[sdiy] Ultrasonic VCO question for Ian Fritz (or whoever)

[Ian Fritz]

Magnus --


>The compensation will distort the waveform for higher frequencies but trade
>from waveform accurateness (which is bad to start with due to the reset slope,
>I've seen it and it's not excessively nice) for better tracking abilities.
>What can be a problem is that the compensation leads to a slightly lower AC
>amplitude and raises the DC offset as the frequency raises and compensation
>starts to kick in.


How can you say you say you have "seen it"?  Have you built this circuit? 
Where did you get the schematic if you don't have the EN issues?

Why so you think the DC offset would change?  This is a tri oscillator, so 
I see no reason for the pos and neg half cycles to be affected differently.


>IMHO, this is a fair trade anyway, since few depends on the
>accurate waveform and spectrum distribution about 50 kHz or so.


Plus that, the module only uses the square output (to drive a digital 
waveshaper).

   Ian