I'd like to create my own function generator someday, and so I've been reading up on VCO's and finally got around to building one the other day.

The VCO I built is described as a "comparator based hysteretic oscillator", a type of relaxation oscillator. Essentially, this circuit, on the wikipedia page for "relaxation oscillator".

I somehow managed to pick values that allowed me to cover the audible range almost perfectly and stuck in a potentiometer for the top right resistor, so it can do about 50Hz - 20kHz +, not sure what the top range is because I don't have a scope but it went beyond being able to hear.

Anyways, how good quality of an oscillator is this kind? Compared to other kinds?

How could I increase the bandwidth? At higher frequencies I guess I suppose slew-rate becomes a major problem?

And can any desired frequency be obtained through frequency division? If so, wouldn't it always make sense to opt for the highest possible frequency VCO and just divide down for a function generator?

These are just a few of the multitude of questions I have.

The VCO I built is described as a "comparator based hysteretic oscillator", a type of relaxation oscillator. Essentially, this circuit, on the wikipedia page for "relaxation oscillator".

I somehow managed to pick values that allowed me to cover the audible range almost perfectly and stuck in a potentiometer for the top right resistor, so it can do about 50Hz - 20kHz +, not sure what the top range is because I don't have a scope but it went beyond being able to hear.

Anyways, how good quality of an oscillator is this kind? Compared to other kinds?

How could I increase the bandwidth? At higher frequencies I guess I suppose slew-rate becomes a major problem?

And can any desired frequency be obtained through frequency division? If so, wouldn't it always make sense to opt for the highest possible frequency VCO and just divide down for a function generator?

These are just a few of the multitude of questions I have.

**I know this isn't really a VCO, it's an RCO, but I care more just about any kind of controllable oscilator**
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