MFJ-1778 G5RV Multi-Band Antenna

MFJ G5RV Multi-Band Antenna

• Covers all bands, 160-10 Meters with antenna tuner.
• 102 feet long, shorter than 80 Meter dipole.
• Use as inverted vee or sloper to be more compact.
• Use on 160 Meters as Marconi with tuner and ground. Handles full legal limit power. A
• dd coax feedline -- get on the air!

The G5RV antenna is a multi-band center-fed dipole antenna capable of 1500 Watts.

• It was originally designed to operate as a 3/2 wavelength center fed antenna for 14 MHz, but amateurs soon discovered it would offer reasonable performance on many other bands.
• The MFJ-1778 (G5RV) consists of a 102 foot flat top fed with a 32.5 foot 450 ohm matching section ending in an SO-239 coaxial connector.
• The 450 ohm balanced transmission line serves as a 1:1 transmission line transformer on 14 MHz.
• The SWR is approximately 2:1 at 14 MHz. The same balanced line section acts like a transmission line impedance matching section on the other HF bands.

This antenna generally requires the use of a suitable matching network (antenna tuner) since the SWR of the G5RV is almost certainly not 1:1 on any band. The use of a tuner will guarantee maximum performance from solid state exciters. The G5RV is a balanced antenna that is fed by an unbalanced coaxial line. This feed system causes unwanted parallel RF currents to appear on the shield of the coaxial feedline. A choke type balun should be used with this antenna to eliminate or reduce the undesirable parallel feedline currents. Failure to use a choke balun may result in RFI, RF feedback, or other symptoms of RF "in the shack".

The Balun Requirement section describes how to construct a choke balun for this antenna.