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CGS89 ticks on pulse out

CGS89 ticks on pulse out

2017-02-23 by andrew buscher

Hello All. My CGS89's pulse outs have a very short "ghost pulse"after the main pulse.
This occurs in both the A&B outs. It's the same height as the main pulse do it does trigger things. I've swapped the 4017 & 4081s with no change.
Any ideas anyone?


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Thank You
-Hans Buscher
310-776-0143 text






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

Re: CGS89 ticks on pulse out

2017-02-23 by Ken Stone

Did you use a TL072, or did you substitute it for another chip?
Show quoted textHide quoted text
On Thu, Feb 23, 2017 at 10:12 AM, andrew buscher hansbuscher@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

Hello All. My CGS89's pulse outs have a very short "ghost pulse"after the main pulse.
This occurs in both the A&B outs. It's the same height as the main pulse do it does trigger things. I've swapped the 4017 & 4081s with no change.
Any ideas anyone?

----------

Thank You
-Hans Buscher
310-776-0143 text

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




--
Ken Stone otherunicorn@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>

Re: CGS89 ticks on pulse out

2017-02-23 by andrew buscher

Thanks for the reply. I have a TL074CN.
Is this propagation delay?

Thank You
-Hans Buscher
310-776-0143 text


On Feb 22, 2017, at 8:10 PM, Ken Stone otherunicorn@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

Did you use a TL072, or did you substitute it for another chip?

On Thu, Feb 23, 2017 at 10:12 AM, andrew buscher hansbuscher@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

Hello All. My CGS89's pulse outs have a very short "ghost pulse"after the main pulse.
This occurs in both the A&B outs. It's the same height as the main pulse do it does trigger things. I've swapped the 4017 & 4081s with no change.
Any ideas anyone?

----------

Thank You
-Hans Buscher
310-776-0143 text

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




--
Ken Stone otherunicorn@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>

Re: CGS89 ticks on pulse out

2017-02-23 by Ken Stone

I suspect it is some sort of delay. I'm not sure where it is creeping in, though. Check the transistor feeds power to the chips. If there is a bad connection, or it is in backwards, those chips would be current-starved. Also try adding decoupling capacitors directly between the power pins of the chips, as well as a 10uF between the emitter and ground.
Show quoted textHide quoted text
On Fri, Feb 24, 2017 at 6:43 AM, andrew buscher hansbuscher@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

Thanks for the reply. I have a TL074CN.
Is this propagation delay?

Thank You
-Hans Buscher


On Feb 22, 2017, at 8:10 PM, Ken Stone otherunicorn@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

Did you use a TL072, or did you substitute it for another chip?

On Thu, Feb 23, 2017 at 10:12 AM, andrew buscher hansbuscher@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

Hello All. My CGS89's pulse outs have a very short "ghost pulse"after the main pulse.
This occurs in both the A&B outs. It's the same height as the main pulse do it does trigger things. I've swapped the 4017 & 4081s with no change.
Any ideas anyone?

----------

Thank You
-Hans Buscher
310-776-0143 text

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




--
Ken Stone otherunicorn@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>




--
Ken Stone otherunicorn@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>

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