Help me to find values for this UJT circuit

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The discussion focuses on determining the values for resistors R2 and R3 in a UJT oscillator circuit designed to fire a triac for dimming purposes. The original poster has successfully calculated R1 and the capacitor but seeks guidance on R2 and R3 without specific conditions provided. There is a query about how to calculate the peak voltage across R3 after determining its value. Participants express uncertainty about the circuit's oscillation capability and the presence of positive feedback necessary for oscillation. The conversation highlights the need for additional information or conditions to accurately calculate the desired resistor values.
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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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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.
 
ok thanks
 
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?
 

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