Baud rate and frequency

[Spectacular Butter]

baud rate

Does anybody know how to count the frequency from the baud rate?

In the Visual Basic program, i selected 9.6k for my baud rate for transmission. I wanted to know how to get the modulating frequency from the baud rate. Thanks.

 

[Nigel Goodwin]

baud rate

Does anybody know how to count the frequency from the baud rate?

In the Visual Basic program, i selected 9.6k for my baud rate for transmission. I wanted to know how to get the modulating frequency from the baud rate. Thanks.

I don't really understand what you mean by 'modulating frequency'?.

But, 9600 is the number of bits per second, there are usually ten bits per byte (1 start, 8 data, and 1 stop) - although this can vary, depending how you wish to set it, but this gives 960 characters per second. So if you divide 1/9600 you get 104uS per bit, and this is the time delay between successive bits - and the value you use to write software RS232 at 9600 baud.

 

[Spectacular Butter]

oh thanks. This signal from the RS232 is suppose to add with my carrier signal. Just wanted to know the frequency of this signal because i need to add in a low pass filter at the receiver end to remove the carrier and retain the signal from the rs232.

 

[Nigel Goodwin]

oh thanks. This signal from the RS232 is suppose to add with my carrier signal. Just wanted to know the frequency of this signal because i need to add in a low pass filter at the receiver end to remove the carrier and retain the signal from the rs232.

This sounds horribly like you don't know the first thing about radio in general, and even less about data transfer over radio links :cry:

 

[Roff]

oh thanks. This signal from the RS232 is suppose to add with my carrier signal. Just wanted to know the frequency of this signal because i need to add in a low pass filter at the receiver end to remove the carrier and retain the signal from the rs232.

This sounds horribly like you don't know the first thing about radio in general, and even less about data transfer over radio links :cry:

I agree with Nigel. You have a lot to learn, but you gotta start somewhere.
In the transmitter, the data doesn't get added to the carrier, it must modulate it. The carrier frequency is determined in the transmitter. You can't simply remove it with a lowpass filter in the receiver - the job of the receiver is to demodulate the signal to extract the data from the carrier. A lowpass filter after the demodulator is still required to remove the carrier and/or its harmonics.

 

[panic mode]

did you try to find suitable modem? i don't know if you are limited with
space (if this is supposed to be portable) but there are units like from conexant for embeded market...