Whip aerials
 

I'm going to try a whip aerial as after putting two servos in the tail of my latest plane my range has decreased drastically. Down to 35 paces :( With the aerial outside I got 45 paces, which I still think is marginal so I'm going this route.

Anyone tried these? I know Patrick Drack of Switzerland uses them but I've not seen many others. Any dos and don’ts? Any recommendations as to which are the best etc etc and where else I can buy them?

I was thinking of these ones: http://www.alshobbiesstore.com/cgi-b...%23a1633#a1633

Any info much appreciated.

Angus

RE: Whip aerials
 

Angus, you link doesn't work for others. Let me know how it goes, though. I went with dual elevator servos in the stab last year and had some range scares when I was wandering around the 200m range.

RE: Whip aerials
 

Hiya Angus, hope you 'northerners' are having more luck with the weather than we are down in London!!

Anyway, heres another couple of whip aerials available in the UK, also ile probably see Ali in the week ile ask him his opinion on the whips. I know ive seen em on his jets.

http://www.modelhelicopters.co.uk/ac...RadioAccs.html

RE: Whip aerials
 

Thanks Jason, will be making enquiries tomorrow. ps blazing hot sunshine up here ;)

Adam, I couldn't believe how much the wires shortened my range. Got the same setup on Synergy with no probs at all so I don't know why its affected the Astral so much. Wire length is about 1.2m (still need to shorten wire at servo end so it's coiled inside my tail for the mo). I am also going to put a ferrite ring on each of the long wires at the servo end see if that improves matters along with funky whip aerial.

Angus

RE: Whip aerials
 

I'm using the JR 1m extension. I have the short ferrite extensions, but I didn't try it.

RE: Whip aerials
 

I've had 15+ models with long moment arms with elevator tail servos and the only time I thought I had a range prob. it turned out to be a dodgy rudd. servo.
(not saying that yours is not a range prob. though)
Have you tried relocating the aerial wire, along the wing for example?

RE: Whip aerials
 

Hi Gus,

As you know I've used servos in the tail in every recent model except the Angel's Shadow and never a problem. Just a thought, have you tried a different Tx? I was just remembering how you had one modded by Mike Ridley to improve output. Any chance the higher output has overheated the output stage and is now causing a reduction in output?

Cheers

Malc

RE: Whip aerials
 

Well, I'd say thats very unlikely as range has remained great with Synergy and with Astral in its previous layout. For the tx to go at exactly the same time I mod the elevators I'd say is unlikely, but admittedly possible. Would of been interesting to try a different tx but there was only one 10x out with us.

As I said in the first post, with the aerial outside I only got an extra ten paces, not surprising really as the aerial is still close to the wires. I didn't try it along the wing. When u start doing that you may as well just go the whole hog and get a whip aerial. Basically I think the wires are too long (which can be shortened) + ferrite rings would prob help. Wires are actually about 1.4m I worked out. Synergy is less than a meter which may explain the difference.

Angus

ps All set for the first comp Malc?

RE: Whip aerials
 

Angus. I had similar problems when I put the servos in the tail of my Eclipse. I thought using long elevator cables wasn’t a problem with modern receivers but apparently it can be. I’m using a Graupner SMC19DS and with the elevator servo cables connected the range was reduced by approx 60%. I found out that adding a couple of ferrite rings eliminated the problem entirely (but added some annoying grams).

David

RE: Whip aerials
 

Hi David,

I'm now getting twisted servo wires instead of the "normal" ones as well. Then I think ferrite rings won't be required. Ordered a 12 inch whip aerial today :)

Will post pics of set up once done.

Angus

ps you going to Switzerland?

RE: Whip aerials
 

Whip aerial probably solves it, but it gives the model such a toyish look :D You know “Nikko style”

I’m not sure about Switzerland yet. I'd hate to miss it, but it may have to be that way [:o]

RE: Whip aerials
 

Hi Gus,

I'm interested to see if twisted extensions work but to be honest I doubt they will. I have been speaking to Ben Werner of Mutimode Technologies who make a small filter unit which connects between the ESC and the receiver in electric models to stop noise entering the RX via the ESC.

I have asked Ben whether his filter might do the same for long servo leads and he is optimistic that it will. As you will be using a separate receiver battery and don't need a BEC connection through the filter unit you can use the LC version which only weighs 2.2 grams. I assume you have two sets of leads from separate channels in the Rx so you will need a filter in each lead.

You can contact them here and the good bit is that if it doesn't cure the problem you can return the unit for full credit.

http://www.multimodetech.com/index.p...tpage&Itemid=1

Hope this helps when you get fed up with a daft whip aerial sticking in your eye!

Cheers

Malc

RE: Whip aerials
 

David/Malcolm,

An Astral with whip aerial could never be called a toy. The Astral is so cool it's sub zero + my new whip antenna looks mighty fine as well + will take aerial right out of the way of wires etc. This has to be a better way of doing it.

Yes those noise filters look good Malcolm, but at $21 a pop I think I'll try the twisted wires + whip aerial first before I spend any more money.

Who knows, once I've got the plane sorted I may actually be able to do some practice.

G

RE: Whip aerials
 

I will be curious to hear your result. It just came to my mind that any aircraft I’ve seen with these whip aerials have been either electric or turbine, but never ic. I wonder how they will handle the vibrations in a pattern airplane. Maybe the antenna will do some funny tricks when throttling. Fatigue maybe is an issue

David

RE: Whip aerials
 

[quoteI will be curious to hear your result. Same here --maybe a one off---But we had a guy in the local club who had to have everything.
His latest heli had a whip aerial(reason unknown).
When we range tested the remains the range was into single figures (measured in feet).

RE: Whip aerials
 

I've run servos in the stab on just about all my planes and never had range/interference problems. I use Futaba. On my big planes I do use twisted wiring that runs from the servos all the way to the receivers - again, never had any problems with that setup either.

As an experiment - try replacing one servo at a time to see if that clears up your problem. I mean ALL servos, not just the stab servos. If that doesn't work, then replace the RX (if you haven't done so already) and then lastly, try replacing the switch and battery pack. One change at a time and you may end up solving the issue.

-Derek

RE: Whip aerials
 

http://www.gbrcaa.org/documents/comp...ages/chip1.jpg

Ignore Chip Hyde growling in the foreground. Check out Patrick Drack's YS 140DZ powered Smaragd in the background :)

I very much doubt the whip antenna setup would have fatigue issues, it's a very well made piece of kit. Hopefully be trying it all this weekend.

RE: Whip aerials
 

Normal wires + internal aerial = Range 35 paces
Normal wires + external aerial up to the fin = 45 paces
Normal wires + whip antenna = >180 paces

Have not tried twisted wires yet.

RE: Whip aerials
 

Have you tried replacing those servos of yours that are in the tail? With the external antenna running outside the fuse going to the rudder you should get the same amount of range as the whip antenna. I suspect some major interference coming from those servos in the tail that are affecting the antenna running to the rudder because of the close proximity.