spectrum receiver distance issues

teambowen · #1 06-09-2010

Hi Guys.
I run a spectrum wheel radio and i have a couple of receivers that have issues at distance.

To try and resolve the issues i have replaced the aireal and cases on both units with no aparrent difference.

Both receivers are fully working but one stop's working totally at say 25 metres and the second throws a wobbly at the same distance.

I have tried them in both nitro and electrics cars, which makes no difference.

Can anyone tell me where or if i can send them off to get them checked as they're not cheap.

The rx's are sr3100 model abt £50 ish each.

It is almost as if the receiver signal amplifier is not recognising the tx signal strength is reducing and thus increase the amplifier gain.

Any idea's !!!!!

Jamie.

vladimir · #2 06-09-2010

Not sure how it is on your spectrum but my Acoms has got a fiture called Failsafe (to stop a car running away from you at long distance). So when the car is more then 25m away it blocks throttle only (servo keeps working for another 100m). so if your servo works fine at say 50 meters then most likely it will be an answer to your problem.

Benh · #3 07-09-2010

Quote:

Originally Posted by teambowen

Hi Guys.
I run a spectrum wheel radio and i have a couple of receivers that have issues at distance.

To try and resolve the issues i have replaced the aireal and cases on both units with no aparrent difference.

Both receivers are fully working but one stop's working totally at say 25 metres and the second throws a wobbly at the same distance.

I have tried them in both nitro and electrics cars, which makes no difference.

Can anyone tell me where or if i can send them off to get them checked as they're not cheap.

The rx's are sr3100 model abt £50 ish each.

It is almost as if the receiver signal amplifier is not recognising the tx signal strength is reducing and thus increase the amplifier gain.

Any idea's !!!!!

Jamie.

I once sent mine across a field (curiosity) worked fine until I could drive it no further, about 100meters. Might be worth checking/ replacing the aerial. May have been pinched/ knicked and your rx distance dramatically reduced.

The SR3500 less fussy, just tucked the aerial in amongst the other wires and it would just keep going. As soon as moved to the SR3100, that would need to go into a tube and hang out the top exactly as per instructions, or it would do as you described at about the same distance.

MatJohnson · #4 07-09-2010

Mine cuts out at about that distance, do we have any tracks which have 25m+ away from the rostrum?

Also, are you stood on the ground or raised up?

nitrokillah · #5 07-09-2010

I too thought that With All the new 2.4 ghtz I wouldn'd have anymore troubles .

though the glitches still appear from time to time .
both on my spektrum & my friends Sanwa ...

Mounting the Arial in a longer tube solved problem ...

hopefully that is all you'll need to do to get rid of your troubles ...

emtee · #6 07-09-2010

Have you checked the condition of the aerial on the hand set?

I have both dx2 'n dx3 set ups and have never had a problem with glitches or distance... My rx's are 3100's, some with a long aerial wire and some with a short aerial wire and all perform A1...

teambowen · #7 07-09-2010

Hi guys.
Thanks for the feedback.

point 1 new aerials on both receivers.
point 2 yes nitro tracks are future than 25m away. Even if they weren't it's still a risk to use them with people watching even with a double safety fence.
point3 one rx just stop totally, the second goes mad on both thro and string.
point4 No i must admit i didn't put the antenna in the aerial tube, i pushed it threw the front tower hole. But this should not have effected the signal as the car was pointing towards the radio during testing.

point5 the rx batteries is charged and are lipo saddle packs and also a 7.2v in my nitro.

I just thunk the rx's are playing up but i thought i would ask if anyone had come up with something to resolve the problem.

Jamie

burgie · #8 07-09-2010

Quote:

Originally Posted by teambowen

....
point4 No i must admit i didn't put the antenna in the aerial tube, i pushed it threw the front tower hole. But this should not have effected the signal as the car was pointing towards the radio during testing.

I really wouldn't have thought that because the aerial was pointing towards the radio would make a difference, afterall how would it know where to look?

Put your aerials in a tube and stand them upright, that is how they should be really, and then see what happens.

MatJohnson · #9 07-09-2010

Remember the transmiter outputs a wave signal, so, it needs an aerial standing verticle. If you expect it to go into the tip of the aerial then it won't, put it in a tube and it will help.

