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previous: Mark Hammer Photocells have timing characterist... -- 2/16/2000 6:18 PM

Re: opinions of optoisolators

2/16/2000 9:13 PM
moocow	Re: opinions of optoisolators What about linearity with respect to voltage ? A photoresistor is pretty linear, that is, its resistance does not change significantly with applied voltage. But FETs are well-known for their non-linearity with large signals. When I tried these photo-FETs with a phase shifter, the scope showed significant distortion even with guitar level signals. Maybe I was just unlucky, but has anyone been able to obtain an undistorted phase shift with these components ?

2/16/2000 9:13 PM

moocow

Re: opinions of optoisolators

What about linearity with respect to voltage ? A photoresistor is pretty linear, that is, its resistance does not change significantly with applied voltage. But FETs are well-known for their non-linearity with large signals.

When I tried these photo-FETs with a phase shifter, the scope showed significant distortion even with guitar level signals. Maybe I was just unlucky, but has anyone been able to obtain an undistorted phase shift with these components ?

Replies:

Ed Rembold Guys, Thankyou for the added insig... -- 2/16/2000 11:53 PM