That calculation does not allow for the base emitter voltage of the transistors.
For instance: RE = VHT / IE should be RE = (VHT - Vbe) / IE

If that's the case then my thresholds should be ~1.06 volts and ~2.73 volts, but they are not.

 

If that's the case then my thresholds should be ~1.06 volts and ~2.73 volts, but they are not.

I didn't go through all the formulae. I expect there are other errors.

 

Then what equations should i use for finding the appropriate resistor values?

 

How about this: http://www.johnhearfield.com/Eng/Schmitt.htm

 

How about this: http://www.johnhearfield.com/Eng/Schmitt.htm

The equations are the same...

 

bump, still having threshold problems.

 

Have look here
https://forum.allaboutcircuits.com/...angle-wave-generator.89450/page-3#post-664936

Or this circuit


You can remove D1, D2, D3 and the Buzzer.

 

Have look here
https://forum.allaboutcircuits.com/...angle-wave-generator.89450/page-3#post-664936

Or this circuit
View attachment 127884

You can remove D1, D2, D3 and the Buzzer.

Correct me if i'm wrong but i'm seeing a low threshold of ~1v and a high threshold of ~3.1v. I'm looking for ~1.66v and ~3.33v.

 

Can you tell me why do you need sucha a "specified" threshold voltage?

 

Can you tell me why do you need sucha a "specified" threshold voltage?

The difference between the low threshold and 0v needs to be the same as the difference between the high treshold and vcc (5v) so the duty cycle of the oscillator is correct, i just chose 1.66 and 3.33 to match the ne555 timer chip.
Vlt ≈ Vcc - Vht