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Rx aerial length


Wraithstorm67

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No it cant.

The receiver wire is already at the correct length required.

Shortening it or extending it will affect its performance.[/quote

The wire won't extend out of shell I take it that's not a problem then just haven't tried the tx rx yet

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These days RC's run digital systems. 

 

in the old days we used analog signals, we needed to boost them with electronics and have a nice long floppy antenna wire.

27mhz (megahertz) mean we needed a long antenna. 

 

heres an anolgy. 

 

we have a pebble and a pond. we drop our pebble in and watch those concentric circles expand outwards.

now see the gap between each wave, thats our signal its about 3 inch wide, so at this wavelength

our best antenne to use would be say around 3 inch long or more.  now if our antenna was half the size

on the reciever its going to be tuned more for shorter waves more close together. so we may miss some of those bigger waves.

 

lets go digital, we now have a transmiter that kicks out signals in the ghz range (gigahertz) , our waves are much sorter and closer together,

so it means we do not need as big an antenna. take your 2.4ghz handset and its receiver, i bet if you was to measure the antenna length it would be NO MORE that

32mm in length , more closer to say 31mm. 

 

if you could see the radio waves coming from your antenna's they would look like a sugared ring doughnut , the center hole is your antenna ( where it would be)

and the doughnut dough is the antennas signal , its cast in a doghnut shape. NOW I BET you have all pointed your handset antenna at your machine, thinking it will help signal.

well if we think back to the doghnut we have some blind spots and one is the tip of the antenna. pointing at the car we LOOSE signal not gain. 

 

now 9-10 problems in the field are due to this natural though of pointing AT THE MACHINE. you need to train yourself not to aim at the car but think of you at the center of the doughnut shape signal

if your antenna is pointing horizontal - vertical and not at your machine, you have optimal coverage.

this same doughnut signal field eminates from your RX to  if you can stand that antenna up right vertical your going to produce the best signal doughnut

and leave the blind spots at the top. 

 

so not only do doughnuts taste good they kind of help you understand how your signal is cast and the shape the signal forms from your antenna.

you also notice if you point the handset at the car your signal has some blind spots. so remember upright antennas or at angles 

and sugar doughnuts shape.

 

when you get to far from range you can then work out the diamiter of your signal doughnut , some systems can cast to 1km , others a few hundred meters ( mainly the very cheap toy sets).

 

WARNING : Carbon fibre 

 

now your going to affect the signal here, carbon reflects the signal waves and blocks them so a full carbon chassis can cause problems

shadowing signal reception you MUST mount your RX as far away as possible from the fibre and/or use a carbon fibre use antenna.

 

If you ever break an RX antenna, around 31mm in length is what you require , this should be near on ideal you can tune by removing very small amounts

.02mm at a time and range test.

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