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Basic RF transmitter question

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tarang

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basic rf transmitter

Hey guys,

I am using On Shine's RF transmitter and receiver (433Mhz) for my project. I was testing the devices other day but couldnt get anything at the "out" of the receiver.

I checked the antennea of the transmitter but the voltage is very very low and i dont think its transmitting properly.

Isnt it like if i send a pulse through transmitter the receiver "out" should give me back something similar? I am sending pulses through serial port using MAX232 chip. I can see the pulses on the oscilloscope at the input of the RF transmitter but i dont see any voltage at the antenna.

Can ayone help me with this?

Thanx
 

FvM

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rf basic

Do you have any equipment to see a 433 MHz RF carrier? You can use an oscilloscope with 500 MHz or above bandwidth, a demodulating probe (not very common) a spectrum analyzer or more basic RF instruments, e.g. a grid-dipper. Assuming the modules are basically operational, the receiver has a wide tuning range, it must be precisely tunded to the fixed transmitter frequency. Also the data rate is limited to 1200 or maximum 2400 baud.Finally the paper named specification is rather unspecific, you have difficulties to know even very simple things as the data input polarity.
 

Abhishekabs

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basic rf

Check the power of your transmitter on Spectrum Analyzer first.
Then see whether you have done impedance matching properly.
This will ensure that your transmitter is ok.
In the receiver side.
What is the bandwidth you are using?
You have to be very careful with sensitivity.
More the bandwidth less sensitivity.
Use filters to avoid interference & do proper impedance matching.
You will see the output.
 

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