The W3FF Portable Dipole

This is the antenna I designed for my 'walking portable' station.  It is a dipole constructed out of the plastic plumbing pipe CPVC.  There are telescoping whips at the ends of each side of the dipole, and these whips are adjusted to bring the antenna into resonance on each of five HF Bands.....10, 12, 15, 17, and 20 Meters. The longest elements are on 12 and 10 Meters, where the dipole is actually a full half wave.   On the lower three bands, coils are used to shorten the antenna. It takes just about a minute to make band changes. Operation on Six and Two Meters has been tried successfully too. It costs about $30 to build this multi-band, portable dipole.

Note that the coils are not tapped. They are taken out of the circuit entirely on 10 and 12 Meters.  I use one coil for 15 and 17 Meters, and a separate coil for 20 Meters. Details on the 2 and 6 Meter operation may be found later in this text.

For complete construction details visit the W3FF website: www.qsl.net/w3ff
 

The $4 Special Antenna  (by Joe Tyburczy, W1GFH)

Sure, you can find "all-band wire antennas" for sale in the back pages of Ham magazines costing $150 or more. But beware: Marconi spins in his grave every time a ham buys an aerial instead of building it. The plain and simple truth is that wire antennas for the HF bands were intended to be hand-made and not store-bought. 

Untold generations of intrepid Radio Hams have fashioned their own equipment out of spit and bailing wire. Do you think the spark-gap dudes of the 1920's just went out and bought ready-built G5RV's from HRO or AES? No way! They slapped together aerials out of bedsprings, chewing gum, and frozen cow poop. For them, every day was Field Day. I think that home-built antennas should be awarded 10 db of "honorary gain" simply by virtue of their ingenuity. And in this world of microprocessor controlled micro-rigs, constructing one may be your only chance to build something and actually see it work on the air. 

For complete construction details visit: www.hamuniverse.com/fourdollarspecialw1gfh.html
 

Remotely tuned, antennas have been around for decades. Military and others used them during WWII for HF radio communications. Normally, capacitors and inductors are tuned by electric motors with gear boxes to reduce shaft speed and provide the torque necessary to rotate the component. Both air and vacuum variable capacitors have been tuned by this method. More ingenious are variable inductors, ranging from edge-wound coils with rollers to pancake spirals with sliding shorting blocks between turns. Internal and external tuners in amateur HF transceivers use small DC motors to tune capacitors in a tee network. Tuning an antenna, either directly or conjugately, by a motorized tuner is a technology that has been around for a long time.

For complete details visit: www.antennex.com/preview/Folder01/screwdrv/screwdrv.htm
 

It's a dipole... It's a vertical... It fits in your travel bag! The Buddipole™ is more than an antenna, it's a versatile system for launching your signal. Optimized for transmit power and proven for DX work, the Buddipole™ is the secret weapon used by HF portable operators all around the world. Visit: www.buddipole.com
 
 
 

The Yaesu ATAS-25 is just the ticket for temporary FT-100D Field Operations. It covers these amateur bands: 7, 14, 21, 28, 50, 144 and 430 MHz. The bands are covered by manual changing the supplied elements and hand adjusting the coils. See the chart below. HF and 6 meter power capacity is: 100 watts SSB/CW 50% duty cycle and 50 watts AM/FM. Power capacity for 144/430 MHZ is 50 watts in all modes. Maximum height is 7.2 feet (2.2m) 2.05 lbs. (930g). An Allen wrench and three radial wires are supplied (20, 9.8 and 6.6 foot). It comes in a small box only 24 x 4 x 2 inches. 

This antenna requires a camera type tripod base (not supplied). The antenna has an SO-239 (PO) antenna connection, ready to accept a PL-259 plug. 50 ohms nominal. Matched SWR Less than 2.0:1. Please note that several items illustrated above, such as the radio, base, table, tent and coax are not supplied. The ATAS-25 is not designed for permanent, long-term outdoor operation. 

Visit: www.universal-radio.com/catalog/hamhf/40443473.html
 

Portable Antenna Systems

MFJ-1798 80/40/30/20/17/15/12/10/6/2 Meters Vertical Antenna:  get full size performance with no ground or radials!

MFJ-1621  Portable HF Antenna 40M thru 10M: Portable HF Antenna covering 40 Meters through 10 Meters

MFJ-1622 40/30/20/17/15/12/10/6/2 Meter Apartment Antenna: MFJ-1622 Apartment Antenna covers 40 through 2 Meters, mounts outdoor to windows, balconies, railings.

MFJ-1796 40/20/15/10/6/2 Meters Halfwave Vertical Antenna: Only 12 feet high and has a tiny 24 inch footprint! Mount anywhere -- ground level to tower top -- apartments, small lots, trailers. Perfect for vacations, field day, DXpedition, camping.
 

Equipment for portable HF operations  Selecting a portable HF antenna (II)

What antennas are today available on the place for portable operations ? By definition a portable station is a station located at another location that the base one but not set up as a fixed station (thus /P, not /A). Optionally this second station is subject to move from time to time, but not as regularly or as fast as a mobile one. This location has not only to be located a few km away from the QTH but can be a spot selected for the holidays, sometimes abroad and that you can also sometimes only reach by boat or by plane.

So that means than the antenna used for a portable operation must be light but it can be heavier that the one use in mobile, and even cumbersome in some cases. 

To read this excellent article on postable antenna systems visit: www.astrosurf.com/luxorion/qsl-portable2.htm
 

Let us look at the ground rod. 

A series of articles on developing an effective grounding system for your amateur radio station posted here.