Little Devil Antenna

Thanks, my main requirement is to provide additional mobile phone coverage when travelling outside if the CBD.

My backup is a 9505a Sat phone.

It will be mounted on my bullbar of my Hilux. To make things "worse" I have an iPhone and the only way I can get an external antenna is via a passive antenna coupler on the phone holder.

http://www.ebay.com.au/itm/130886263587

I like the idea of the Little Devil because of the size, easy to get in/out of car parks. My Hilux is also my main daily commute vehicle.

I travel in areas where mobile phone and TV are difficult to dodgy. I get other campers asking all the time how I have TV and what is that white aerial I have up.
The have dodgy TV aerials like the Saturn Omni, Happy Wanderer which do not have sufficient surface area/metal to receive sufficient signal like a phased array or yagi. They get sold these small dodgy expensive TV aerials and told they will get reception everywhere. If they worked everywhere they wouldn't make large TV aerials like the phased array and yagi. Even if you have a TV aerial amplifier you need the signal to amplify. To receive the weak signal you need the metal and surface area.
Same with phone and internet reception. They say they have an aerial and you find they have a little aerial for their phone 30cm or a multiband small broom stick aerial. The multiband phone aerials cannot give the high gain reception of a dedicated long dipole (whip) aerial. The ZCG MA915 is a dedicated 850Mhz Telstra Next G aerial and will give you the maximum chance of signal reception. That is the reason I use that aerial and is the phone aerial of choice of majority of the RV fraternity. Reason it works.

A person giving praise for an aerial in one location has nothing to compare it with or know the signal strength. A small receiving area cannot receive the signal strength of a large surface area.

Sadly there are no miracles in aerials of any type. Surface area, size and length will always be king. If you could make a small aerial and make massive claims these type of aerials would be on the market from large professional companies.

I don't recall the maker of the Little Devil claiming miracles Andrew but he does say his aerial doesn't need a groundplane to work. Someone with a physics degree might know if this is reasonable, I certainly don't.

Although the sample is small a few on here over the years have given positive feedback on their LDs. But I take your point in regard to the technology and its uptake, with the obvious rider that the fact that many people use 'X' can have as much to do with advertising (doubt if many people even know of the LD), availability, cost, and pack mentality as it does capability. Must admit it crossed my mind that if his antenna was as good as it sounded it probably should be very well known 4+ years on. Perhaps the technology has improved so that the advantage he had years ago has been diminished?

The antenna doesn’t impress at all. There is no technical data just frequency range. The tin shed workshop doesn’t look like a professional enterprise. I think if you seriously wanted to sell the antenna you’d pick a more appropriate place to film like an office or laboratory of some sort. The magnet seems to stick to the aluminium van sheeting and the eaves of a house, setting up the kid with the antenna in such close proximity to metal structure inside that small tower is not the work of anyone who knows antennas, neither is the work van with ladder racks and ladders which would very much shield that small antenna if on the roof looked like they would overshadow it and if the tower was behind you not a clear path for the signal at all .. zilch, he claims it works everywhere! Early in the presentation he claims the radiation pattern is low, then later on in relation to the boat rocking claims it has a high radiation pattern so counteracts a boat rocking … what nonsense. Seems very much like an amateur out to make his fortune. The antenna may work ok but I very much doubt over that bandwidth it would have much gain. It looks like it is constructed in poly pipe with end-caps. Doesn’t look very professional to me at all.

"Firstly...remember mobile phones run right up at the border between UHF and microwave" Telstra NextG is 850Mhz which is the only system worth talking about.

"...this absolute distance restriction is intentional and necessary for network function." is incorrect with NextG WCDMA. GSM had a restriction on distance. Telstra has NextG towers up to 200km range.

"you may also find that a bigger heavier aerial may not infact produce more gain than a lighter smaller aeral." Would like to see that.

"There may be some improvements in mobil phone reception achieveble.......but remember it is a system that is very intentionally and rigidly range limited." There are substantial improvements in mobile phone reception with suitable aerials. The MA915 dipole will give you 100km in good terrain and on the 200km range towers a Yagi aerial. NextG WCDMA is NOT range limited.

last time I looked, above 1GHz was considered EHF or microwave...NextG running right up in the 850s, is getting close to the border line between UHF and microwave...appart from the fact that NextG is not the only system arround, and people do use the other networks..and they most definitely are located above 1GHz.


