I take on board all you say and I will probably have a go at what you suggest. To be honest I hadn’t thought of using copper tube despite having loads in the shed.
However, and there’s always a however, I think you sort of missed the point. “Re: Three Easy DIY Antennas for Beginners”. ABCD567 will probably chime in here but I believe they are a starting point for we new people.
For me a lot of the fun is in the experimentation.
I started with a non functioning mag mount, which I fixed. I then moved it on to the windowsill and then out onto the roof (terrace). I was pleased with the results but I’m looking for range. Not really concerned with the league table as it would be hard to compete with those who live near busy airports like EGLL EHAM KORD etc. No, range is my aim.
Yes, a magpie, blackbird even a delinquent hoopoe might make off with the active part but hey-ho, it’s soon fixed. Saying that once the results are in I’ll probably try something different.
For me the important part is the 25 hits in the 180 to 240 range and the single over 240. They are all due to the new set up. Admittedly, not all due to the Cantenna. The extra 3 metres in height is allowing the antenna to “see” over the ridge at El Palomar and hence I can get traffic over Palma de Mallorca above 34000’
Thanks for your valuable suggestions. Definitely these will make the cantenna structurally stronger & durable.
There are two aspects involved:
(1) Electrical design
The Electrical design of Cantenna (as well as Spider) is very simple and has lot of dimensional tolerance. Therefore for a beginner & novice it is not only very easy to make it, but also very easy to get it right, and gives good performance.
Other more sophisticated and high gain antennas are also easy to make, but hard to get right, as these require high dimensional accuracy, both in design & in construction (many designs of collinears posted on internet are flawed). Example of these are coaxial collinear, wire collinear, franklin etc. These alluring antennas look very easy to make, but problem shows up only when these are put to trial run. In a novice DIY situation, only a few lucky ones get good results, and most end up with an antenna with poor performance.
(2) Material used to achieve the Electrical design
The whole idea of presenting the construction of Cantenna in the form proposed by me was to use readily available & low cost material to suite the “Beginners” as starting step. Definitely improvements are possible, and many did try these:
– A solderable bulkhead connector instead of insertable F-barrel connector.
– Thicker wire.
– Copper or brass tube (taking advantage of skin effect on high frequencies).
– Spray painting or applying enamel to reduce rusting.
– Enclosing the Cantenna inside a DVD case, or an inverted plastic jar or bottle. Please see:
Hi Phill
Congratulations. Your antenna installation & coverage looks great.
You will notice further improvement in range when you add an amplifier.
Regards
abcd
Yes, I’m pleased with it. And it’s hardly effected at all by the wind.
Apart from out towards Mallorca, I’m terrain limited, so an amplifier is only likely to extend the range that way. I’ll have a look on the fora for a good amp that is reasonably priced here in Europe. For preference I’d like to build my own which could add to the fun.
Whilst not doing anything for the range, do you think that it’s worth changing to the mutability version? I’m sure I read somewhere that you can display signal strength on aircraft.
@phillx19090:
Great coverage!
How much is the length of coax from antenna to dvb-t? What type of coax? (I use RG6 coax which is used with TV antennas & Satellite Dish. This coax is low priced and commonly available.)
It seems you are using Malcom Robson version of dump1090. If you use dump1090-mutability, it gives you many advantages, including range rings and signal level (dBFS) of each aircraft. Please visit page below to see how to install & configure dump1090-mutability.
Not so bad! No amp and using the magmount lead soldered on to the cantenna down lead. I couldn’t get the screen to solder so it’s just twisted.
I started my first dvb-t setup using mag mount whip placed near the Desktop to which dvb-t was plugged-in (due to short lead of magmount). Few days later during handling, the cable got pulled out from the mag-mount (no or poor soldering) . I lost my only antenna.
But this was a blessing in disguise. This prompted me to make a DIY antenna, and use 5 meter RG6 coax to connect, so that I could place my DIY antenna near a window which was about 5 meters from the Desktop. I used the disconnected magmount cable at dvb-t end. Since my soldering iron has burnt out at that time, I joined RG6 with the magmount cable by twisting, like you have done , and applied tape, so that the core & shield dont short. My first DIY antenna was a dipole with each limb 68mm (1/4 wavelength).
