XTAL - crystal
Q1 - 2N3053
Q2 - IRF510
R1 - 100,000 ohms
R2 - for 3.9 MHz 100 ohms, for 7 MHz 68 ohms.   .5 watt rating.
R3 - 2200 ohms, but anything from 1k to 10k is OK here.
R4, R6 - 10 ohms
R5 - 470 ohms.   ( adjusts gain of modulator )
R7 - 1000 ohms
R8, R9 - 1000 ohms
R10, R11 - 100 ohms
C3 - .01 µF disc
C4 - output shunt capacitor. for 3.9 MHz; 680 to 1000 picoFarads, 100 V.,   for 7.2 MHz; 470 picoFarads, 100 V.
C5 - 1200 picoFarad, silver mica, 100 V.,   But a compression trimmer capacitor
    that covers up to around 2000 pF is best, for tuning up.
C6 - 47 µF, but anything from 10 to 470 µF is OK here, 3 volts or greater rating.
C7 - .01 to .1 µF disc ceramic
C8 - .1 µF disc ceramic
C9 - .1 µF disc ceramic or film, mounted close to the junction with T1 (also, add one near the junction with L1 )
C10 - 100 µF electrolytic, with at least a 15 Volts rating.
C11 - .047 to .1 µF
C12 - 1000 µF electrolytic, with a 12 volt or greater rating.
C13 - 2.2 µF, but anything from 1 to 4.7 µF is OK.
C14 - trimmer capacitor or small variable inductor, to change frequency a little.   Or a fixed value capacitor 22 to 470 pF.
C15 - .1 µF disc ceramic
C16 - .1 µF disc ceramic
L1 - flyback inductor, 24 turns of AWG #20 or 22 on a T50-2 core.
L2 - for 3.9 MHz, 16 turns.   for 7.2 MHz, 11 turns.   AWG #20 on a T50-2 core.
L3 - for 3.9 MHz, 40 turns.   for 7.2 MHz, 23 turns.   AWG #30 on a T50-2 core.
L4 - for 3.9 MHz, 20 turns.   for 7.2 MHz, 15 turns.   AWG #20 on a T50-2 core.
T1 - The modulation transformer was made from a choke core, Radio Shack p/n 270-030A.
  Remove the bobbin, and the wire on it.   Using AWG 20 or 22 magnet wire,
  wind 55 turns, stop and twist for the center-tap, then continue on with 75
  more turns. The end of this winding is +Vmod, going to the transmitter.
  - update: R.S. p/n 270-030A is not sold any more. Use the secondary side of a transformer,
  such as R.S. p/n 273-1512, 273-1511, or 273-1352
U1 - TDA2003