A neat little toy, the Youkits HF antenna analyser, its handy to check the resonance of my antennas’ small, portable and quick!. my version goes from 1-60mhz, and have adjustable tuning control. you can read the manual at http://www.youkits.com/
its pretty simple, and has a built in Li-on battery. this is a version one model, the version 2 model uses a little less power and goes to 72Mhz (not that this makes a difference, no OZ ham band there!)
on the market now days is this though a http://sark110.ea4frb.eu SARK 110 box, 1-200mhz, with more control, my next ham purchase I think. (got to check those 144mhz antennas)..
and this really cool (hf only) KVE-60C device , that has just become available.