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CGS88 and TPS

CGS88 and TPS

2015-05-22 by oivind60

I'm using the cgs88 as a Quad bi dir router in my TPS (Dmitri`s TKB) and want leds to indicate the vertical steps.

How can I do that?

Is it a sollution to make a board with three CD4007and connect the SW in parallel with the chips on the board and use the four outs for the leds?


Re: CGS88 and TPS

2015-05-22 by Ken Stone

If you duplicate the switching part of the 88 (or use a second one in parallel), yes, you can select LEDs that way. Or you could use a CD4051 or 4052 to do it too.
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On Fri, May 22, 2015 at 8:25 PM, oeiols@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

I'm using the cgs88 as a Quad bi dir router in my TPS (Dmitri`s TKB) and want leds to indicate the vertical steps.

How can I do that?

Is it a sollution to make a board with three CD4007and connect the SW in parallel with the chips on the board and use the four outs for the leds?





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

Re: CGS88 and TPS

2015-06-01 by oivind60

Now I've got all the chips and tried to run it.
Seems like I have some bleedthrough on both PCB`s.
I´m using one for the vertical steps on the TPS and the other one for the leds. Coupled the other way.
PCB`s are connected together only with power and M/N/O.
I see the leds blinking but two and two together and also the pots somehow are affected of each other two and two.

Re: CGS88 and TPS

2015-06-01 by Ken Stone

Check your BH and CL links on both boards.
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On Tue, Jun 2, 2015 at 4:36 AM, oeiols@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

Now I've got all the chips and tried to run it.
Seems like I have some bleedthrough on both PCB`s.
I´m using one for the vertical steps on the TPS and the other one for the leds. Coupled the other way.
PCB`s are connected together only with power and M/N/O.
I see the leds blinking but two and two together and also the pots somehow are affected of each other two and two.




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

Re: CGS88 and TPS

2015-06-02 by oivind60

The links are ok. I have desoldered the board for the leds too. Nothing.
Before I did that the leds blinking when I moved my hand under the board?
I have tried to measure while steping and have got those results.
LM3900 pin 5: 5,8V alternating -6,8V
4013 pin 11: 7,6V alt -6,9V
4013 pin 13: 7,6v or 5,8v or -6,8v
4007 u4 and u5 pin 3 (sw): alternating 7,6v, 5,8v and -6,8v.
Please help :-)
The vertical mode sort of working but cv from the other pots are bleeding.
And with the leds I didnt use drivers.


Re: CGS88 and TPS

2015-06-03 by Ken Stone

I really don't know what is going on. The voltages you show are indicative of the divider doing what it should.

Are you controlling the LED board 4007s from the 4013 on the voltage switching board? You should be. Does each board have it's own LM3900, or are you sharing the PSU?

For the LEDs, use high brightness types if you can. No driver is needed with them. The input of the switches D should be taken to pin 14 of the lm3900 via a 10k. The switch outputs go to the LED anodes. The LED cathodes go to pin 7 of the LM3900.

Didi you use static handling precautions for the 4007?

Ken




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On Wed, Jun 3, 2015 at 5:00 AM, oeiols@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

The links are ok. I have desoldered the board for the leds too. Nothing.

Before I did that the leds blinking when I moved my hand under the board?
I have tried to measure while steping and have got those results.
LM3900 pin 5: 5,8V alternating -6,8V
4013 pin 11: 7,6V alt -6,9V
4013 pin 13: 7,6v or 5,8v or -6,8v
4007 u4 and u5 pin 3 (sw): alternating 7,6v, 5,8v and -6,8v.
Please help :-)
The vertical mode sort of working but cv from the other pots are bleeding.
And with the leds I didnt use drivers.





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

Re: CGS88 and TPS

2015-06-03 by oivind60

For the leds I´m using only a board with only the 4007 and share psu. I have disconnected this board for now.

And I am using antistatic arm wrist band and a metal plate on my workbench. All earthed.
Maybe I have got bad 4007s. I have got them from Tayda but I have never had any problems with theirs components before.
Is it a way to testing them?
Øivind

Re: CGS88 and TPS

2015-06-03 by Ken Stone

Other than testing the 4007 in circuit, no, there is no easy way. Have a chat to Dmitri and see if he had any similar issues. The TPS is his project after all.
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On Thu, Jun 4, 2015 at 6:14 AM, oeiols@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

For the leds I´m using only a board with only the 4007 and share psu. I have disconnected this board for now.

And I am using antistatic arm wrist band and a metal plate on my workbench. All earthed.
Maybe I have got bad 4007s. I have got them from Tayda but I have never had any problems with theirs components before.
Is it a way to testing them?
Øivind




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

Re: CGS88 and TPS

2015-06-04 by oivind60

I maybe have to live with it for now and when I get time for it I will split the router and test it like a triple router.

Re: CGS88 and TPS

2015-06-08 by oivind60

Tried to isolate them for testing and they still bleeding. But they only bleeds when the pots on the TPS are high. When I use audio they are fine. Dmitri mentioned the problem can be because the voltage is to high.
Can it be a sollution to use the cgs28 as someone has sugested?

Re: CGS88 and TPS

2015-06-08 by Ken Stone

Yes, the 88 has a maximum input of around 7V. You have two choices - limit the voltage that goes into them with a voltage divider, or, as you say, use a CGS28. (connect inputs 1 and 5, 2 and 6, etc.) And it even has it's own LED drivers.

Cheers,
Ken
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On Mon, Jun 8, 2015 at 10:01 PM, oeiols@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:

Tried to isolate them for testing and they still bleeding. But they only bleeds when the pots on the TPS are high. When I use audio they are fine. Dmitri mentioned the problem can be because the voltage is to high.

Can it be a sollution to use the cgs28 as someone has sugested?




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

Re: CGS88 and TPS

2015-06-08 by oivind60

Thanks Ken
Then I will order a cgs 28 next time.
I have a couple of Serge panels in my backlog

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