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[Martin (Admin)]

So getting back to my original question, what length is yours?....... 27Mhz aerial wire that is!  :angel:
.....Colin's 36" seems a bit long from memory!

[GARY C]

I have just measured the wire to my sons nitro buggy and total lenght is 480mm. His radio is Futaba 27mhz.

I have a funny feeling that the length of wire is not the same on other makes of radio,is the length of wire on a Futaba 27mhz set the same as Hitec, Acom, Sanwa 27mhz sets etc, or some of the Chinese copies?.
Prehaps a vist or phone call to your local model shop or give Howes a ring as they sell most makes, inc Chinese copies.

Dont forget it is not a critical length required.

Gary.

[malcolmfrary]

Mine (various Acomms and Hitec 27MHz) vary between a bit under 0.5 metre and a bit more than 0.75 metre.  Same results whatever.

[wideawake]

Mine (various Acomms and Hitec 27MHz) vary between a bit under 0.5 metre and a bit more than 0.75 metre.  Same results whatever.

That makes sense!   Given that the wavelength at 27MHz is near enough 11m then a difference of 0.25m is only about 3%.  A virtually negligible amount and well within the variation to be expected by different manufacturers' designs of aerial matching and receiver front ends.

By contrast, nipping 0.5cm off a 2.4GHz aerial of around 2.5cm is 20% - a very significant figure.

Cheers

Guy

[wideawake]

Mine (various Acomms and Hitec 27MHz) vary between a bit under 0.5 metre and a bit more than 0.75 metre.  Same results whatever.

That makes sense!   Given that the wavelength at 27MHz is near enough 11m then a difference of 0.25m is only about 3%.  A virtually negligible amount and well within the variation to be expected by different manufacturers' designs of aerial matching and receiver front ends.

By contrast, nipping 0.5cm off a 2.4GHz aerial of around 2.5cm is 20% - a very significant figure.

OOOPS I need to follow up my own post :(

The bit about 2.4GHz is true but not directly comparable with the 27MHz example.  What I should have said was that given that the wavelength of 2.4GHz is around 10cm, nipping just 0.5cm off causes a change of some 5%, nearly twice that in the case of the 27MHz case.

Guy

[Martin (Admin)]

I went to the lake today to test a boat... it was crap but I found a possible solution to the aerial length problem! .......
Doug99 will explain with a photo shortly! 

[dougal99]

Ooh Martin your so quick (or is it that you can surf from the office) 

Anyway here is Martin trying out his new Aerial solution.

Martin, It helps if you turn the RX on and don't try and sail with a clunk clunk cheapy, broadcast across the waveband, low power radio when there are 5 or 6 decent radios broacasting on specified frequencies nearby.

[osman123]

Just to complicate matters even further, I thought I'd ask a question on a similar matter but along the same vein. But firstly I best introduce myself as this is my first post within these forums.
My names Ade, I'm from the Bristol area and I'm near completing my first build (85%), a Precedent Huntsman 31 (48" Wooden Hull) which was bought for me as a birthday pressie back in the beginning of July. I've not introduced myself up until now as I've not really felt the need to as I have reasonable experience running Nitro Buggies & Trucks. However I have made regular use of these forums and have learned an awful lot of stuff I didn't know just by reading thru the threads as and when I've become stuck!
I'm a disabled person having suffered a serious injuries in a RTA 15 years ago and as such don't work and claim benefits, therefore everything I do has to done on a tight budget  >:( No 2.4 Ghz gear here I'm afraid, and even if I could afford it, gear like that would find it's way into the cars first That's if I didn't spend it on my first love of photography
Bearing this in mind, the Huntsman is temporarily being fitted out with 27MHz AM gear, purely because I can make use of existing gear I already have in the shed. I have found a whip Ariel and wondered whether fitting this might be a good idea and whether or not I'd need to shorten the the length of the receiver lead or just leave it at the length it is before soldering it to the whip???? Any ideas or opinions on this would be much appreciated before I go drilling holes into the roof of the boat!

Must admit to have been bitten by this model boat shenanigans though and have already started to plan my next build which I'm sure will either be a more complex model or possibly even a scratchbuild, so I'm sure I'll be making more use of these most helpful forums in the future.......

Regards.......Ade

[Don]

For those who want more information, some light reading (or more than most people want to know) try :  http://www.antenna-theory.com/ 

Ade - Try to keep the length of the antenna as it came from the manufacture; therefore shorten the length of the antenna by the length of the whip.

If you have what appears to be extra wire – don’t cut it – lay it out in long lengths in the hull.  For me, I usually tape it to the bottom of the deck.  Coiling up the extra wire can have an effect on it function.  The question is how much?  I’m never sure, and I don’t want to find out just as my boat goes out of reach. 

As much as possible try to keep it away from motors etc.  (not usually possible but….try).

Using the full length of both the transmitter and receiver antenna is optimal.
Having said that – it is not always practical.  Especially in small vehicles (cars etc.)

Don