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Subject: Re: [motm] new 'scope owner...

From: Ben Stuyts <ben@...>
Date: 2007-03-24

Hi Rob,

On 24 Mar 2007, at 11:03, rob wrote:

Is there a way of displaying an ADSR output on a basic analog scope? (no storage facilities)

So I can measure time periods and check envelope linearality/expo..


That is kind of tricky because of the slow nature of the signal. First, you must have a repeating trigger on the ADSR, so hook it up to an LFO or something like that, maybe at 0.2 Hz or so. You'd probably want to set your time base to ca. 0.5 or 1 s/Div so you can view the whole envelope from start to end. Next, as Richard mentioned in his excellent post, triggering is crucial. Make sure the scope is not set to some sort of auto-trigger mode, but triggers exactly once on each rising edge of the ADSR. A scope usually has a separate trigger input. You might get a more stable picture if you hook up the trigger of the scope to the gate or trigger input of your ADSR.

Some scopes have some persistancy in their screen. If you turn down the surrounding lights, you might be able to see a ghost of where the waveform was.

Hint: make your own storage scope with your digital camera set to 5 or 10 s exposure time...

With kind regards,
Ben