Anyone own a Midland MXTA26 antenna? What is your opinion of it? I’m thinking of replacing the antenna that came with the MXT400.
You don’t say why? But a 3db gain might be better for your circumstances.
I’m truly amazed manufacturers get away with crazy claims like these.
Specific Frequency: 462 MHz
Gain: 6dB (really? 6dB gain compared to what? )
5/8 wave antenna - (ah - now we’re getting there, a typical 5/8th wave vertical has gain over a ¼ wave. They’re often really 3/4Wave antennas, the usual short coil raises the electrical length to that of a ¾ so a 50Ohm match, but the physical length is ⅝ - gain wise
Everyone seems to argue over the gain so you probably get around 3dB over a quarter wave vertical because it’s NOT a dipole, and therefore doesn’t have the gain figure a dipole would have. You get of course a lower angle of radiation which is where it mainly comes from.
These crazy gain figures just play with the physics to produce a figure that has some science behind it, but applied in a very odd way. I always liked a 5/8th for two metres - it seemed to be clearly better than a ¼ wave whip.
32 inches in length
1.5 inch base diameter
In off road enviroments, trees, mounds, hills and mountains we want to talk to those near not far. The 3db gain puts out a better coverage for those at different elevations and thru the woods nearby. Remember “Line of sight” so say, you’re heading up hill and the others are over the crest, you may lose contact relatively quickly.
Looking forward to the report.
I suppose the thing that we all forget sometimes is that antennas are not magic. To get ‘gain’ there are only really two ways to achieve it. The bigger the antenna surface area, the more it captures. A quarter wave for 70cm is tiny, compared to a 2m one - so while electrically it’s identical in gain, the shorter length receives less! The other variable that appears to produce gain is for the antenna to direct it’s performance in certain directions. A design that has a lower angle of radiation appears to have better performance, unless you are in an aircraft up in the air and the antenna signal is hugging the ground. A Yagi concentrates it’s capture area in a narrow beam in front, so if it has 10dB of gain, it needs careful aiming. An ancient ham I knew years ago used a disused railway line fence - it was steel wire, on wooden fence posts and ran quite a long way. He matched it to use on top band and used to hear stuff nobody else could. Any antenna can be matched, but the reception polar diagrams in the vertical plane for a mobile can be very odd. The quarter wave with it’s donut shape wastes an awful lot of it’s output. 5/8ths seem to squash that donut quite a bit to get the gain.
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The gain does not increase power output. The gain is a concentration of the 40W your radio is transmitting. The “ghost” 3dB antenna that came with the radio will have a radiation pattern twice as high in the vertical, but won’t radiate as far as the 6dB antenna in the horizontal. In a simplistic explanation, the 6dB antenna will “squash” the signal “donut” out flatter than teh 3dB antenna giving a signal “pancake” of greater diameter (theoretically twice that of the “donut”). As someone said, the 3dB may work better if you are say, off-roading in hilly terrain. The 6dB antenna would be better suited for reaching out in flat terrain.
I think that’s what he was saying, to be fair. There is no increase in power, and that’s what the meter says comes out of the transmitter, what the antenna does with it is where the ‘effective’ bit comes from. Here in the UK and Europe we tend to use the transmitter power as the advertised figure, and not EIRP. OFCOM, our regulator are only interested in radiated power, so for comms licences, that is what they use, not transmitte power, which makes sense, because distance sets the reusing of frequencies.
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I did some portable antenna tests - and came to the conclusions that what was really happening was that so many were terrible antennas, and the popular ones were just OK, while none at all were actually practically good!
I put a simple marine band vertical on my office - really a dipole in a fibreglass tube, so gain over a dipole = 0dB, but it performs so much better than a handheld on the window sill just 8ft below. ANY antenna up in the air foes better than a handheld!
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It’s well known that most manufacturer claims about mass produced antenna products are somewhere between BS half truths and total ■■■■■■ sci-fi ludicrous.
The only ‘gain‘ figures worth a light, assuming they ain’t fiction, are gain relative to a half-wave dipole, since isotropic radiator relative gain figures (usually quoted as they look better) commonly used with vertical omnidirectional antennas are relative to a hypothetical radiator which would be dubious if it actual was built and laboratory tested.
So, a colinear’s gain relative to a vertically polarised half wave dipole antenna has some sound grounds to be credible. Likewise a corner reflector (as used as a compact high gain antenna on wifi or she usage) was genuine gain vs the dipole as do multi-element beams and co-phased or composite arrays of colinears vs a vertical dipole.
So working upwards, a 1/4 straight vertical is worse (even when optimally mounted) because it’s dB lossy vs a vertical dipole and more so as it’s emitted EM lobes spread the energy in many directions emanating from the driven element.
Optimally mounted, a half-wave dipole is unity gain (0 dB), so you ain’t going to see true passive gain until you move towards a colinear and then (optimally installed) you are into gain that’ll count for something. Similarly, focused directional antennas (parabolic, corner reflector and yagi beams) have gain advantage over a dipole in degrees of focused nodes that focus the EM nodes towards a narrower aperture of emissions.
How much difference a gain change, and bigger received signal makes or worsens very much depends on mode of transmission, especially on digital to critical degrees where SQ matters not absolute received Sig strength.
I’m getting up to 30 miles out of mind on a good day so far. It just sits there and vibrates, I didn’t know why and thought it was just happy to see me. Yea, I just don’t know how they work.
