I am interested in getting an Antenna analyzer, but have a very limited budget. I saw a Chinese model on Ebay that was under $100 brand new, but after doing some research, it appears that this unit is, to put it mildly, less than stellar in reliability, or performance. I see very few used ones for sale and even then they are pretty pricey. I have even looked into home brew, but it's been an awfully long time since I've done any electronic circuitry work. I went over some of my old notes and books and was astonished at how much I have forgotten. Any suggestions?