![]() You can even adjust for highly efficient broadband low-Q operation or use higher Q when you encounter extreme loads.Ī large three-inch lighted Cross-Needle SWR/Wattmeter lets you read SWR, peak or average forward and reflected power all at a glance on 300 or 30 Watt ranges.Ī ground post is provided to ground one output terminal so you can also tune random wires and coax fed antennas. ![]() Tuning is fast and easy - just three tuning controls. Handles 300 Watts SSB PEP and 150 Watts CW. The MFJ-974B gives you excellent current balance, very wide matching range(12-2000 Ohms) and covers 3.5 MHz through 54 MHz continuously including all WARC bands, 6 Meters and the new 60 Meter band. ![]() It meets todays needs and even surpasses the Johnson Matchbox outstanding performance. But, it had a severely limited matching range and covered only 80, 40, 20, 15 and 10 Meters. It gives you superb current balance throughout its very wide matching and frequency range.įor decades, the Johnson Matchbox has been the standard of comparison for balanced line tuners. If a horizontal dipole is too close to the ground, the lion’s share of your signal will be going skyward at a steep angle.The MFJ-974B is a fully balanced true balanced line antenna tuner. Whichever dipole you finally choose, install it as high as possible. Simply throw it up in the air and let the tuner worry about providing a low SWR for the transceiver. With a ladder line dipole, no pruning is necessary. Wire antennas fed with coaxial cable must be carefully trimmed to render the lowest SWR on each operating band. They enjoy the luxury of turning on the radio and jumping right on the air-without squinting at an antenna tuner’s SWR meter and twisting several knobs.Įven with all the hassles, you can’t beat a ladder-line fed dipole when it comes to sheer lack of complexity. After a year or two of playing tug o’ war with the wind, ladder line will often break.īesides, many hams don’t relish the idea of fiddling with an antenna tuner every time they change bands or frequencies. And ladder line doesn’t tolerate repeated flexing as well as coaxial cable. Unlike coax, you can’t bend and shape ladder line to accommodate your installation. You must keep it clear of large pieces of metal (a few inches at least). Ladder line isn’t as easy to install as coax. So why doesn’t everyone use the ladder line approach? The reason has much to do with convenience. Even so, this antenna is almost guaranteed to work well on several bands, despite the need to retune. You may discover that you cannot achieve an acceptable SWR on some bands, no matter how much you adjust the tuner. (You’ll definitely need to readjust it when you change bands.) (Anything below 2:1 is fine.) You’ll probably find that you need to readjust the tuner when you change frequencies. Just apply a signal at a low power level to the tuner and adjust the tuner controls until you achieve the lowest SWR reading. Ladder line offers extremely low RF loss on HF frequencies, even when the SWR is relatively high. Shorter versions will also work, but you may not be able to load them on every band. ![]() A 130-foot dipole of this type should be usable on almost every HF band. You can make this antenna yourself, or buy it premade if you’re short on time. Use regular coaxial cable between the antenna tuner and your radio. Feed the ladder line into your house, taking care to keep it from coming in contact with metal, and connect it to your tuner. You won’t be trimming or adding wire to this dipole.įeed the dipole in the center with 450- ohm ladder line (available from most ham dealers), and buy an antenna tuner with a balanced output. Don’t worry about the total length of the antenna. These are going to be the two halves of your dipole antenna. Simply cut two equal lengths of stranded copper wire. You can also enjoy multiband performance without traps, coils, fans or other schemes.
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