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[tonyH]

is it a really, really bad idea to enclose a 2.4G aerial, including the end bit, in a brass tube in order to disguise it?

[Martin (Admin)]

..... yes.

[Martin (Admin)]

A plastic tube painted to look like metal maybe be better ....

[tonyH]

Thanks Martin but it's one of those nasty bits that needs to be self supporting so I'd better try and drill out some 2mm carbon fibre

[John W E]

Hi tony
Carbon fibre and 2.4 g is a no go 
have a look here...


2.4ghz and carbon fiber? - RC Groups


john

[Colin Bishop]

Plastic tube is self supporting...

Colin

[tonyH]

Thanks John & Colin,On the PCS I'm finishing, the whole of the front half of the build is sealed and almost  the whole of the rear main deck lifts off so my plan was to have the aerial forming the aft "follow" light stanchion (Angled thing in pic) giving about 3 inches of elevation. Diameter of the stanchion would be about 2mm so drilling out the centre of 2mm plastic tube for the aerial is easily done but rather wobbly. CF would be strong enough as would brass/ali etc. but if they're no-go then I'll need to work on a Plan C  

[Ralph]

Evergreen do a 0.125" diameter styrene tube (works out to 3.2mm).  This would be self supporting and perhaps not too oversize to be noticeable.


Ralph

[JimG]

Only the very end , around 2.5 to 3cm needs to be exposed. The rest is a co-ax cable extension which can be in a metal or carbon tube without a problem. (The outer in the co-ax is earthed which shields the inner, only the exposed end can receive any signal)
Jim

[tonyH]

Thanks Jim, I can live with that and disguise accordingly. I had the feeling somewhere in the back of my mind that was the case but you know what it's like at the end of a build when you discover you've finally lost any brain-power you started with.
Thanks again to all.
Tony

[Akira]

2.4 ghz antenna does not have to be "exposed" as per say. as long as it is fairly well positioned above the waterline of the ship, it can remain  within the hull or superstructure of the model with no ill effects in relation to range and telemetry. your PCs sould haave plenty of space to put the antenna without having to disguise it as a stanchion.

[tonyH]

I've decided to compromise so one spur of the aerial runs along the underside of the deck while the other pokes out of the deck at the stern and up the follow/convoy lamp clamped on with a couple of rings of shrink tube. Just needs a bit of tidying up but should work fairly well.
Tony

[warspite]

pity it couldn't have been hidden inside the main tube or even disguised as one of the supports

[tonyH]

Agreed, but plastistrut wasn't strong enough and I tried drilling a 1mm hole through a 2mm graphite tube but it kept splitting so..........

[tonyH]

Couldn't think of a better title for the thread so here's another probably stupid question.WHERE DOES THE POWER TO THE SERVOS COME FROM?I'm using a non-BEC Action P81 very soft-start esc, so the Rx has its own 4.8v pack.Do I presume that this also powers the servos?The so-called receiver packs normally stop at AA size cells and this must limit the doable work. Is there any reason why I can't just make up a C/D pack or would it be better to change the esc for a BEC one and use the fact that the motor has 4x6v lead acid lumps acting as power source and ballast?The reason for the question is that I'm linking several mini servos and although they, in the main, only act once to release things, there are other larger ones such as the rudder one, which continue along with the ESC itself.Or, is there a better way?
Thanks
TonyH

[JimG]

TonyH, the AA cells will normally have enough capacity to power the receiver and servos for several hours. Modern AA cells have around 2500 to 3000 mAh capacity, when I started radio boats we used 500mAh capacity cells and sailed for at least 2 hours. There is no reason why you can't make up a receiver pack with larger cells, I have in the past used subC cells for this when a bit more weight would be useful, although even they were only around 1500 to 2000 mAh packs. Thye only problems with AA cells is if you want to use them to run a motor, they have higher internal resistance so can't source higher currents. However the receiver and servos don't take all that much of a current in use as they are normally at rest. The only time I would be concerned about the current used is if you were using digital servos, these use more power due to the way they work.

Jim

[Ralph]

The RX pack will power your servos (and anything else connected to the receiver).  I still use a number of "old school" pre BEC electronic speed controllers (anyone remember the Electronize kits?) so I have several 4.8v AA receiver packs in different models, including a sub with an esc and 6 servos.  I make a point of ensuring the RX batteries are fully charged before I go sailing and have never run out of power so far.  AA cells are available with quite high capacities now (I think mine are generally 2500mah) but if you feel you need more, there's no reason why you shouldn't use larger cells and make up your own packs (when I sailed model yachts I used 5 cell packs to give 6v for extra speed/torque on the sail winch).


Alternatively, and others will be able to give you better advice on this than I can, there may be suitable equipment around which would drop the voltage to allow you to power your RX from your drive batteries - effectively a separate stand alone BEC.


Ralph

[tonyH]

Thanks Gentlemen! This is about the first time I've used more than engine and steer so I'm a bit more than naive when it comes to "Sound, Lights, Action!", so hopefully all those servos, cams and micro-switches will spring into being assuming, of course, that I push the joystick in the right direction!