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Discussion Starter · #1 ·
hey guys,


this is for my HoBao Hyper7 Nitro buggy abnd i am running 27mhz radio/reciever


when i have my engine off the servos/radio operates perfect.


then when i turn on my engine, and especially when i rev the engine, the reception cuts in and out. I have been running the same controller and crystals for about 3 months prior, without any problems.


when i hook it up to a fail safe, my fail safe cuts in and out. indicating to me that somewhere it is loosing reception.


anyone else had this problem? what could be the cause of it.


p.s its not interference from other people, coz there was no one else around.


thanks for any advice
Edited by: KyoshoKev
 

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Xtals are very delicate chips of quartz crystal... occasionally they can fail due to vibration or heavy impact. Try another pair of xtals.


The RX on a nitro car should always be wrapped in foam and tied onto the car. It shouldn't be servo-taped onto a solid part.


RX in nitros should also be waterproofed by sticking it inside a balloon or special splashproof rubber cover. Spilling nitro fuel onto the RX can often kill it.
 

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Have you changed any thing recently?

Do you have any metal on metal moving parts?...eg. Touch your engine block with a screwdriver with your radio gear on...it should trip your fail safe...is that the same thing you are experiencing? If so look around at what could be touching... and try to eliminate it. I hope this helps.
 

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Knox used to be bad for 27MHz gear due to all the truckies and their boosted CB transmissions on the highway nearby...
 

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AFAIK, only two things can cause the fail safe to cut in, interference
or low or interrrupted rx pack voltage. With interference, try another
location, borrow a friend's crystal's and see if there is any
difference.



If everything's fine without the engine running then rx voltage *level*
is OK, so I figure we might be looking at interruption. This also may
be indicated by the trouble manifesting itself when the engine starts -
ie vibration. I bet a bit of wiring somewhere is on the verge of
letting go, and the vibes of the engine are causing it to constantly
make or break contact. Or something is contacting a metal component
under vibration.



Check the wiring from the rx pack - wobble it around a bit. Check
*super* carefully all the wiring and contacts. The prob could be
located inside the actual rx in which case you may have to spring for a
new one.



Mike
 

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one of my mates recently went through 2 rx packs due to a similar issue. ended up being2x faulty rx packs. luckily they were under warantee and he had them replaced. he has digital servos which would chatter a little when firs turned on, then be fine, but once the engine would start it would just chatter all over the place before finally locking the steering over to one side. luckily it wasnt the throttle being locked on full!!!!!!!!!


if possible, borrow an rx from somewhere and test it with that, see if the problem persists. it may be a faulty rx....
 

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Discussion Starter · #9 ·
hey fellas,


thanks for all your advice


i have change the following trying to solve this problem


1. the 27mhz reciever


2. the remote


3. the tx and rx crystals. i changed over, it seem to work good for a few hours then it stuffed up again. i have some more RX/TX on order


4. batteries are full charged





I have since been told that it may be my engine bearings. I don't know how they work but he said it could cause metal to metal contact


this from madman also may help me heaps


Have you changed any thing recently? Do you have any metal on metal moving parts?...eg. Touch your engine block with a screwdriver with your radio gear on...it should trip your fail safe...is that the same thing you are experiencing? If so look around at what could be touching... and try to eliminate it. I hope this helps

my cooling head fins in the center have broken off and is dangling freely and vibrating like mad. this came around the same time that i had this problem. i had 1 fin break, then 2, then 3 LOL







i will try cable tieing the fins together to see if this helps. i got another cooling head on order aswell.


thanks for all ure usefull hints.


i let u know how it goes


thanks


kev
 

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ya a rattling disc of metal can cause RF... same with loose screws & partsetc.


Bung it up with some dabs of muffler putty!
 

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ha... its all Physics.



Radio Frequency waves are part of the Electromagnetic Spectrum.


So is light and sound - just differing in frequency/wavelength.
 
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