MFJ-974B - Balanced Line Tuner - 300 W 6-80M

The MFJ-974B is a fully balanced true balanced line antenna tuner.

For decades, the Johnson Matchbox has been the standard of comparison for balanced line tuners. But, it had a severely limited matching range and covered only 80, 40, 20, 15 and 10 Meters. The MFJ-974B is its successor. It meets todays needs and even surpasses the Johnson Matchbox outstanding performance.

The MFJ-974B gives you excellent current balance, very wide matching range(12-2000 Ohms) and covers 10-80M continuously including all WARC bands. Handles 300 Watts SSB PEP and 150 Watts CW.

Tuning is fast and easy - - just three tuning controls. You can even adjust for highly efficient broadband low-Q operation or use higher Q when you encounter extreme loads.

The MFJ-974B tunes any balanced lines including 600 Ohm open wire line, 450/300 Ohm ladder lines, 300/72 Ohm twin lead - - shielded or unshielded.

The MFJ-974B is a fully balanced wide range T-Network using four gear driven 1000-Volt air variable capacitors and high-Q air wound tapped inductor for 80-10 Meters and separate inductor for 6 Meters. The tuning components are mounted symmetrically to insure electrical balance. A 1:1 current balun is placed on the low impedance 50 input side to convert the balanced T-Network to unbalanced operation.

Keatures/Specifications:

• 10-80M
• Handles 300W PEP, 150W CW
• Fully balanced 'T' match network
• 1:1 current balun
• Cross needle SWR/Wattmeter 30/300W ranges
• Matches 600 Ohm open wire, 450, 300 Ohm ladder lines, 300/72 Ohm twin, coax & random wires
• High-Q air wound tapped inductor
• 4 gear 1000V air variable capacitors
• 3 tuning controls
• 12V DC illuminated meter
• Size 190 x 152 x 203mm approx.