Measuring the "FM band stop filter"

 

I quickly tested the MRDDZ BS "band-stop filter." The results weren't satisfactory:

                                        Measuring only the throughpass

                                             Marker 2: 150 MHz 

                   no 2m amateur radio - no AIR-band - no 136 WX satellites ...

                                88,5 MHz: -11,4 dB / 108 MHz: -21,4 dB


 

Broadband loop antenna

The efficiency of this broadband loop antenna is naturally low. The advantage is the broadband nature of the antenna. 

The diameter is 1.2 metres. 

In 40mB the efficiency is too low when transmitting, 30mB and 20mB are okay. From 17mB upwards the diameter is too large. The reception is not so strong but relatively quiet.