Summary of RF antenna related calculators

A short list of RF antenna calculators. Basically created as a reminder and quick 'goto' for myself to quickly get antenna segment measurements when I need to create a new antenna. Something to note here is that these calculators are pure theory, in practice slight deviations are often required (hint: see 'Slim Jim' gap dimensions, the antenna length is correct, but cannot deal with the 'gap'. You have to deal with it in the upper and lower bends.). I use these antennas for Amateur Radio purposes, but also for GPRS, LORA, ADS-B, WiFi and more.

Note to self (and others): Always add a 'bit' more to the lengths of the antenna elements (EXCEPT for collinears [you must do this right first time. See the notes!]). It is easier to file off material than to add it! See the photographs of the Udo Yagi prototype where I botched up.

DMR Hotspot Booster Antenna

Boost the range of your DMR hotspot by replacing the supplied antenna with this antenna construct. Simple to construct, light weight to transport, out performs the standard antenna that is normally supplied with DMR hotspots.

ADSB antenna performance test

Antenna Calculator for a J-Pole Antenna

Easy to make compact antenna using less material than the Slim Jim antenna and very suited for mounting (hiding) in PVC pipes.

Antenna Calculator for a Slim Jim Antenna

Small area antenna, ideal for (hidden) placement in PVC pipes. Has better performance than the j-pole antenna. Looks like a folded dipole, but is not. More sensitive to finding the matching spot (good SWR) than the Slim Jim antenna.

Antenna Calculator for a Quarter Wave Antenna

A forgiving antenna regarding slightly off measurements. It uses the most real estate compared to other antenna types here, but is really easy to make. The thicker the antenna elements are the broader the bandwidth will be.

Antenna Calculator for a Coaxial Collinear Antenna

An antenna made using coax segments. The more segments added increases the gain of the antenna, however there is a limit to the benefit as you add segments. Uses a choke on the feedline as 'ground plane'.

Antenna Calculator for a Collinear Dipole

A collinear antenna with groundplane. This type of antenna has gain above the standard dipole antenna, making weak signals stronger and getting a larger reach.

Antenna Calculator for a Dual Bi-quad Antenna

A 160 degree (+/-) directional antenna with gain. Excellent for use with WiFi where you want full coverage in house, but not to the neighbors, or to beam across a long area.

Antenna Calculator for a 3 to 15 element Yagi directional antenna

A very directional antenna for 3 to 15 elements. The more elements you add, the more gain is achieved and the narrower the directional beam becomes. Of all the above antenna designs, this one was rather tricky, a load of research went into this one, variations from fixed element spacing to what almost looked like a log periodic were modeled looking at the volume of space required for the antenna in comparison to gain achieved, beam width and side lobe effects. As I use this design for telemetry tracking in aggressive RF environments, the more complex variable parasitic element spacing design was chosen. This is what this antenna design calculator is based on.

Short base loaded whip antenna calculator

An antenna type that is ideal where space (length) is limited. An antenna shorter than the frequency intended becomes capacitive, to compensate and maintain resonance, an inductor is needed. This calculator will calculate the inductance required for a short antenna for any sub GHz antenna.

The Aruba 'solderless' 1/4 wave antenna

When you are far from home, short of time, and need a solution to improve a requirement quickly. This is how the solderless Aruba 1/4 wave antenna was conceived. Not of requirement, but as concession. The result was not to bad at all.