MFJ-939 (MFJ-939I) Autotuner, 200W SSB/CW, Configured For Icom
Cosmetically this is super clean, and works as it should. Comes as shown in the photos.
The manual is available for free download on MFJEnterprises.Com. Be SURE to download the manual, as the operating instructions are invaluable to the radio operator. Also, it contains information on how to use this same tuner with Yaesu or Kenwood radios. The modification is really simple, in most cases it's change a jumper inside and use a different cable to the radio.
In "MFJ talk", this tuner, as configured, becomes an MFJ-939I (I for Icom). It is designed to work with Icom models such as Icom IC-706, IC-707, IC-718, IC-725, IC-728, IC-736, IC-738, IC-746, IC-756, IC-7000 and compatibles.
The manual also lists the Yesu and Kenwood models this will work with, when the user changes the jumper and follows any other instructions the manual lays out.
This particular tuner is so clean that, except for two tiny paint chips along one edge, it could pass for new. But, it is used. The Icom cables included are new, direct from MFJ.
Here is what MFJ says about this tuner on their website:
Plug & Play! You won’t even know it’s there . . . MFJ-939I/K/Y automatically tunes your antenna as you tune your radio. SWR is just always low.Tunes your coax fed or random wire antennas 1.8-30 MHz from 2 Watts QRP to full 200 Watts SSB/CW.
Matches 6-1600 Ohms (SWR up to 32:1) -- that’s a 50% wider matching range than competing products that are less capable and higher priced . . . and it’s made in the USA.
As you’re ragchewing, contesting or DXing, the MFJ-939 is learning your antenna and the way you operate and storing all this in its 20,000 memories. The more you use it, the more it learns.
MFJ-939 uniquely measures your antenna’s complex impedance (R, X), computes the L-network and snaps in needed components for instant matching.
AdaptiveSearch determines a sub-set of all solutions that can provide a safe match and searches only that subset giving
you an ultra fast match. Others search slowly through all solutions.
InstantRecall first checks its memory to see if you have operated this frequency before. If so, tuning is instantaneous and you’re ready to go!
MFJ exclusive VirtualAntenna Memory system gives you 8 antenna memory banks of 2500 memories each. You can use an antenna switch to select up to 8 antennas and assign each antenna its own 2500 memories!
MFJ has 256 values each of capacitance and inductance for 131,072 matching solutions giving you a finely tuned very low SWR. That`s 4 times the 32,768 solutions of competitors using only 128 L/C values each!
An Audio SWR meter beeps when SWR <1.5, 2, 2.5, 3. Alarms if >3. Audible & Visible Diagnostic messages.
Heavy-duty L-network: 10 Amp/1000V relays, RF duty silver mica caps won’t burn up. Safe, reliable, continuous 200W SSB/CW.
Tiny 6 1/2W x 2 7/8H x 8 3/8D”. 2.4 lbs. SO-39s, random wire ant. & gnd posts.
Truly Plug & Play! No settings, only one cable to plug in! Order MFJ-939I, Icom; MFJ-939K, Ken; MFJ-939Y, Yaesu. Specify Yaesu: FT-100/450/950/ 857/897/1000MP/9000/2000 or other.
If you get a new transceiver, simply order a new Plug and Play cable.
Super Versatile! Works with ALL older rigs, classic transmitters, Flex, Elecraft, Tentec, QRP, others. Auto tune antenna -- touch tune button on any MFJ-939I/K/Y for any rig.