I stumbled across this article about HT antennas the other day while I was mulling the addition of a rat/tiger tail to my SOTA handheld. In it, the author uses an antenna chamber to measure and compare the stock antenna of a Yaesu FT1D with a reference dipole, a 1/4 wave whip, a 1/4 wave whip with a rat/tiger tail radia/counterpoise, and an MFJ-1714 1/2 wave antenna. There are a few surprises, not the least of which is that the 1/4 wave antenna on it’s own (no radial) actually performed worse than the stock FT1D antenna by about 9db. There are also some interesting measurements of the change in resonance when holding the HT, as well as how a radial interacts with the 1/2 wave and stock antennas.
Despite it being a somewhat limited study (N=1), it’s certainly food for thought and a good reminder that testing is essential for any antenna system. I’d recommend it to new operators and veteran mountain goats alike.
Good post and good article. I’ve always been a fan of the 1/2-wave 2m antenna for SOTA work. By design it does not require a ground plane or counterpoise, so it makes sense that it has superior performance.
The 1/4-wave result is a bit surprising at 9dB worse than the stock rubber duck. Of course, a 1/4-wave does need a ground plane or counterpoise…hence the improvement with the “tail” added. The author does note that holding the HT in your hand can improve the performance…you become the counterpoise (not well controlled). My experience is that the 1/4-wave works about as good as a stock duck, but consider that anecdotal evidence.
Without the benefit of an anechoic chamber, just comparing various antennas on an ICV85 HT, in an S2S situation at about 50km separation:
the separate half wave “flowerpot” style half wave is best - but it has the advantage of a bit more height than my 167 cm. Report is s9.
a telescopic antenna almost a quarter wave long is good. Report is s7
the original stock stubby helical is worst, report is s5
However tipping the HTs over to horizontal polarization at each location brings the stubby helical antenna up to s7ish, making up for some of the lost signal.
This change (to Horizontal) also brings up the signal on the quarter wave antenna relative to its vertical signal.
I think using horizontal polarisation for FM will blow some people’s minds because they have always used vertical. But grit your teeth and try it! (At both ends - cross polarisation is never better - but try that too!)
For antennas mounted directly to the HT, I’ve had very good reports on numerous summits using a Diamond RH770 telescopic (half-wave, radial-less, 93cm extended) even compared to a 5/8’s dipole on a 3m pole (and much quicker to deploy and stow away). The spec claims 3.0dB gain on 145MHz.
Before it fell apart, I also had a Chinese ‘770 clone [at about one-third cost of the Diamond] with a SMA-m connector that mated directly with the SMA-f on my Yaesu FT1D so was mechanically sound. The Diamond one seems to be available only with BNC and twice recently the SMA pin on two BNC-to-SMA adapters I used broke off mid-activation (presumably stressed by the antenna swaying about in high winds), now replaced by an adapter that sits snugly on the HT.
I’ve had good luck using a 2m J-pole made from 300 ohm twinlead cable (see example at The 2-Meter Roll-up J-pole Antenna ), yielding much better results than my dual-band Comet CH-72S, which is a quarter-wave on 2 meters. I’m cheating a bit in putting this into a thread on antennas attached “directly to the HT,” but this is almost so and is still portable. I have slightly less than a meter of coax feeding it. If there is no convenient tree branch from which to suspend the antenna, I can attach the top of the twinlead to the strap on my hiking pole, and then hold the pole up with one hand. The down side of this suspension system is that since the pole is aluminum, it interferes with the radiation pattern and makes it directional. For that reason it is necessary to experiment with position.Some time I intend to try one of our carbon fiber hiking poles and see what happens.
If in a hurry I use a 2m mobile half wave whip on my 817 with a BNC adapter, it works well but I wouldn’t try it on my handy without one of Richard’s helical filters!
I just recently did informal test with my rebuilt MFJ-801 field strength meter, and throw the results away by mistake. From memory, I used rubber duck as a base line.
RD with tail, some gain (about 1 line higher on scale)
Diamond ra77-ca about the same.
Diamond with tail another incredment higher.
Comet bnc-24, same results as Diamond.
MFJ 1/2 wave long ranger pegged the needle hard enough I could here it at 20 feet.
Plan to re-do it and also check out yagis as well.
Unfortunately, the Diamond website doesn’t say so it could be w.r.t. an isotropic radiator or a standard dipole
Since I started doing SOTA two years ago I’ve activated only about 45 summits (all in England or Scotland) and I’ve never had a breakthrough problem on 2m with my FT1D / RH770.
Perhaps, I’m just not visiting the right (wrong?) summits.
…or perhaps you’re not aware of the breakthrough. It can be hard to spot. I’ve had occasions where I only became aware there was a problem when a very local station called in to say “ there’s loads calling you - can’t you hear them?”
Many of the antenna manufacturers publish suspect gain specifications. Although Diamond makes good products, as noted they list this particular gain spec in “dB” which is meaningless. It should be either dBi or dBd. I see that Diamond often lists the gain in dBi (which is always dBd plus 2.1 dB).
For simple antenna configurations (such as a half-wave radiator), just look at the physical configuration. A half-wave is going to radiate like a half-wave dipole, which makes it 0 dBd or 2.1 dBi. Now there may be some variation due to how they match the antenna but typically this won’t matter much.
But, if my HT’s Rx was being desensitized by a seen or unseen comms mast, I wouldn’t be getting or giving all those previously-mentioned good to excellent signal reports using the RH770 with non-local chasers.
Good article. I got two antennas I added to my backpack for 2/440.
I got a ANLI AL-800 telescopic whip that adapts to my Knwd TH-D72A and it
works very well extended. I also got a 2/440 jpole rollup made by WB6IQN
after we viewed some of his videos at a local club meeting.
I tried both and they work very well. No specs on either one but I am satisfied
that for different locations they worked very well.
I will post when I activate another summit on their results.
My most ‘exotic’ home brew antenna to date is an 8 element coaxial colinear with copper microbore pipe stub - on a SOTABeam 10m ‘compact’ mast. Married with an FT-857 at 50w it worked quite well but I’ve not used it from enough summits to compare. Most of the time I use a Diamond RH-770, definitely 1-3 S-points above the. FT1XD stock antenna. How do you compare performance empirically when this setup got me from Stony Cove Pike in the Lake District to a mobile station on Norfolk?
