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Stubby aerials

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roycv:
Hi all, I bought a Fleet 40 Mhz RC set, 4 ch., with a stubby aerial.  This was in 1998 and I thought it would be a safety feature with the aerial being a foot long and flexible.

It took me quite a while to work out that  the stubby aerial had a range of about 50 feet at most.

 I bought a standard aerial, fitted it  and restored the usual expected range, out of sight, well its my glasses really!

Does anyone have a good experience with any other than the standard length aerials?

regards to all Roy

BobF:
Hi Roy,

I have a fellow club member who has one from the same era, and he has no problem with range.

Is the receiver aerial vertical or horizontal? I know a lot of modellers that route the aerial under the deck, but in my experience this is not good practice. Several of them have had problems with range including me, that went as soon as the aerial was vertical. Not suggesting that this is the problem in your case, but it is worth noting. Also unless the transmitter aerial is of the correct design length, this can cause problems and failure of output components. As with C B radios where the aerial was a separate item, a SWR meter had to be used to tune the aerial.

Hope some of the above may be of use to you.

Bob

Doc:
Roy,
You've opened a real 'can of worms' - lol, are you ready for this?
There are several 'standard' lengths for antennas, depending on who is defining the 'standards', which/what group or industry, and the specific use of the antenna/aerial.  A receiving antenna is one of those 'the longer the better' thingys  until you get to some ridiculous length (for the proposed place of use).  Receivers just aren't that particular as to what an antenna 'tastes' like, they get extremely 'hungry' so more-is-better.  Transmitters are different in that they have certain requirements in antenna/aerials.  Has to 'taste' just right!  If it doesn't 'taste' right, not much power is actually transmitted (a 'picky' eater!).  But!  The radio industry can change the 'taste' of things very easily, so shorter antennas can be used/eaten.  The problem is that while the antenna 'tastes' right, it isn't quite as 'filling' as the 'real thing'.  Meaning that the usable range for any shortened antenna/aerial is changed, that change being that it just doesn't go as far (sort of like Chinese food, you get hungry again very quickly).
If that isn't the most far fetched analogy you've ever heard, you need to quit hanging around 'those' kind'a people!
The simple fact is that 'shortened' antennas just won't have the same 'range' as 'full sized' antennas because of changes in their radiation pattern.  There's no direct, simple relation between range and 'shortness', it's complicated, and depends on each individual situation.  The 'standard' for the R/C industry isn't the same as for a 'communications' industry.  The maximum usable ranges for the two types are vastly different , as in do you really want a signal that can be 'heard' in another country?  I don't!
There.  If that doesn't have you completely confused, then I really am a genius!  Fat chance...
 - 'Doc

roycv:
Hi all thanks for your response.
Doc, hi,  I was an air radar fitter in the RAF some years ago now, and am conversant with aerial theory.  So when a manufacturer offers a stubby aerial I expect him to do his homework first.  I would expect there was compensation for the short physical aerial, centre winding or whatever to give an electrically correct length aerial.

I recall a comment from the owner of Fleet who said they were not as good as he had hoped!  I still have the aerial but I doubt whether I will use it again.  The actual equipment is excellent and in regular use.

BobF hi, I have 3 rx's as the Tx has a 8 model memory I switch between them. (currently in 2 boats with one going spare at the moment)
I agree with you about rx ae. position and my boats all have a fixed aerial usually up the mast and I have small gold plated plugs and sockets. These were component parts of 76 way computer cable connectors, retained from when I was a computer engineer.

The rx. aerial is cut down to a few inches and a gold plated connector is soldered on, this mates up with the connector of the fixed aerial in the boat and brings it back to the correct length.

I am interested though that you know someone who uses one.  I would be interested in knowing just how much range he does get.

Regards to all Roy

Mankster:
I have a 'stubby' aerial on my Robbe TX as well as the full lenght telescopic one. Range is down by about 40% but still fine for most of my purposes, and it is great for use indoors (geeting around doorways, boat in one hand in the radio in another, and less likely to poke your self in the eye). It is a helical aerial though, so max rang in achieved by pointing the aerial at the model rather than perpendicular to the model with the telescopic one to get the best range.

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