Small TV Modulator Using A Motorola MC1374

How can television modulator be small and simple like this? First, it uses integrated circuit, and the second, any TV modulator is nothing more than amplitude and frequency modulator. This simple circuit employ a Motorola MC1374 integrated circuit to form a small TV modulator.  To protect unwanted interference, this circuit need a shielded box and outboard circuitry.  The coil L1 is 4 turn #22 ga enamel wire, and L2 is 43 turns #36 enamel wire. L3 and L4 are 0.22uH radio frequency (RF) chokes. Here is the schematic diagram of the circuit: