This transmitter needs heatsink at 2N2219. With the C4 we regulate the frequency. With their C7, C8 we adapt the resistance of aerial (practically to them we regulate so that it is heard our voice in the radio as long as you become cleaner).
C4, C7, C8=0~45pF trimmer
L1=4 turns, 7mm diameter *
L3=3 turns, 7mm diameter *
L4=5 turns, 7mm diameter *
L2=RFC (resistance 1MOhm with wrapped around her inductor of enough coils from fine isolated wire. Scratch of utmost inductor and you stick in utmost the resistance making thus a parallel L-r circuit.)
ANT=Simple dipole l/2.
MIC IN=Microphone dynamic or other type. (It can also connected to a cassette player unit)