i have doubts about infrared transmitter and receiver. hop someone can help me.
i did a lot of research on the net and found that most of the infrared trasmitter using 555 timer to generate a square pulse with high frequency. what is the purpose of the 'frequncy'?is it like the RF trasmission?or use to avoid the noise?if i direct connect the infrred LED in series with resistance, is it ok?
and at the receiver side, i saw that some people using PLL method to detect the signal.what is the purpose of PLL at the receicer side?used to eliminate the noise?
and anyone has better infrared tranceiver circuit that willing to share with me?i build a lot but none of them work fine
i did a lot of research on the net and found that most of the infrared trasmitter using 555 timer to generate a square pulse with high frequency. what is the purpose of the 'frequncy'?is it like the RF trasmission?or use to avoid the noise?if i direct connect the infrred LED in series with resistance, is it ok?
and at the receiver side, i saw that some people using PLL method to detect the signal.what is the purpose of PLL at the receicer side?used to eliminate the noise?
and anyone has better infrared tranceiver circuit that willing to share with me?i build a lot but none of them work fine