Plug & Play! You won’t even know it’s there . . . MFJ-939I 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.
Highly intelligent, ultra-fast tuning!
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.
Measure & Compute = Instant Match
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 VirtualAntenna™ Memory
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!
4 Times More Solutions and Faster!
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
Don’t be fooled by competing products claiming fast search times — if you have a quarter of the matching solutions, of course, it takes less time to finish but it’s not faster. MFJ’s faster speed comes from advanced technology and software algorithms not from fewer solutions.
Audio SWR Meter
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.
As Small as Your Radio
Tiny 6 1/2W x 2 7/8H x 8 3/8D. 2.4 lbs. SO-39s, random wire antenna and ground posts
Never Obsolete . . . Super Versatile
Truly Plug & Play! No settings, only one cable to plug in! If you get a new transceiver, simply order a new Plug and Play cable.