Two transmitting circuits

[ppmao]

here is two transmitting circuits all use 315, kind for you to tell me the difference and each their theory.'

[sarma]

Hai,
To my little knowledge, i feel

A. the first circuit is oscillator with antenna directly coupled to it. The whole of oscillator is switched at its emitter by the second transistor.The oscillator is either ON or OF depending on the other transistor's status.

B. The schematic at the bottom, the 3356 is always on and out put is picked up at its emitter. this signal is fed to base of second transistor.
as the 1/0 signal is applied , the second transistor would amplify and transmit through the Antenna. at times it is possible , depending on the AC energy level at emitter of 1st Transistor, the second one may be switched during positive peaks of the ac input signal. the only way to stop this is to earth the base of the second Transistor thro' 1/0 pin input.

ofcourse i did not deal with the type of oscillator configuration, as this could be evaluated by you.
All the best

Sarma