Finding R2 and R3 values in UJT circuit

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guys i want to find values for R2 and R3 in following circuit diagram.is there any equation or method i can use to find this two values? (i was able to calculate R1 and C)
thanks
 
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  • Circuit schematic of a unijunction transistor relaxation oscillator with +VBB supply at top, R1 and capacitor C in series on the left, and R2 and R3 on the right, with emitter connected to the R1-C junction and bases to R2 and R3 down to ground 0.
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aruna1 said:
guys i want to find values for R2 and R3 in following circuit diagram.is there any equation or method i can use to find this two values? (i was able to calculate R1 and C)
thanks
You want to find values for R2 and R3 such that what conditions are satisfied?
 
i'm trying to sesign a UJT oscilator to fire a triac so i can use it as a dimmer.there are no conditions given.
and after finding R2 and R3 how to calculate peak voltage across R3?
 
Ah, sorry I must have misread it then. Can't help you out here, hopefully someone else will be able to.
 
aruna1 said:
i'm trying to sesign a UJT oscilator to fire a triac so i can use it as a dimmer.there are no conditions given.
and after finding R2 and R3 how to calculate peak voltage across R3?

I'm not up on UJTs. Why would that circuit oscillate? Where is the positive feedback?