# UJT firing circuits for SCR

Is it possible to replicate a random pattern of trigger and charge times to an UJT firing circuit for an SCR configuration?

What I mean is that, UJTs usually have a periodic sequence to them. Charging and discharging of the capacitor connected between its E and B1 terminals occurs in a periodic fashion. Now, say the power supply is about 5V and I assigned this the binary value 1 and the binary value 0 to 0V. Since charging and discharging happens in a regular periodic fashion say, 1001001001... Is there a way that a UJT firing circuit can be configured in order for the charging and discharging to occur in say an irregular un-smooth fashion like 0010110011110?

Here's a website that describes how a UJT firing scheme works: http://www.electronics-tutorials.ws/power/unijunction-transistor.html

As you can see, the $$V_{R2}$$ waveform is regular and periodic. What I'm asking is if it's possible to redesign this circuit:

so that it can produce an irregular waveform. Assuming that the high values of$$V_{R2}$$ and $$V_{ON}$$ are 1 and the low values $$V_{R2}=0$$ and $$V_{OFF}$$ are 0. Then can a circuit be designed to produce a firing scheme such as 0010110011110 that repeats itself instead of 1001001001 that repeats after every 100?? So that if you zoom the waveform out, then you can see that repeating pattern though it's not as smooth and nice as the regular 100100100 sequence.

• It is not clear what you are asking. Please provide a schematic (there's a button on the editor toolbar) and explain what you are trying to achieve. e.g., "I want to create a random interval lamp flasher using a random binary data stream of 13.7 bits per second. The power supply is xxx V, the load is an xxxx and the SCR would be something similar to XXyyy." – Transistor Aug 8 '16 at 19:44
• Hey i've changed it can you try to answer? – pkjag Aug 10 '16 at 9:14