-N-Tic web
page I
> ran off on my printer.
>
> I'll mail it within the United States for $10. PayPal would be dandy but
> other forms of exchange are probably okay, too. I'd really rather
not ship
> it overseas because I don't like standing in line at the post office.
>
> Alternatively, I'll entertain offers for trades for other
synth-DIY-related
> stuff of roughly equal value: other CGS boards, other non-CGS module
boards,
> etc. Of course, acceptance of such a trade is entirely based on my
> idiosyncratic tastes.
>
> Thanks for your attention.
>
> --Adam
>
> --
> Adam Schabtach
> adam@...
>
>
>
>
> The CGS Modular Synth home page: http://www.cgs.synth.net/
>
> Yahoo! Groups Links
>
>
>
>
>
>
> [Non-text portions of this message have been removed]
>

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