What's amazing to me is that you can buy a device called a NanoVNA for $300[1], which will test transmission lines from 50 Khz to 4 Ghz, with a remarkable degre

What's amazing to me is that you can buy a device called a NanoVNA for $300[1], which will test transmission lines from 50 Khz to 4 Ghz, with a remarkable degree of precision. This used to be the domain on instruments costing $20,000 and up. I myself have a knock-off that goes to about 1 Ghz and was even cheaper, and it was quite instructive in helping me get a feel for reflections, etc... and came in handy installing some SMD capacitors in the right places on a 100 Watt UHF amplifier for the 440 Mhz band. A few mm of movement made all the difference in the world in terms of matching. [1] https://nanorfe.com/nanovna-v2.html https://nanorfe.com/nanovna-v2.html