Low noise antenna feedline

[g1hbe]

Thanks for going to the trouble to post this Noel, it's all very useful info. Just one point - in a superhet with a 455 KHz IF, the image frequency will be at TWICE 455 KHz above the receiving frequency. This is because the local oscillator will be running at Fsignal + IF and the image response will be at LO + IF. So the image freq will be at Fsignal + 910KHz.