2,4GHz and carbon

[me6kius]

Hello,
Now I am using Futaba T7CP, but i had a lot of disturbances an my boat, so I decided to buy Graupner MX-12 or Spektrum DX7. But I have one question: will spektrum system work when the hull of boat is made of carbon? Hatch of boat is made only of glass fibre, but all hull of carbon. So will it work fine? Has anyone tested it?

[LtDoc]

me6kius,
I have no idea why your boat and the 'T7CP' has problems. I suspect it's because of the carbon fiber acting as a shield to the required signals. If that is so, then the 'Spektrum' radio systems will probably have the same problems. It's about like trying to receive any signal with the antenna and receiver sealed inside of a 'tin can', not much signal (if any) ever gets inside. The simplest 'cure' is to get the receiver's antenna(s) out of that 'tin can'/carbon fiber environment. How you would go about that is up to you, and isn't going to be very simple or pleasing, all things considered.
It's certainly 'do-able' though!
Good luck.
- 'Doc

(to some ridiculous point, 'ugly' is better)

[me6kius]

I think that problems could be comming from the motor. It is brushed Team Orion motor. I have lead receiver antena out of hull in all my boats, but I have problems only with that one that has brushed motor.
P.s. Also I heared that new Futaba's (that are made in China) are big piece of s**t... Besides Spektrum has a lot of advantages against 40MHz radios.

[CG Bob]

I think that problems could be comming from the motor. It is brushed Team Orion motor.
Are there capacitors on the motor? The brushes can cause arcing and sparking as the commutator shaft spins, these arcs and sparks can cause radio interference. Installing capacitors on the motors eliminates the "motor noise (http://www.loyalhannadockyard.com/Motor%20Noise%20Suppression.htm)".

[Hoghappy]

A lot of the new motors already have the caps and a lot of the new radios are a lot less susceptible to the interference to start with...I know the Spektrums are good ones...then there are the lemons! :p

[John Pilot]

I would do both:

1. Put capacitors on the motors (although with a 2.4 GHz system, that type of interference should not be a big deal) - between the terminals and between each terminal and the can

AND

2. Get the antenna out of the hull

Although I do think item 2 will get you a bigger improvement.

Just my ¢2

[AndyKunz]

A long time ago we had a problem with the carbon hull where the motor was not grounded to the hull. All kinds of fun! If there is some way to tie the motor can to the hull itself, you may find that helps.

Also, make sure there isn't any way any metallic part of the radio system (rx, sx, antenna) touches the hull.

Andy

[me6kius]

It is possible that antenna touches carbon in the hull. I will try to fix it. But anyway I want to have 2,4ghz radio. Will it work when the bottom side of hull is made of carbon and top side is made of glass fibre? Or maybe it is possible to lead 2,4ghz receivers antena out of the hull like it is done with 40MHz?

[ghostofpf1]

It is possible that antenna touches carbon in the hull. I will try to fix it. But anyway I want to have 2,4ghz radio. Will it work when the bottom side of hull is made of carbon and top side is made of glass fibre? Or maybe it is possible to lead 2,4ghz receivers antena out of the hull like it is done with 40MHz?
There are long standing discussions in the glider forums about CF and 2.4G compatibility and it seems if you can get your antenna out of the CF shadow you'll likely be OK.
Meaning don't let the CF get between your rx and tx at any expected orientation and all should work well.
Hope this helps
Ghost

[me6kius]

Ok. I found new radio, that I think I will buy. It is Airtronics Sanwa MX-3G. What do you think about it?

[expat flyer]

The Sanwa like the Spektrum DX3 or DX3R is likely to suffer the same as all the Spektrum surface radios that don't work too well near water. For improving the reception there is a description of mounting a remote antenna on

http://www.anderswallin.net/2005/10/spektrum-receiver-antenna-modification/

or for extending the antenna on

http://www.users.bigpond.com/rmgsw/Misc/SpektrumRXExtension.htm

However it would be different or impossible for the dual receiver air radios (DX7, DX6, DX5E).
For those the best solution is to get the receiver antennae above the carbon for sure, and above water as much as possible. Not too difficult to arrange given the small size, light weight and immunity to interference.

[me6kius]

I have tested Sanwa mx3 radio in the shop: we turned on transmitter and receiver and then turned off transmitter. Both servos stand up in position that they were in the begining, so the fail safe really works.
My friend uses Nomadio React radio in GP boat and it works fine, but I have only electric boats, and they dive or turn over quite a lot. But I hope it will work fine.