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Sequential Switch - Sequencer

Sequential Switch - Sequencer

2007-09-05 by Andrew

Well I know why my first Sequential Switch did the pop 'n smoke
thing... wrong chips! 4051 isn't 4015 :)

On my "fixed" version, the current step LED takes about 3 seconds to
totally go dark when I remove power. Is that an indicator of something
wrong or is that OK ?

Drew

Re: Sequential Switch - Sequencer

2007-09-05 by sasami@hotkey.net.au

>Well I know why my first Sequential Switch did the pop 'n smoke
>thing... wrong chips! 4051 isn't 4015 :)

That would make a minor difference :)

>On my "fixed" version, the current step LED takes about 3 seconds to
>totally go dark when I remove power. Is that an indicator of something
>wrong or is that OK ?

That is caused by the power supply capacitors and decoupling capacitors
discharging. Quite normal.

Ken


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

Re: Sequential Switch - Sequencer

2007-09-06 by Andrew

One more question (after a long session last night)

I have the eight pots set up with +15v coming in, then out to a 200K
resistor and then on to the I1, I2, I3, etc

Things work properly, *but* there is a voltage "bump" at the upper
end of each pot's range and it seems to leak into the Output. For
example, step #2 is active, the pot set about 50%, +3v coming from
the Output. If I turn step #6 (or #5 or #1) pot clockwise, at the
very end of the range the Output will jump up to ~+3.1v.

Everything is fine if I keep the pots from going to the last 5% of
their clockwise sweep. ????

Drew
Show quoted textHide quoted text
--- In cgs_synth@yahoogroups.com, sasami@... wrote:
>
> >Well I know why my first Sequential Switch did the pop 'n smoke
> >thing... wrong chips! 4051 isn't 4015 :)
>
> That would make a minor difference :)
>
> >On my "fixed" version, the current step LED takes about 3 seconds
to
> >totally go dark when I remove power. Is that an indicator of
something
> >wrong or is that OK ?
>
> That is caused by the power supply capacitors and decoupling
capacitors
> discharging. Quite normal.
>
> Ken
>
>
>
______________________________________________________________________
_
> Ken Stone sasami@...
> Modular Synth PCBs for sale <http://www.cgs.synth.net/>
> Australian Miniature Horses & Ponies
<http://www.blaze.net.au/~sasami/>
>

Re: Sequential Switch - Sequencer

2007-09-06 by sasami@hotkey.net.au

Odd. Exceeding something somewhere? Try adding a resistor in series with the
top end of a pot and seeing if that eliminates it.

Ken
Show quoted textHide quoted text
>One more question (after a long session last night)
>
>I have the eight pots set up with +15v coming in, then out to a 200K
>resistor and then on to the I1, I2, I3, etc
>
>Things work properly, *but* there is a voltage "bump" at the upper
>end of each pot's range and it seems to leak into the Output. For
>example, step #2 is active, the pot set about 50%, +3v coming from
>the Output. If I turn step #6 (or #5 or #1) pot clockwise, at the
>very end of the range the Output will jump up to ~+3.1v.
>
>Everything is fine if I keep the pots from going to the last 5% of
>their clockwise sweep. ????
>
>Drew
>
>--- In cgs_synth@yahoogroups.com, sasami@... wrote:
>>
>> >Well I know why my first Sequential Switch did the pop 'n smoke
>> >thing... wrong chips! 4051 isn't 4015 :)
>>
>> That would make a minor difference :)
>>
>> >On my "fixed" version, the current step LED takes about 3 seconds
>to
>> >totally go dark when I remove power. Is that an indicator of
>something
>> >wrong or is that OK ?
>>
>> That is caused by the power supply capacitors and decoupling
>capacitors
>> discharging. Quite normal.
>>
>> Ken
>>
>>
>>
>______________________________________________________________________
>_
>> Ken Stone sasami@...
>> Modular Synth PCBs for sale <http://www.cgs.synth.net/>
>> Australian Miniature Horses & Ponies
><http://www.blaze.net.au/~sasami/>
>>
>
>
>
>
>The CGS Modular Synth home page: http://www.cgs.synth.net/
>
>Yahoo! Groups Links
>
>
>
>
_______________________________________________________________________
Ken Stone sasami@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

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