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momentarily get’s lost remembering when 30 miles was a distance contact on 30Mhz+
Well if it works and you get what you need, leave well alone and enjoy. Shame you can’t (legally) turn the output power way down and see how much you can get from almost no mW at the Tx, because you’d be shocked at what’s possible. That said, you could at least quasi-legally emulate it, highly inefficiently, with in-line attenuators on the antenna feed, but that’s a different chapter alone.
But it should be remember what xdB gain or loss really means as an end result.
Multiples of 3dB gain are progressively potentially going to increase your signal as received by S points (on old school non-RSSI SQ based metering).
So 6dB gain is really the lowest gain improvement worth having on the TX side. As far your Rx side goes, you’ll see some SNR improvement up to a point (but there’s a lot more to the effective SNR than how strong your incoming signal is). But remember that too much gain on the Rx side can actually worsen the SNR beyond the initial improvement and the selectively of the receiver can and will effectively worsen as the overly strong signal swamps the receiver. On a TX front, if you persist on using high power settings and a higher gain (higher than unity) combo unnecessarily, such as when working local stations, your inconsiderate misuse of higher ERP is actually worsening reception for others on the frequency who’s receivers are probably suffering degrees of being swamped.
That’s why, as a rule of thumb, only use what Tx power level in context to antenna gain to get a suitable ERP necessary to basically keep the communication established.
As anyone who’s been around using poor domestic, cheaper gencon and serious gen con receivers can tell you, in degrees within different modes, you don’t actually need to hear a big signal to get a an demod that’s intelligible and clear enough to resolve what’s sent.
Remember also, since some resort to active antennas to solve a ‘deafness’ in a receiver rather than use a moderately higher gain or more focused antenna, preamps have their own internal ‘noise’ which gets transplanted onto the output, which is why (in simplistic terms) you’ll never get a clean full x dB gain improvement at even the best performing frequency range, because the SNR you’ll encounter has been improved and subsequently compromises.
Passive gain is what you persue ideally, active gain (through linear amps/receive preamps and bilateral linear amps) is fallback. I say linear amps, because not all amps have any kind of decent linearity - and you definitely want linearity. If there’s no reference to define the amp as a linear, it definitely isn’t.
Ask anyone who’s measured the linearity and purity of any of those cheap power amps that used to (and probably still do) plague the CB market on 11m. The only good ones were the ones (the true linear not CB stuff trying to sell to the ham market) were the 10m specific stuff destined for hams and some were quite usable on 11m at the upper segment.
Ask yourself why if you look in radio stores and magazine ads and online why the ham gear linears are so pricey - markup aside, it’s literally paying for quality and purity.
The next best source we used in the ham world, and where legal in your particular licensed LMR use, were purpose built monoband linears on VHF and UHF built for LMR. Nowadays that may not be so absolute, but back then when VHF/UHF design was something of a black magic territory, you came to appreciate being able to repurposed LMR kit and sometimes it was the most accessible/affordable/or both entry point.
Note also, any antenna with loading coils (which synthetically compensate for poor resonance encountered by a physically short antenna) is efficiency down on a straight full electrical and physical length antenna. Likewise, where you have a coil, if you are stuck with a reduced size limitations, look for something with open windings.
A senior family member, also a ham, worked many stations across many counties mobile on 25W or less on a basic 1/4 wave boot/wing mount antenna that was barely more than the equiv of a straightened coat hanger (size and type of metal rod I mean, not literally) he simply put 3 or 4 (probably 3, my recollection is grey there) open coil turns and a calculated straight section. Given that same antenna was moved between multiple vehicles with the same effective inherent qualities over a period of 30 years+, it shows you don’t need a lot and half the fun was trying to run as QRP as possible and use the base rig for contests and extremes on a big yagi.
So unless you properly assess things, you’ll get poorer than you should get results, and if you go in blind, getting really good results is like getting a card game Full House or Straight Flush on an initial hand.
That should speak for itself.
Hmmm… I respectfully misunderstood your enquiry. I assumed you actually wanted someone else’s thoughts on the two antennas. It appears you already know everything and actually had no reason to ask the question you did, other than to troll the rest of us. My bad… (Just another Yankee, I guess. 
Thanks for your 30 mile experience‼️Apparently the Midland BS that some people allege isn’t such BS after all. I continue to be impressed with their products.
Thanks again😀
Well, to rock today’s perceptions a bit further and highlight a lot of misconception about one type of vertical over another, and use of loading coils for synthetic resonance -
Where the loading coil sits has as much to do with the effective range of a setup, and more so at VHF and upwards where ‘skip’ induced extra range only really occurs in a limited way due to low altitude pressure zones creating a tunnel rather than from high altitude charged layer reflections, as anything affecting the performance in direct EM Extended LOS.
And the type, and no. of quarter waves and half wave sections has a huge amount to do with firing angle and the size and number and patterns of emitted EM nodes that are the embodiment of your Tx’s RF out becoming ‘radio waves’.
But the real nuts and bolts and detail behind that would be a few volumes at least when you have to detail in reference to propagation to put meat on the explanatory bones, I’ll leave anyone who’s interested to go consult an older ARRL or RadCom handbook, like the pre-90s editions and save reinventing yet another wheel unnecessarily.
But in short, where 1/4 wave verticals are mandated, in any service, it’s an artificial engineered range limitation exercise at best - at worst, it’s in today’s terms, pretty wasteful and not very in line with the expectations of green ideals we’re supposed to be embracing.
I guess how I translated the soul of those antenna theory essentials did sound a bit last century radio handbook-ish, but they were good references many of us got our grounding from. As I said elsewhere, perceptions change, time passes, but unless we get a sudden realisation that physics as we know it just isn’t the case, then the physics behind propagation and antennas and feeders and transfer of energy remains true irrespective of what manufacturers claim.