Hi, I was looking since some days for a schematic to build a sawtooth and triangular wave generator, then I found this schematic on an online simulator: https://www.falstad.com/circuit/e-555saw.html (I report the original link, obviously, to give credits to the person which has made this schematic), which seems logic and reliable to me. Then I edit this schematic by adding a resistive 47k potentiometer between R4 (10k resistor) and the PIN 7 of the 555 IC, and by the simulation, by adjusting the potentiometer, the circuit is able to give a sawtooth and a triangular wave as reported in these images:
Sawtooth wave
Triangular wave
I would ask: is this configuration Ok? For the transistor Q1 i will use a BD140 PNP (just because I have a handful of them).
I also used it in past on a square wave generator to increase the output current.
Can I also expect to measure in this circuit a gain in the output current, or such transistor would be excessive for the circuit? And in this case, would I have to change the values of resistors?
The need of this circuit which I will assemble is just didactic for me, there is not specific purpose.
Thanks.
Sawtooth wave
Triangular wave
I would ask: is this configuration Ok? For the transistor Q1 i will use a BD140 PNP (just because I have a handful of them).
I also used it in past on a square wave generator to increase the output current.
Can I also expect to measure in this circuit a gain in the output current, or such transistor would be excessive for the circuit? And in this case, would I have to change the values of resistors?
The need of this circuit which I will assemble is just didactic for me, there is not specific purpose.
Thanks.