Before this MFJ-259 was given to me, I did everything antennas the hard way. Thanks, Natan. After I acquired the grid dip coils and some other accessories for it, it became an RF version of the Swiss Army Knife.
I do not favor the version which has UHF. I read online that failure to set a switch and provide a load could damage the UHF section. Since I do not do UHF antenna work with an antenna analyzer, I favor the HF to 2 meter version I have.
This antenna analyzer was given to me non working, but the donor knew I was a tinkerer. I bought the meter I neededfrom MFJ and followed the directions on W8JI website to calibrate it. I will post pictures of unusual ways I use it as they occur.
There is so much information out there, I will not duplicate it here. Go to the source, W8JI.
This is much bigger than an Autek, and therefore harder to carry up a ladder to attach at the feedpoint. Some of the posts to eham comment on QC problems with the Autek. I hope they have corrected the Autek manufacturing, since it is a capable tool also.
But it is a fantastic tool for anything RF. For instance, to set the taps on a tank coil in a big RF amp, attach the analyzer to the output connector. With the RF amp power removed, and a carbon resistor the value of the calculated RF plate load, optimize the SWR looking back into the amplifier with the tuning capacitors set to the calculated values by selecting the coil tap position. This takes into account all the circuit stray capacitances and inductances. Want to check your plate choke for unwanted resonances? Use the grid dip coil to explore the range of frequencies the amplifier will operate on. WOW what fun!
[Pictures coming soon]
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