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With VHF circuits it's very hard to adjust properly, because your body becomes part of the tuned circuit while adjusting, but with a little patience, you can get it right. First thing you gotta do is, to figure out how to scope the output at this high frequency. Scoping the AC output is hard, laborious, and asks for specific tools, like high frequency oscilloscope, special probes and can still give a false result. So you can just convert the AC output to DC and scope the peak voltage of the wave. The circuit here shows a high frequency rectifier, at the output of which you put an analog DC voltmeter. While measuring the output you start adjusting all trimmer capacitors in the circuit. Once you get the output to read the highest possible result on the scale, you back off a meter or two to stop influencing the circuit and check the reading from distance. If you've got it right, you can substitute the dummy load with a real antenna and make the readjustments. If your body capacitance has really influenced the circuit you readjust again, back off, check the result again and do this a couple of times till you get it right. Once you're satisfied with the tuning, you encase the circuit, check the result one more time (it might drift off after encasing a little) and if everything's ok you can start using your circuit.
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