ke8qzc:~/projects/filter
I needed to build a bandstop filter against local FM broadcast band to make my RTL-SDR have fewer imaging issues. It took 6 tries before I got a decent one. I followed the one from LNA4ALL here. The next step is to build it into a box for better sturdiness -- currently attempt 6 likes to fall apart and need resoldered.
Attempt 6 The extra wire coming out of the SMA connector is to feed my RTL-SDR for HF frequencies.
![](./img/filter6.jpg)
Attempt 5
![](./img/filter5.jpg)
Attempt 4
![](./img/filter4.jpg)
Attempt 3
![](./img/filter3.jpg)
Attempt 2
![](./img/filter2.jpg)
Attempt 1
![](./img/filter1.jpg)