I am working on a beat frequency oscillator metal detector. The rest of the project is working properly. The mixer, filter, daq modules, and such.
I can't manage to get this oscillator working. It is a simple oscillator. The only difference on the other one to produce the frequency is I wind my own coil. Neither of them oscillate at all. Any ideas or something to try to change. Schematic of one oscillator attached.
An obvious ommission is the decoupling capacitor on the base of the transistor - it's not likely to work without that (I'm assuming you have a decoupling capacitor across the power rails?).
Try something like 0.01uF, it's also vital in all circuits to have decoupling capacitors across the supply rails, try a 0.01uF and a 100uF in parallel (an electrolytic is VERY important on battery powered items).
It turns out I just use the ".tran 0 20m" .op command the circuit does not seem to oscillate. See image. However, it oscillates normally after I added the extra parameters similar to yours.
Why would ".tran 0 20m 0 1u" make such a big difference?