o T1 & T2 are BF245 N-channel High-frequency FET's and can be replaced with a NTE133/ECG133. TheECG312 could likely be used also. The varactor diode BA121 can be replaced with a ECG/NTE611. USWstands for 'Ultra-Short-Wave'.o L1/L2 = 7 turns of 0.5mm Silverwire on a 5mm adjustable Ferrit-core.o This very stable oscillator has a frequency of 400MHz and could preferred be a lot higher. At 5V thefrequency is around 137MHz.o Voltage supply is not critical. The oscillator starts working at 3V, the upper limit is given by threshold of theBF245 and is 30V. At 12V sinks at about 5mA.o Feedback via 16pF capacitor. No interference from (dipole) antenna on resonance-loop.o Distance is a minimum of 300 meters (900feet)!

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Micro-Spy with FETS http://www.sentex.ca/~mec1995/circ/uspy.htm

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