Measurment on a Drake TV-75-HP filter

click to enlage the picture.
This hi-pass filter has been designed to protect your TV from the HF signals transmitted by your HAM station. Let's have a look how it can reject the signals under 50 MHz.

The filter's input and output are connected to the 'DUT' and 'DET' miniVNApro SMA ports. The software used for this measurement is vna/J from DL2SBA using the 'transmission mode'.

We can notice the insertion loss over 60 MHz is very low. The signals under 30 Mhz are attenuated at least 70dB.