Tag Archives: antennas

Increase Your Radio Range by 50%… for £5.50 ….??

Fellow members GH and RU are always ribbing me in the bar that I should just chuck my Futaba antenna wires into the pot as a frame makes no difference!! G and R – this test result is for you!

For some time, I have used a 3D printed Antenna Frame from SailsEtc for £5.50. Do you all know what I am talking about??

This is the SailsEtc link

https://www.sailsetc2.com/index.php/aerial-arc.html

Here is my frame installed in a beautiful UK built F6 Marblehead. It is that little black arc you can see at the top of the pot. You might think that dangly wires on the receiver are “all aerial”…. but the lengths of aerial wire shrouded in grey that you can see in the photo are actually shielded. The lengths of wire that are unshielded and the actual “signal” bits, are the 5-6 cm end tips that are threaded into the frame at right angles. If you have Futaba receivers these tails have total length of around 8-10cm. If you have an RM ER6 the tails are 20cm long – but it’s still only the 5cm tips that pick up signal.

(©Datchet Radio Sailing)

First of all, I’d stress that although the measurements above are done in metres, it’s not an accurate measurement of ON THE RACE COURSE range. It’s better thought of as a comparative measure between technologies. At the Club there are definitely less signal obstructions around plus VERY importantly the control area is raised above the water by around 3-4 metres. Signal there should go further.

Instead think of this comparison as a %age comparison benchmark. If Radiomnaster ELRS is 100%, Futaba with antenna frame is around 98%, Futaba without antenna frame is about 67%, Spektrum is around 37%. All these signal ranges are perfectly good enough to go radio sailing. Honestly, the 200 metre benchmark would be impossible to race in, so you might say…”who cares?”.

So how did we get on?? Any conclusions??

1/ Adding the Antenna Frame increased my Futaba radio reception range by 50% on the test “course”

2/ Adding the frame put the Futaba in just about the same league as Radiomaster ELRS setup using a ceramic aerial. … further than you can reasonably see a radio controlled boat for racing purposes. I’d guess that a RM ER6 receiver would change the range-game again and be in another league altogether. NB uses one in his VISS.

3/ Most probably all these receiver components come from the same Chinese factory, so I’m still thinking that a FlySky setup would benefit by 50% with an antenna frame.

4/ If you have a Futaba in a SailboatRC boat, check the threading of the tails. Thankfully no carbon fibre to worry about, and the custom pot is fabulous with ready threading holes for the antenna. However, check where the tips are. If it ever stops raining, I’ll try the test with my K2/Futaba T6K.

These ranges are not as far as flyers claim for planes, but all ranges are much more than we need for sailing.

GH : bring you FlySky over in a carbon hull and we’ll check the range… with and without an antenna frame!!

Sail-away, Signal drop, Out of Range …. Have you considered that maybe it’s never the transmitter at fault?!!!!…

Last weekend was the third in a row where we have had a member’s boat drop radio signal while racing. First up was Hugh’s F6 – turned out to be battery, then my IOM – turned out to be the on-off switch, then last Sunday it was Jim’s turn in his F6. Not sure of the cause just yet….

It’s pretty natural when the transmitter loses the boat that our first reaction is to stare at the transmitter and growl loudly at it. The thing which you drive the boat with… using your highly skilled hands , just went dead on you, ….right there in your snug, and at a critical moment….. Natural reaction…. Grrrr

Have you considered it might NEVER be the transmitter’s fault?? These things after all are just solid state lumps of technology.

Phil has a great story of losing signal to the boat with a Futaba. Then he discovered that rotating the transmitter vertically, so that the aerial handle was vertical, caused the boat to reconnect and take off again. Interesting, but the weak link might still be at the boat end of things, ands not the transmitter in one’s hands.

Well probably not “NEVER”…. However, chat around our club members in the clubhouse and everyone has a horror story about every single transmitter brand, and it usually ends up “I had to throw my Spektrum/Futaba/Radiomaster/Flysky away….” (delete as appropriate)

So I came to thinking it might never be the solid state (not much variability) transmitter kit we all know and love. It might be the other end of the signal – the receiver in the boat that is the most common cause. We all spend a tad less care, money and attention on that.

There are a couple of very topical “antenna-less” receivers used at our club. First off is the Spektrum AR620 which is praised highly by Rohan and Craig (who gets five votes anyway!). No dangly wires causing variability according to way the way you chuck them in. The little built in antenna is designed by Texas Instruments. They say it gives better range than …. well, better than what? Better than their wired antennas, but we have no measure of them, do we??

Phil uses a similarly stunning wire-free ELRS antenna on his Radiomaster setup. Very strong performance I’d say. No drops yet. These wire-free antennas are about the size of a sugar cube, so it’s mind boggling that they can have better reception than lengths of antenna wire, but listen to the video above about the AR620

It seems to me that the key point is that they are going to have minimal variability from one outing to the next. VERY solid state. If it works well, it’s going to work well every time out.

By the way, next time you hear a “I had to throw it away” story, try and remember to ask if the boat hull was carbon fibre or fibreglass. Honestly – if you google “carbon fibre radio reception” you get simply hundreds of articles basically saying that carbon fibre near your antenna is never going to improve signal. It will quite probably weaken it – though not block it entirely. Would we know??…

I’ve a sailsetc type plastic pot for the receiver in my carbon F6 and I think I’ll do the same in the next F6.

So – we have wire-free good sounding receivers in Radiomaster and Spektrum. Futaba don’t sell one yet, and if you have a futaba you will be on dangly wire receivers.

If you are male and married, do you get this thing at home from the Steering Committee about women always read instructions and men never do?? … I know, I know…. me too.

This is the Futaba manual page about wiring their receiver antennae. I’d swear I knew all that, but when I just checked the F6…. well maybe I was not quite as thorough as I thought I’d been.

First up, we will all have fellow competitors who just bung the wires in the pot and get on with it. “Makes no difference”, (sounds like me) but actually maybe we never really sail much near the edge of range. I’m a bit like that, with a slight tendency to buy a gadget to cope with it – in my case a Sailsetc antenna frame – but as you will see, I still got it wrong.

The futaba manual is very clear that the antenna is mainly covered by a coaxial sheath ( I thought it was just a plastic sleeve). Only 1-2″ of bare antenna is exposed – and it’s those bare tails that are best fitted at 90degrees to each other. Both their examples in the manual also show that the antenna tips are ending up far apart. With the Sailsetc frame, you can thread the wires so that the tips come together, OR are far apart…. I confess, I thought the wire was in a protective sheath and just exposed at the ends. So I popped the whole sheathed antenna through the 90 degree Sailsetc frame….. WRONG, and NAUGHTY BOY!! The manual is very clear – only the exposed tails should be at 90 degrees.

You will also see that my antenna on a 3008SB receiver, first have a coaxial sheath, then have a rubber seal (not shown in the manual) and then only about 7mm of exposed wire. So I assume the rubberised length of about 50mm WILL receive signal.

I have rethreaded it and it now looks like this….

I’ll only know if it’s effective if nothing ever happens….