Magnum K1 AM Broadcast Antenna

Magnum K1
Preliminary Information

AM Broadcast Antenna Package
A New Solution for AM | Made in America

Magnum K1 Antennas are custom-manufactured for your application.

Engineered and hand-crafted in the heartland, the Magnum K1 Antenna offers a new path forward for broadcasters who seek to establish full-time AM service at a fraction of the cost.

On the upper AM frequencies, this new antenna can satisfy FCC standards for radiation efficiency and is capable of a kilowatt of power,* providing many Class B, C and D operators an affordable means of installing a new site on a limited footprint. Only a modest flat area of earth or roof is required. At less than 50' in height, an installation can fly under the radar in many communities. And because the antenna’s design is series-resonant with a matching network, an antenna tuning unit is not needed.

The Magnum K1 Package includes the antenna as well as its mounts, support mast and pole, guy lines, hardware and electronics in a weatherproof cabinet. Options such as a preassembled groundplane, roof installation kit, tuning analyzer and custom engineering support are available.

Installation Requirements

Area Required – 100’ by 100’ flat installation surface comprised of earth or a building roof. The antenna and its supporting mast are installed in the center.

Support Mast – Installable on the ground or on a roof, a pivot and winch allow the 20’ support mast with attached antenna to be raised and lowered for assembly and adjustment without the need to climb or use a bucket truck. A support pipe anchors the assembly to the ground or to a ballasted roof stand.

Separation from Tall Structures – Choose a location where nearby objects taller than the 20' mast are at least twice as far away as they exceed the mast’s height. Example: if a 75’ tower is in the vicinity (75’ – 20’ = 55’) it should be at least 110 feet (55’ X 2) away.

Environment – Installation on properties smaller than 100’ X 100’ may negatively affect performance.

Guy Lines – Four non-conductive guy lines extend from a guy ring at the top of the antenna to the installation surface. These lines also provide support for the antenna’s four capacitive hat wires. A second set of four lines tethered to a lower guy collar provide additional support. The guy lines can be tied to support poles if preferred.

Equipment Cabinet – Contains an impedance matching network, J plugs, lightning arrestor and ground bus. The cabinet is installed at service height on the support pole.

RF Exposure Considerations – A one-meter separation from the antenna meets FCC standards. Fencing is not required with the antenna mounted on the 20’ support mast.

Options

Groundplane – A 50’ radius, 32-element preassembled groundplane can be provided. It may be surface-installed, elevated or buried, fanned evenly.

Roof Installation Kit – Allows installation on a flat roof building without penetrations. Roof pads are provided to prevent damage to the roof surface.

Antenna Package Specifications *

Design	Series-resonant: vertical, whip type, series fed, center loaded, omni-directional with adjustable length, inductor and 4-element capacitive hat. Overall assembly: 5 sections.
Power	Up to 1000 watts carrier with 100% standard modulation. **
Frequencies	900 to 1700 kHz.
Bandwidth	+/- 11.0 kHz (900) to +/- 32.0 kHz (1700) - 1.5:1 SWR; +/- 17.0 (900) to +/- 40.0 kHz (1700) - 2.0:1 SWR. **
Radiation Efficiency	133 to 244 mV/m from 900-1700 kHz at 1km ref 1kw (IDF). ** See graph, right. -->
Length / Weight	Antenna: length 358" (29.8'); weight 47 lbs.
Construction	Aluminum tubing 2.8” dia tapering to 1.0” diameter.
Impedance	10-20 ohms.
Inductance	Maximum 100 uH. **
Inductor Material	Stainless steel tubing, 3/16” diameter.
Inductor Weather Sheath	Acrylic cylinder 9.25" diameter with air circulation vents.
Capacitance	Varies with frequency, adjustable. ** Four spokes tethered to guy lines. Down angle 35 degrees.
RF Input	Input bolt for coax center conductor. Feedline included for coax center conductor.
Guy Lines	Nonconductive lines 0.22” diameter. Two collars provided. Provided on spool. Includes turnbuckles and hardware
Temperature Endurance	-40-+65 degrees C.
Wind Endurance	Greater than 140 MPH with guy lines. ****
Recommended Installation	For earth or flat roof installation surfaces, 100’ X 100’. Antenna tip typically 49.9’ above installation surface; 50’radius–32 element wire groundplane; 8 guy lines (2 sets high and low) anchored at a 70’ radius into the installation surface or support poles.
Included . . .
Support Mast	20’ height above installation surface. Aluminum pipe, two telescoping sections with ground lug.
Antenna Mounts	2 – on antenna mast (top three feet).
Antenna Insulators	2 – plastic with stainless hardware for attachment to antenna mast.
Erection Method	Pivot / Winch for attachment to support pole, included.
Conductive Grease	For antenna assembly.
Equipment Cabinet	NEMA3R weatherproof, aluminum. Contains impedance matching device, lightning arrestor, J plugs, ground bonding bus, Unistrut mounts.
Options . . .
Groundplane	50’ radius - 32 elements fanned evenly. Preassembled. May be buried, surface-mounted or elevated.
Roof Installation Kit	Includes support pole / ballast tray, roof pads, guy anchors. Total system roof weight 2,904 lab – does not exceed 37 lbs psf. Averaged weight across a 100 x 100' installation area: 2.9 psf. **
Installation Tool	Network analyzer to tune antenna and match impedance.
Coaxial Cable	UV-rated outdoor cable, cut to length with PL.259 Connectors attached or loose.

   Footnotes:

       (*) All specifications are subject to change without notice.
       (**) Varies with operating frequency.
       (***) Not included: Roof ballast (blocks, sand bags), wood poles/posts, labor.
       (****) Optional Wind Engineering documentation is available.

A New Solution for Fulltime Use on Upper AM Channels

Related Links

Antenna Comparison Chart

Antenna Siting Recommendations

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