For sometime I have had a MFJ-259B that I had purchased from an SK estate. I have treasured the device for a number of reasons. I knew what I had paid for the device was helping that ham’s family and I felt like I needed to honor his memory by using the analyzer. Use it I did! KB5NJD even helped me mod it so it would give us readings down to 470 kHz and I could tune my 630M antenna. As my knowledge has improved, I came to find that there are a lot of things this model of antenna analyzer does not do and that made me think about getting a different device.
One: It doesn’t resolve the sign of X. i.e. is my load inductive or capacitive? W2AEW has a great video on how you can actually resolve the sign of X using a smith chart using an MFJ 259B style analyzer.
Two: The oscillator in the machine is not particularly stable in my opinion. i.e. what freq I was measuring was in doubt by up to 20hz. This isn’t a deal killer for measuring impedance in the field, but is frustrating in a lab environment.
Three: The freq. knob is too sensitive in my opinion. I suppose it makes sense given the tuning range within each band the analyzer covers, but I wanted a little more precision.
Four: All it provides is Freq (approximate as noted above), SWR, R and X (unresolved whether it is positive or negative.)
Again — As a new amateur, it is perfectly adequate as an antenna analyzer. But I wanted something a bit more capable. As it turns out a friend has an AA-600. He was showing me his conventional transformers and how he could measure the frequency response with the AA-600. Not only will it define the sign of X, this thing draws a Smith Chart. It will auto sweep over the entire spectrum of the oscillator enabled on your machine. You can do live measurements where it will show you the rectangular format of impedance and the vector form of impedance. This is a genuine scientific instrument.
Now the question is what frequencies should I cover? I genuinely only have an interest in HF, BUT satellite contacts are interesting. . . and I’ve recently started doing some VHF fox hunts with a local club. At some point I’d really like to build some kind of 2M yagi. If I was doing satellite contacts, it would be ideal to have a 440 beam as well, but the cost differential and the likely hood I would ACTUALLY build such a thing. . . I’ll probably just by a satellite antenna, it’ll be close enough. 🙂
If I decide I really want to experiment at 440 MHz I can always up grade later.
I’m a relatively new ham. Got my license, joined a club and I’m having fun! I enjoy CW, pedestrian mobile, backpacking, and I dream of building radios at some point. At present I have a wife and daughters so my building time is limited.
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