Naseemsha said ‘sir. This circuit works well. But its volume is very low.’ There are some serious concerns about this circuit, look at the following quotes:

R6 and R7 are ‘cut short to ground by the capacitor of 100N between the cold end of the tank circuit L1/VC1 and the ground. Because it has a very low impedance for the RF signal..’ (preceding is a quote from ‘DrM’)

‘And even if the “fedback RF” was not shorted to ground thru the cap, it still would not really be a regen. The Output would be fedback out of phase, because it is taken from the collector and fed back to the base(of the darlington) without any phase shifting components between. To get in-phase feedback would require either:

taking the output from the emitter instead of the collector.

OR

placing a phase shifting component(a capacitor perhaps) between the collector output and the base input.

Its actually a good thing that 100nf cap shorts any RF because otherwise it would be DE-generative!’ (preceding is a quote from Ham-er)

Go to http://www.theradioboard.com/rb/viewtopic.php?t=2498 for all the discussion about this circuit.