An unusually high level of traffic there. Perhaps there are a lot of “Hen parties” heading for Benidorm this weekend,
It’s thanks to you I’ve got this far. I’m not sure what the cable is, I grabbed an off cut from my local hardware store!! The cable is less than 4 metres long. Luckily I could get it into the ceiling space and then straight down to the desk.
Like you I had problems with the cable in the mag-mount. Shield not connected and hit and miss connection on the core. My iron gets fairly heavy use but I have to wear magnifiers to see what the hill I’m doing. I can manage smt, but only just and the tip of the iron seems huge.
Many thanks for the link to mutability. May be my eyesight, but I couldn’t find it until you linked to it. Linux, etc, is not my first language, but I’m getting there. Now if it had been in BASIC I might have stood a better chance. Since you’ve done the hard work and given a blow by blow account I’ll try and move across to it this weekend. Thanks for that.
Hi Phill!
The shield/braid of the most of the common TV coax cable can not be soldered as it is made of aluminum foil & aluminum wire. Twisting togather the two braids is the work-around for this situation.
However, some varities of TV coax do have copper braid, and these can be soldered.
Still working at mutability. When I look away from the screen I still see white writing!!!
Ali solders fine if you put a drop of oil on it and keep the tip immersed. Best way I know to solder wires on to lipos. For some reason it wouldn’t work on this braid. Maybe some other contaminant present. Hopefully the converter will be at the post office tomorrow.
Phill
[Edit]
Mutability working…sort of! It’s fine, I need to work out what I’m doing.
I have had 3 antennas from this seller and all work very well. In fact I have another one on order at present. Build quality is excellent and I have had delivery to both Aussie and UK.
Hi Andrew,
I just searched through my old emails and the antenna I had shipped to Australia was the 5/8 adsb and was priced at £20 (roughly $40) with shipping costing £6 ($12 ). I recall it taking around a month to arrive but arrive it did. I have just temp mounted the colinear I ordered the other day and have to say it is of nice construction and picking up more flights than the old antenna. You can calculate postage on his ebay site.
Just to add some information about one of the other professionally made antennas - I bought a Sandpiper ADS-B antenna used from ebay, which is the same design as sold under the Radar-Rama name. It’s quite well made, of metal construction with the N connector protected under the base of the antenna and inside the stub mast. The three radials screw into the hub and are nice and solid should a bird decide to land on it.
Performance wise It seems decent - results are quite similar to the franklin-spider that I was using previously, which was the best performing of the antennas I’ve made. It is currently mounted in the loft, which definitely inhibits performance somewhat and where it’s positioned in relation to structural members makes quite a big difference so it’s hard to directly compare. Maximum range is about the same or slightly better, and message rate is similar. I suspect that being inside is now the limiting factor rather than the antenna itself.
@caius:
A cheap indoor-type mag-mount copy of Sandpiper / Radar Rama.
With 1 meter RG174 cable & MCX-Male connector which fits into DVB-T dongle directly
$3.66 (£2.55) + shipping $1.01 (£0.70)
It is so cheap, I have ordered it, just out of curiosity to see if it really is as good as claimed (gain 2.5 dBi, SWR <= 1.5).
Expected delivery: when Chinese sail-ship anchors at west coast of Canada
The Radar-Rama was my first decent antenna that I purchased to replace the standard whip antenna that comes with the DVB-T dongle.
However, I used it for about a week, then sold it. Now I’m using my current non-metal collinear.
Why? Nice design, small in size etc. But putting a metal antenna way above the houses - making it the highest point. Changes it into a possible Lightning Conductor for a “Step-Leader” for lightning.
Just becareful when installing metal antenna’s outside, above roof tops. Especially if you frequently get Thunderstorms. As you wouldn’t want to return home after working all day, to find you’ve been hit by lightning
. I lost my only antenna.
, and applied tape, so that the core & shield dont short. My first DIY antenna was a dipole with each limb 68mm (1/4 wavelength).
