RC India

Requesting help from Experts on this topic. unable to find details on other threads.
I am unsure of placement of the TX antenna in my boat.Which one of the following methods is appropriate to get the maximum range .
I am installing a 35 Mhz Esky RX.
What will be the impact on the range and will there be glitches.
1) Can I place the antenna wire inside the periphery of the boat . Will this affect the range.
2) Should I place the wire in a nylon tube and install the tube vertically on the boat.
3) can I place the antenna wire inside the periphery of the boat and solder the loose end to a steel wire and install the steel wire vertically as an antenna on the boat.
Need Help.

Shreekant

Put a Nylon tube as a mast and loosely wrap the Rx antenna wire around the mast on the outside.
Check out the car guys placement. They have the same issues as a sailor.

i thought the wire is not to be coiled.Kindly correct if this is incorrect.

You are not supposed to coil the wire, wrap it loosely around the vertical mast (nylon tube) and leave the last few inches loose and hanging. As said earlier, see how heli and car guys do this and you would get the idea.

Look,

the wavelength of the 35MHz wave is 857.142cm (300000000/35000000 m) Now use one eighth length i. e. 107.142 cm height fron the water level whivh give you mirror effect and you get a quarter wave antena. If your mount is higher, make a vertual ground with reflector like microwave.

HAMAERO may give a more details. the attenuation is to b kept in mind.

107 cms??? That is approximately 3 and a half feet above the water level. Impractical. I've never seen an RC Boat with that kind of an antenna height (unless it happens to be a monster boat). Let's not get too theoretical about this. Do a range test on land and let her sail. All the best!

Yes, thats true. But that is the theory. Generally even numbers are divided to generate. If not possible, make again half or you may again half. Sometimes a smaller than that is also used (as the effective length is a little bit long which further depend on the diameter of the wire/pipe). But the length is from virtual ground plane for reflection of wave and maximum efficiency. But afterall, trial and error will get the final result (Stub Tuning perhaps). Generally just measure the lengths of the cheap 27MHz Cars and measure the range. Now just increase it's another half length and check the range. for range muasurement, keep the transmitter radiation at low by keeping antenna short.

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The key factor is the resonance.
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You surely got a new play in older Tx and Rxs.

This is not traceable in 2.4GHz systems.
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The receiver systems are DESIGNED to use the length of antenna supplied. Alterations to the length will only make things worse.

107 cm is surely too long to accommodate. What are your opinions on the placement of the antenna within the boat along the periphery of the boat. Will this adversely impact the range?

Rooster,
Put it along the periphery of the boat and do a range test on land, it should work! However there is another issue, what material is your boat? If it is metal or carbon putting it along the rim of the boat may worsen the problem.
Check this link, may be it would help you
 http://ghmyc.org/Boat_Antenna_Configurations.html

Here is my experience with small helis... when we were flying with 72Mhz radios, we were using full size receivers on these, and obviously these are not long enough to keep the entire length of the antenna stretched properly.  So we tried our best to make it go around from one landing skid to a little bit on the boom support and back into the antenna holder attached to the landing skid on the other side. 

While this is not perfect, this did avoid looping the antenna back on to itself with no gap in between.  This provided us with plenty of range, certainly enough to fly the heli far enough that it would not be seen properly !

I assume you can follow something similar on boats also.