How to measure Terrestrial TV signals level ?

[overflow]

Good evening,

I'd like to design a circuit to measure the terrestrial TV signal level (measured in dbµV) on a display. As you well know, this is a function available on a TV Field Strength Meter.

This circuit must allow you to select the TV channel (frequency) so you can then measure the signal level at that frequency

Have you some idea on how to implement it by using a PIC controller ?

Regards,
Overflow

 

[Borber]

It's of no consequence using PIC. Such measuring instrument must have TV tuner and IF amplifier with IF level detector. Role of PIC should be a selection of TV channel (over I2C) and displaying signal level on LCD.

 

[overflow]

You are 100% right. The suggestion of to use a PIC was of course related to control section of this circuit. I found this usefull link:

**broken link removed**


In figure 13 you can see the basic blocks of a level meter. Do you know some dedicated schematic or IC to implement the IF amplifier/detector ?

Thanks

 

[Borber]

You can manage the problem by using tuner-IF section of a TV receiver. It has I2C for channel selection and IF section with video and sound demodulators. IF amplifier-demodulator chip has AGC pin which gives a voltage proportional to antenna signal and it can be used for signal level measurements.