In sci.electronics.design said:
I was just about to post and ask you if you had read the data sheets.
The gate resistors are there to spoil the very highest frequency
response of the fets to discourage ringing oscillations every time
they switch that might keep going and destroy the fets with excessive
losses.
Depending on the circuit (things like switching speed and the
amount of power involved), the FET's are not neccesarily destroyed.
The circuit may actually work okay, right up until the time the FCC
comes around looking for whatever it is that's interfering with your
neighbor's broadcast TV reception (there's always one in every
neighborhood who still watches off-the-air local broadcasts instead of
cable/dish/DVD's).
Did I ever fix a legacy design that used mosfets as switches with
no resistors in the gates that worked fine except for grossly
unacceptable RF emissions when this part of the circuit was activated?
No comment...
This circuit isn't used to drive the motor for rotating a TV
antenna, is it? If the circuit is made without the gate resistors, I
could imagine the oscillation being powerful enough to damage the RF
front end of the TV tuner. You certainly wouldn't receive a TV signal
while rotating the antenna.