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Hi,

I have the below colpitts working at around 100 Mhz as expected in 'Every Circuit' on android. The circuit relies on the BC337 junction capacitances as part of the LC feedback - Every Circuit doesn't model junction capacitance so I just copied the spice parameters from circuit lab as discrete capacitors and that worked. Can anyone confirm that circuit lab actually includes the junction capacitance in the simulation?

In Every Circuit you need to 'add noise' to get the oscillation going, but I have other colpitts circuits working in Circuit Lab without simulating noise and if I change the bjt to 2n2222 I get a simulated output with the attached circuit - albeit a lopsided one.

Can anyone advise? I feel this should work, but that I might be missing something. To get this working in circuit lab would really make our project a lot easier to share with others (teaching scenario)

https://www.circuitlab.com/circuit/hvc9bj/niftymitter/

Thanks,

Ross