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*Must start simulation with switch open and then turn it on*
Originally when I built this on my breadboard using IRFZ44N Mosfets, the maximum obtainable frequency was actually only 44KHz using a 5-6v power supply, and I tried several things to try to fix that, but got no promising results... Well, later on I eventually figured out that it wasn’t at all because it was a bad design (I just knew it had to work like I intended and I really believed in it so I kept trying to figure out what else could be affecting the frequency so drastically).... So, long story short, The gate of the mosfet itself just couldn’t charge up fast enough through the 33kOhm resistor, so I significantly lowered the resistance at the collector of the npn which was driving the mosfet at first to 10K, then 1K, and finally I dropped it all the way to just 100 Ohms, and I have to say, just WOW!! ...Because the frequency had literally jumped straight up from just 44kHz all the way to 940kHz! Amazing the difference that made!!! whereas I was actually kinda thinking the corners of the waveform would be quite rounded if the transistor was even able to have enough gain to sink current to a 100 Ohm resistor, it actually to my surprise held its sharp corners really well at almost 1MHz, and was still able to source a pretty good amount of current without affecting its sharpness. And every circuit doesn’t even show it oscillating below 1kOhm... and that’s completely inaccurate, cause it absolutely does work, and it works very well (using 2n3904 transistors).
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