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MFJ-1899T Whip

MFJ makes a great little multi band, adjustable whip antenna that can be added to your KX2, KX3 or almost any QRP radio. It can be used when the radio is on the table top or even if the radio is used like an HF HT.  The compact size of the antenna, along with some ground radials, make it great for back packers. No trees in site to erect an antenna, pull out your 1899T whip and you are on the air.

The longer of the two radials is my 40 meter radial. No banana jack is shown on the far end of the radial since I had no intensions of using this antenna on 80 meters. 20 meter ground radial not shown.

For ground radials I use #22 stranded, teflon insulated wire. On Ebay, I found male and female mini banana jacks. They not only fit into the socket on the KX2 but also make for a great inline connection on the ground radials. First I made a 15 meter ground radial. I put a male jack on one end and a female on the other end. I then cut another length of wire, to be added to the 15 meter radial, so the two wires in series would be resonant on 20 meters. I then put a male jack on one end and a female on the other end. So one wire alone will work for 15 meters and then couple the two wires and you are good for 20 meters. Next I cut one more length, to be added to the pair, so I can work 40 meters. 

I found that the chart that MFJ provides, for adjusting and using this antenna, is not even close to where the setting should be. To test the antenna, here is what I did.
I made a small table top mount for the antenna and attached elevated radial. I clamped the mount to a wooden picnic table and attached a short length of coax. I put a #43 ferrite choke on the end of the coax at the feed point of the antenna. I next attached a Rig Expert AA-600 antenna analyzer. Using this method I was not only able to determine that the chart provided by MFJ was not even close to what the setting should be, but was able to develope my own settings and ground radial lengths. Below are my findings. 

I printed out that above chart, laminated same and take a copy with me when using the MFJ-1899T.
This antenna along with a KX2 or KX3 makes a great little HT to be used on HF.