The aerial is a few inches of wire. Lengths of wire greater than 2 feet may damp oscillations and not allow the circuit to work. The two 82pF capacitors in series have a capacitance of 41pF. This gives a resonant frequency of about 101.7MHz. Some adjustment is possible by squeezing or expanding the coil. If you prefer a tunable transmitter than the other transmitters are better suited to your needs.
Although RF circuits are best constructed on a PCB, you can get away with veroboard, as long as you are careful with the design. The coil and C4 and C5 need to be near each other and any long tracks need to be cut, otherwise they may add parasitic capacitance.
A turns calculator is available on my tuned circuit page.
One final point, don't hold the circuit in your hand and try to speak. Body capacitance is equivalent to a 200pF capacitor shunted to earth, damping all oscillations. I have had some first hand experience of this problem. The frequency of oscillation can be found from the theory section,and an example now appears in the Circuit Analysis section.
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