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Demonstrates the construction of a **multi-band HF mobile antenna** utilizing a modified CB whip antenna base. The resource details the process of stripping a commercial CB whip, winding a new helical coil with 0.7mm insulated copper wire, and identifying tapping points for various HF bands. It emphasizes the importance of a rugged, slim design for mobile operation, discussing mechanical length, power handling (up to 200 watts), and coil diameter considerations. The article includes a graphic illustrating the antenna's operational principle, where sections of the helical coil are shorted from bottom to top to maintain efficiency and high Q. The resource presents a practical approach to achieving **band switching** without an external tuner, by manually adjusting tapping points on the coil. It provides a table with reference lengths in centimeters from the feedpoint for 7 MHz (40m) through 28.7 MHz (10m), including WARC bands. The author details mounting techniques, suggesting a Diamond bracket for secure attachment to a vehicle trunk, and stresses the critical role of proper grounding for optimal performance. The design allows for operation on 75m and 80m bands by adding a 110mm steel whip.

Drawing and assembling instruciton for Slim-Jim 2m Antenna

Details the construction of a J-vertical antenna specifically for the 10-meter band, offering a practical alternative to a _Slim Jim_ design for 28 MHz. The resource outlines the use of aluminum tubing for the half-wave vertical section and coaxial cable for the quarter-wave matching section, providing specific calculations for element lengths based on frequency and coaxial cable velocity factor. It contrasts the performance of the J-vertical with center-fed dipoles and end-fed verticals, noting superior results in previous comparisons. The article further presents a more recent iteration of the J-vertical, constructed using a fiberglass pole and insulated wire, with updated dimensions for 28.8 MHz. It includes practical advice on weatherproofing connections and securing the antenna for durability against adverse conditions, referencing the survival of an original _J Vertical_ during 110 MPH winds in 1987. The SWR performance is reported as 1.1:1 at 28.6 MHz, maintaining below 1.5:1 across 28.3 to 29 MHz.

2 meters copper tube antenna, tested with an Icom IC-V8000

How to make a simple but effective Slim Jim antenna. It includes a calculator to work out all the mesurements for the frequency you require.

How to make a Weatherproof Vertically Polarised Omnidirectional Aerial, The Slim Jim Antenna

G0KYA slim jim antenna for 10 meters band

The slim-jim antenna for 144 MHz

This VHF 145 MHz antenna is easy to build and with no radials. It shows equal gain of 5/8 lambda. It is light weight, you can hang it somewhere (on a tree may be) and work.

Outbacker mobile and portable antenna systems are slim line, highly efficient, single whip multi bond antennas for vehicular and limited space portable applications.

Dutch Antenna and Tower Manufacturers from Slimline Square Triangular Round Towers. Antennas production include Yagi Monoband/Dipole/HF Quad /50MHz and 70MHz Yagi-Quad, VHF-UHF yagi-Quad and Comby antennas VHF/UHF/SHF

G0KYA's Amateur Radio Blog, make a 2m Slim Jim antenna out of 300 Ohm ribbon cable.

A 10 meters band Slim Jim antenna project, made with a 450 Ohm slotted ribbon cable and secured on a 8 m fishing pole, by Steve G0KYA

This 4m Slim Jim Antenna is cheap and easy to build yet it greatly out performs the more usual dipole due to its low angle of radiation. An SWR of 1:1 is obtainable across the 4m ham radio FM band with a simple adjustment.

A vertical monoband antenna design that can work from 6 meters to 70 cm by F5ZV in French

Development of the Slim Jim antenna for HF

2 Meter Indoor Slim Jim Antennas for Cyclone Season and Other Uses by VK4MDX

A Unique VHF Antenna with gain over a J-Pole Jose I. Calderon, DU1ANV

The 2BCX Slim Jim by F.C. JUDD, G2BCX.

An home made slim jim antenna for 2 meters band by VU2TQC

The 2 Meter 146mhz Slim Jim Antenna using aluminum tubing!

2 Meter Slim Jim Antenna Using 300 Ohm Twinlead

K0GKJ project of a copper tube slim jim antenna for two meter band

A 144 Mhz Slim Jim Antenna, aluminum tubing version project by Mohammad 9W2WTF

Build the Slim JIM Antenna, a unique VHF Antenna with gain over a J-Pole Jose I. Calderon, DU1ANV

A Slim Jim Antenna project

A comparative article on performance differences between Slim Jim antennas versus J-Pole antennas

Some Notes on the Slim Jim Antenna by Dave Coomber M0UXB

Slim Jim Antenna projects by N9TAX

Diamond Antenna CP22E VHF base station antenna review. This antenna has a remarkable design achieving 5 dBi directivity in a slim low-profile design.

Slim Jim Antennas are great for apartments and hotels. VHF UHF Antennas

If you like building good antennas, this one is for you. The J-pole is a slim, omnidirectional, half-wave antenna fed at the end through a quarter-wave shorted transmission line. Its predecessor is the famous Zepp antenna developed for the Zeppelin airship.

Easy to use online Slim Jim antenna calculator. Input your frequency to automatically calculate the lengths of the different antenna parts.

A simple slim jim antenna for 433 MHz. Simple drawings and pictures of a simple Slim Jim antenna.

The Slim-Jim is a bit of a classic - building one is almost certainly a rite of passage and you will be glad that you did: It is easy to make, fairly easy to tune and rolls-up for transportation.

A comparison among a traditional J-Pole Antenna and 2BCX Slim Jim Antenna

The Slim Jim VHF antenna, originally designed by G2BCX, is a folded half-wave dipole fed by a quarter-wave matching section. This version, built from a recycled professional aluminum dipole, demonstrates that various materials—such as copper, brass, or twin-lead—can be used. The article details the antenna’s construction, required materials, and tuning process, emphasizing mechanical stability and ease of assembly. With proper adjustment of the feed point, it provides excellent SWR across the band. Its durability and simplicity make it a practical and efficient VHF antenna solution.

The 4m Slim Jim antenna project provides a construction guide for a low-cost, high-performance aerial designed specifically for the 70 MHz FM band. This design achieves a 1:1 SWR across the 4m FM band with straightforward adjustment of the feed point, utilizing RG-58 coax. Its low angle of radiation contributes to effective signal propagation. Construction involves using plastic knitting needles as spreaders and a telescopic fishing pole for support, with components secured using two-part epoxy. Annealed bare single-core copper wire forms the radiating element. The setup process includes raising the antenna at least 3 meters above ground for tuning, adjusting the RG-58 feed point for optimal SWR, and then soldering connections. Waterproofing is achieved with yacht varnish. The design emphasizes low wind resistance for durability, making it suitable for exposed outdoor installations. A PDF construction diagram is available to supplement the written instructions.