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[phillnjack2]

Hello very new to 2.4 gig stuff so I will ask a few daft questions to those who probably know about this stuff.

I run large fast ic powerboats all over the place, rivers sea lakes infact anywhere that's wet enough to run them.

Now recently I have got hold of what I think is an amazing little 4 channel tranny and rx with 4 channels very cheap BUT
not heard much about this brand at all.
the make is ART -TECH  E-FLY 2.4 GHZ DSM 4 channel transmitter with an e-fly er62 6ch rx.
I have seen a few on you tube but mainlky by people promoting the stuff so they would obviously say its great and best stuff around, Yeah right !!!

Firstly I thought the Ariel wire on the receiver had been cut off as its only about an inch long, turns out this is the correct length ??????
this I think is a bit weird and might be a problem for the type of waters I run in as often I can even see the boats due to waves and wash
from full size powerboats on the sea for a split second or two, but at 50mph a second can be a long way !!!.
so what do I do about an Ariel (antenna if your a yank), as in where is best place to mount the receiver as ive heard some people say it needs to be up as high as possible and definitely above water line ??
can I extend the Ariel or do I need to mount the receiver up and out of the radio box, completely defeating the waterproof box its normally housed in ?

and what sort of distance can this set give on water ?
on land ive tried it and have not had any problems over a 1/8th of a mile but this was direct line of sight ?

any advice on this type of stuff would be good.



phill

[malcolmfrary]

As you look at the various threads on 2.4GHz you will find lots of mentions of aerial length.  Most radios work with an aerial length tuned roughly to a harmonic of the wavelength of the frequency used, this to minimize the length.  With 2.4, the wavelength is one and a bit inches, so that is what it needs and gets.  Some receivers, typically for park flyers, have the aerial internal to the case, some have it just poking out of the case, some have a longer aerial wire, but only the end inch is aerial.  The rest is a shielded lead-in.  Some advertise a longer aerial lead as a spare or optional extra.  Some have two aerials to improve reliability, which can increase range as a side effect
I hadn't heard of Art-tech before now, so have no specific knowledge of their products.  If looking for 2.4GHz for use at long range in rough water, I would be looking to mount the aerial, or aerials, as high as possible, even if it meant having the receiver up there with it.
Doing a search for this set only resulted in google picking up on everything but art-tech, so I didn't get any info that way.  Beware of indoor/park flyer radios - they are intended for short range only.

[w3bby]

IMHO large, fast petrol boats deserve more than a cheap radio....
2,4 is line of sight as all radios but with the added problem that it does not penetrate water very well. Loss of control is almost a given in some of the situations you describe.
The better class of radios have a detachable antenna on the receiver that can be replaced with a longer one, allowing mounting in the radio box whilst getting the tip (the actual antenna) higher up.
Some of the cheaper 2,4 radios are more of the "park flyer" type and may struggle with longer range.
Me, I use a Futaba FASST 3PM 2,4, the antenna is replaced with the longer item and it works flawlessly.

[phillnjack2]

the radio is one of those under all sorts of names, radio link, and all sorts.

I see what your  saying about the ariel and will do what I can about that

apart from the length of the ariel, (and I am very suspect about losing sight of the boat), the radio seems to operate fine.

suppose I will just have to get the reciver up high and mock up a radar or lifeboat canister to put it in  then just extend the servo wires.

[cos918]

hello
I is your boat so your call. Me cheep 2.4ghz for slow scale models . for fast models Top brands only


john

[malcolmfrary]

When a boat with a stood up 27 or 40 aerial gets in a trough, a few inches of the sight of the aerial might well be lost, with some reduction in signal, possibly not enough to stop it working, but these have an aerial between 18" and 2 feet long.  Losing a few inches on an aerial thats only 1 inch long in the first place means it's out of sight for however long, and will probably need a few seconds to recover itself when (if) it does reappear.  Old school might be the better answer.  There was a guy doing bait boats for use in surf (!!?) who used, if I remember, 40MHz, possibly for that reason.