Tag Archives: antenna frame

How Much Radio Range Do We Need Anyway??

How far away can we see race marks, start line situations and sail numbers? Not far.

I’ve just had a bit of a shock though. You may remember that I have a horizontal, dead straight, line-of-sight, transmitter range test based in the street where I live.

I recently put Radiomaster and Futaba through the exact same test and basically got a radio range of around 200 metres for both of them. Blimey.

Radiomaster just a tad more maybe, but I ran out of straight street and had to go round the corner. That is way more than we need in radio sailing.. I can hardly walk THAT far.

You can read my recent range comparison for Radiomaster and Futaba here:-

Tests conducted by RC Flyers in the USA suggested that Spektrum only reached maybe a quarter to half the distance of Radiomaster/ELRS. I was curious to test my DX8e against it. I am just starting to prepare the Datchet Radio Sailors’ online manual for Spektrum. I thought I’d put my own lovely Spektrum DX8/AR620 through the same range test, using the same boat…. before I start the programming and manual writing.

I’m a bit stunned. At first, I thought it must be low battery power, and so changed all the batteries for fresh ones. Same result. So my next thought,… after swearing,… was “faulty transmitter”…. (you might say!!) …. but I’ve had this particular DX8 range tested and a fix applied at the Spektrum UK distributor, and it passed their tests just fine after that.

You might be thinking that it was caused by the smart but tiny, and wire free, ceramic antenna of the AR620 receiver. Maybe. Lovely kit though.

But the Radiomaster in this test also used a ceramic antenna in its ERC3i – even more weeny and more tiny that is. It’s so small, you’d be inclined to try and wipe it off the hull in case it’s a speck of mud.

The AR620 is about twice the physical size of the ER3Ci. When I get the time, I’ll re-test the Futabas without the SailsEtc antenna frame … just dangling wires in the pot … to be disproved, but I personally suspect the antenna frame (called “aerial holder” at SailsEtc’s website) is a big factor in this test.

I’m reluctant to trot down to TJD Models and buy a wire-antenna Spektrum receiver, as I’ve seen an official Spektrum video claiming that the ceramic antenna has better range.

But – well, how much do we need in radio sailing? I’d personally have difficulty racing 75 metres away – it’s surprising how far that is. I know a number of radio sailors who simply adore their Spektrums… but for myself, I’m still surprised by this test result. The guys at Datchet want me to test a FlySky over the same street. I’ll do that as soon as it’s practical – I no longer have a FlySky here, but I know where to get a loaner.

The article showing the results of the USA flyers can be found here:-

“Antenna Frame” Anyone??

When I read up about my transmitter’s working range, of course it’s all about airplanes and drones. “1.5km range”, I think it said.

Honestly, if the boat is further away than about 150m, frankly we’re on the limits of my eyesight! I’m sure most folks would pay no attention to the layout of the onboard antenna (two wires that stick out of the onboard receiver). I’d forgive anybody who thought it doesn’t really matter. I did notice though that when we initially rigged my new IOM at the Datchet club, the first thing PH told me to do was walk a really long way away and see if I could waggle the sails via the mainsheet joystick. The “voice of experience”, I suddenly thought to myself.

Did you know, the theory is that the two antenna wires should lie at right angles to each other?? The IOM I had been borrowing from a totally amazing man at Chipstead had this simple idea.

Aboard my new K2, the builder has integrated something into his proprietary pot that ties the antenna at right angles. Very neat actually, … job done.

For the F6 Marblehead, GH suggested looking at two potential antenna frames on the Sailsetc website. We chose this one….

You might miss it at first glance. The frame is that little black moulding at the top of the photo. The two “arms” at right-angles are hollow – you can thread the wires inside them easily. It weighs about the same as a sheet of Kleenex. I’d guess its is 3D printed. Very neat. It simply sits inside the pot and grips the edge. It is shaped for the standard 60mm Sailsetc “pot” that the majority of us have. You thread the antenna wires through the 90 degree “V”… then what? I just wound my antenna tails around the pot rather than thread them back over the frame. It keeps it jolly tidy in there, plus at least some of the wires’ length lies at 90 degrees.

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