I'm trying to build the LC oscillator show on the bottom of this page for some school project and I'm having a bit of problems translating the theoretical circuit into a real-world one.
Here's the schematic:
I think I get how the circuit works on paper. We have a LC resonant circuit which will produce a certain output frequency. Because the energy in the circuit gets transferred out due to differences between theoretical components and real world components, the transistor is there to keep adding the energy into the circuit. The transistor is controlled by the coupled coil L2 in which we get current induced by the coil L which keeps switching the transistor
For the real world circuit I can use more or less whatever components I want, so my main limitation is that I only have a 1.2 mH 1:1 transformer available.
In some simulations I used that transformer and a \$ 470 \mu F\$ capacitor (I just happen to have one in my drawer) and the expected frequency should be around 212 Hz.
For some reason, the simulations don't seem to be working as expected and I can't figure out why.
For example here's a link to falstad circuit simulator and it's showing bad connections. I also only get the bottom half of the sinusoid.
In Multisim, I'm getting flat line on the oscilloscope with this circuit:
I don't know how to pick a right transistor for this circuit so I just took 2N2714 randomly.
Here's my question: How do I figure out why this doesn't simulate well and how do I determine what I need to look for when picking a transistor for the circuit?
UPDATE Here's a new link for falstad simulator and it's an improvement. I'm still not getting expected oscillations from it though.