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Author Topic: which is best rf module to interface with atmega32 ?  (Read 1135 times)

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Offline RAAJ90Topic starter

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which is best rf module to interface with atmega32 ?
« on: August 14, 2011, 03:42:40 AM »
i am making wireless robotic arm

which is best rf module to interface with atmega32 ??
my range is abt 20 feet.Tx433 has lot of noise interferance so cant use that?which is best but still in my budget of $15 ?

Offline Soeren

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Re: which is best rf module to interface with atmega32 ?
« Reply #1 on: August 14, 2011, 06:52:46 AM »
Hi,

my range is abt 20 feet.Tx433 has lot of noise interferance so cant use that?

Did you try it out?
Most (if not all) of the cheap TX/RX modules will, in lack of a proper signal, raise the input sensitivity to a point where the noise comes out at normal output level.
As soon as a legit signal is received, the AGC lowers the sensitivity to match the signal strength of that and the noise is no longer an issue.

I use these modules and deal with the noise issues by preceding the actual coded message with first a short pulse (~5ms or more depending on purpose) and then a short pause to tell the receiver to listen. This is very easy to detect as a start signal for the attached controller.

The AGC in the modules I use will stay at the reduced sensitivity/gain for around 40ms to 100ms (depending on the length of the previous pulse) and then it's back to the noise consisting of short random width pulses. The proper signal has got much wider pulses than the noise.
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
Please remember...
Engineering is based on numbers - not adjectives

 


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