Also, the transmitter, make sure that the rubber aerial tip points upto the sky allowing the side to point at the car since the signal comes out of the sides more than the tip (i.e. if you point the aerial at the car end on, its not got as much chance of getting a signal).

Its the same theory as wireless networks, I'm just useless at explaining it.

Edit: Not the best diagram but might help. Red is the waves leaving the aerial, reverse for the car aerial:

And yes, it is the WORST image ever, but might help

Gnarly Old Dog · #10 07-09-2010

Jamie,
Get in contact with Horizon Hobby UK and speak to service / repairs.

I assume you can rule out the Tx being a problem - i.e. have you a 3rd or 4th Rx that works fine?

Anyhow, Speak to HHUK - they'll help you resolve your problems I'm sure.

emtee · #11 07-09-2010

Remove the top part of the TX antennae by unscrewing as normal... the hinge/unijoint stays on the handset BTW... and check the wire and metal/alloy parts are in good condition and in place where they should be... you can, I believe, split the handset and check the wire run inside the handset too...

markwilliamson2001 · #12 07-09-2010

Hi Jamie,

Was this at Ledbury, as i had the same issue when running my T4 truck there. This was with a plug in module in A KO wheel handset and I was running with the big grey opaque spektrum receivers. not sure if its the same thing, but the whole thing just used to cut out, and the truck would lose steering. It did used to glitch inside as well at leominster.

Since i have changed to a spektrum handset no problems...

See horizon, they are very helpful.

Big G · #13 07-09-2010

I know mine's a Futaba system, but I can drive mine to the point where I can't see the car anymore over the length of a football field (100m give or take) and still turn the car around and come back to me.

teambowen · #14 07-09-2010

HI Mark and Gareth and you other guyd for your advise.

As i have said i have 3 other rx's fitted in other car's/ rc8, B44 and x2 and the radio works fine.
So it's definately not the hand set.

I have been in touch with horizon and they have said to send them both back and they will check them out.
They were really really helpfull.

Mark, i remember you having trouble with you dx2 and you tried my hand set out to see if it was the receiver before sending the tranny back.

I will try the aerial upright test again but to be honest i bound them in my shed, 15ft by15ft like all the other rx's.
You could say it's like a faraday cage but it's not been a problem before.

Mark, are you going to be about Friday night mate.
It's been a while since you were racing in leominster.

I'll be trying out the lipos i bought from BIG G Friday.
All i need then is some foam boots and i'll be away lol.

markwilliamson2001 · #15 07-09-2010

Hi jamie, I think you think I am someone else, as I was racing two weeks ago! Ha Ha, will defo help ypu out though LOL

teambowen · #16 07-09-2010

Ah feck, it's chris you mean (from 2 weeks ago) reference photos.
Sorry dude, i thought you were mark from Ludlow who come over every once in a while.

See ya Friday lol.

Knupty

Matt Airbrushing · #17 07-09-2010

On my spectrum DX6i there is an option to do a range check where the power of the transmitter is reduced and you should still be able to control the receiver at a few meters distance.
Does the DX3 have the same option?

If your having problems with two receivers then the problem is likely the transmitter or the receiver installation.
In a car its best to have the receiver aerial pointing vertically. I have read on other forums that large metal objects (like helicopter engines) can block signals to receivers. For this reason some aircraft have satellite receivers that can be placed at multiple positions around the model.

It might be worth moving the receiver to a different position, or even temporarily taping it to the very top of the car to see if different positioning helps.

Horizons tech guys are very helpful if it does turn out that something is faulty.

MatJohnson · #18 09-09-2010

I've just tried mine, it does the same thing as yours.

Has anyone got an ideas on this?

How are you getting on with horrizon?

teambowen · #19 09-09-2010

To be honest i haven't sent them off yet as my road car is being worked on at the garage, but i intend to asap.
J

CW_ · #20 13-09-2010

I run a DX3s with 3300rx and I can drive it as far as I can see, had it in my nitro as well and no difference. The rx aeriel is only 4" long and works fine - I always have it upright in a tube though. If yours does not work at least 100 meters away its faulty.