I had a chance to take a look of a typical analogboard circuit diagram
> of a system having Television Receiving unit.
> There is a tuner front end mounted on the analog board.
> Accoring to circuit diagram, there is the antenna connection into the
> front end module and SIF and CVBS output from it. It is controlled by
> I2C input.
> What I would like to know there is why the front end needs a voltage
> as high as 33V.
** For the "varicap" diodes.
The gizmos that actually tune the RF circuits inside the tuner module.
And I would like to know the I2C control scheme (how it is controlled
> digitally, and what are the parameter that can be controlled in the
> tuner?) of the Tuner Front End Module.
** Operating frequency, switching bands ....
All RF stuff you have not got the faintest about.
....... Phil