Description
MEF-130-LP Multi-Band End Fed Half Wave Antenna Transformer 56:1 Ratio
Features core equivalent to 2.4-inch ferrite core and very low average Insertion loss ~0.4dB
This is an End-Fed Half-Wave antenna (EFHW) transformer covering 160/10m amateur bands or any frequency 1-30MHz. It transforms high impedance ~2800 Ohms at the end of the half-wave radiator to 50 Ohms and features very low insertion loss. Average insertion loss from 1-30 MHz is ~ 0.4 dB
- NO TUNER is needed!
- NO counterpoise is needed!
- Grounding of cable at the entrance to the home is recommended
- Frequency coverage: 1-30MHz
- Power Handling: 250W I.C.A.S
- 100W continuous in digital modes such as FT8 etc.
- Polycarbonate housing
- Hardware: Stainless Steel
- Connector: Silver/PTFE (Teflon) SO-239
- The MEF-130-LP is used in the following antenna models: EFHW-4010-LP, EFHW-8010-LP and EFHW-7510-LP
The wire length can be calculated by the following formulas:
- Length (feet)= 468/Frequency (MHz) or
- Length (meters)=142.5/Frequency (MHz)
Always cut a wire a bit longer to allow tuning to your desired frequency. Tuning depends on the height above ground and nearby objects. There are so many ways to install the wire and your imagination is the only limit. You can do it horizontally, vertically, sloping, in an inverted “L” shape, Horizontal “L”, in an “inverted “V” shape, etc.
Such an antenna will not need radials and in most cases NO Tuner at all. Be a radio amateur and do some experiments.
Grounding the coaxial cable shield at the entrance to the home is recommended! Long wires tend to collect electrostatic charges (usually when the weather is stormy) which can produce ESD (electrostatic discharge) at the end of your cable and damage your equipment.
The longer wire will give you more harmonic-related resonances, For example, Half Wave wire for 80m or 3.5MHz will give you (8) eight resonances up to 30MHz. The VSWR curve might be a bit different at your location. Always aim to put the wire higher and leave it a bit longer at the end to tune it at the desired frequency. The EFHW instruction manual is available on the FAQ.
John M. –
I’m happy. Bought it at the last moment for Field Day. It was delivered on time. It tuned nicely on the band’s specified. I’m happy.
Cliff L. –
Well built and the case is strong. It survived a recent hail storm that smashed house and car windows with nary a scratch.
Larry C. –