While i may have been mislead or misunderstood the issue of time bassed absolute range limitation.....the primary limitation with mobile phones, because they work at such short wavelengths is the propogation being "line of sight" and that meaning exactly what it says.

regardless of how much power (and the system is limited to 25 watts in the base ststions and 0.6 watts in the hand helds) or how much gain in the antenna.....you would have to have a very high and clear location, INdeed, to achieve 200Km range.

As far as the various areials.

While there are 9dbi gain mobile antennas and 12dbi base station areials out there commonly, many of the big white sticks and big black sticks out there are in the 5 and 7 dbi range.

there are many wire and light fiberglass whips out there that produce 5dbi and some that produce 7dbi, fairly commonly available.

even some of the commercially available shark fin type antennas will produce 5dbi.

All the above figures are on the NextG band.

Choose well and the light weight wire or fiberglass whip may well indeed produce more gain than one of the lower gain big white or big black sticks.

If that light weight aerial is mounted high and clear where the big white stick is mounted on the bullbar...some 1 meter lower....the light weight antenna may very well handily spank the big white stick for performance....even when the Big white stich has a couple of points more gain.


Back to the original posters issue.......the little devil antenna shown in the utube advertisment is a can antenna...nothing new......what makes me scheptical is that they do not quote a gain figure for this antenna on their web site..so who knows how much gain it produces.

Interestingly, they also sell a big black stick, that they refeer to as "high performance"....and quote a 5dbi gain figure on it.

There are other low profile antennas in the form of shark fins, cans and stubs that produce in the line of 2 to 5 dbi gian.

As for NextG, not being range limited.....yeh right....anybody out there getting a consistent 100Km out of the NextG vehicle mounted or hand held mobile phone.???

cheers

Ok if you want to be nit picky....the traditional defiition of microwave is above 3 gig.


it does not change the practicalities and the line of sight propogation.

cheers

Bantam "As for NextG, not being range limited.....yeh right....anybody out there getting a consistent 100Km out of the NextG vehicle mounted or hand held mobile phone.???" 100km range is not an issue. Firstly you need to be on one of the 200km range towers and the rest is a breeze.
Currently we are 163km from the Telstra tower connected to a ZCG Yagi with a Netgear 761S Telstra modem making this post. Could unplug the modem and plug in the ZTE T82 Telstra Dave phone and make phone calls.

Bantam you obviously have zero experience with well made dedicated 850Mhz equipment or needing to have phone reception at that range. We have one system working daily at 202km on a dual Yagi.

We don't use toy aerials off eBay or made in back yard sheds with no specifications that make wildly false claims. We use professional aerials made in Australia by ZCG dedicated to 820Mhz to 850Mhz for the Telstra network. We don't play around with poorly made multi-band frequency aerials. Our first 700Mhz Telstra systems are due to come on line September for testing and expecting up to 250km range. The 700Mhz modems are on sale now from Telstra.

Yeh I thaught not.....there is a great deal of difference running a permanetly installed beam or array antenna probably on a mast or tower situation and running a hand held phone or a phone connected to an antenna fitted to a vehicle.

AND...that is operating with a special case long range mobile phone transponder.

AND nobody is talking about a yet to exist phone system running on the old band 5 television frequencies.

That is not what most of our readers are interested in...certainly not the OP

What is being discussed here is people running ordinary every day phones in vehicles.

For most of us we will be looking at more like 30Km range most of the time.....and the limitation most of the time will be line of sight.

AND as mentioned, one of the biggest obsticles to improving performance is getting the signal into the phone, because most of the modern phones that people want to use have no external antenna socket.

BTW the OP was considering an antenna from one of the most respected australian suppliers.....no mention of ebay.

cheers

Bantam 30km is nothing for a mobile setup. My 162km is on my motorhome. Heaps of RV's manage 120km with no issue.

LOL why do you think Telstra is currently starting selling the 700Mhz modems. Telstra don't start marketing equipment for fun. Telstra are a lot smarter than that. Aerial manufacturers are starting to supply 700Mhz antenna.

"AND...that is operating with a special case long range mobile phone transponder" there are 84 of these 850Mhz WCDMA NextG towers. They are nothiing special, Telstra place these long range towers where they have the altitude to get the advantage of the long range towers.
With the new black spot program announced by Malcolm Turnbull there will be more of these long range towers and predominantly on 700Mhz with Telstra. No idea what the toy boys in the mobile phone market are doing.