Rf Transmitter

[Anniyan_x]

dear al, i hav built a RF TRANMITTER RECEIVER refering al using nigel pic tutorials. i built 2 units to controll different thngs. the problem is tht let say both remote controller TX is powered, it cant function...if either 1 is unpowered the other functions accordingly..im using RF module which has 3band...rite now both using the same band..is it mite the cause or wat?? whn both remote are powered,it doesnt function..the TX led lits up but no RX, i put both near,if one remote unpowered(battery removed) the other remote then funtions accordingly and vice versa. any help???

 

[3v0]

is it mite the cause or wat??

yes each RX TX pair must have its own frequency.

 

[Anniyan_x]

how abt if same band but different address...so only one should work at a time..then how abt the concept of car remote controlls...does al the car remote controlls use differents bands?? anyway il try to analysis again wat went wrong.

 

[Nigel Goodwin]

how abt if same band but different address...so only one should work at a time..then how abt the concept of car remote controlls...does al the car remote controlls use differents bands?? anyway il try to analysis again wat went wrong.

Car remotes use the same frequency, just different addresses - but only one transmits at a time.

 

[sajivjess]

Better use a Decoder & Encoder IC's such us HT12D & HT12E, so that you can select your own address

 

[Nigel Goodwin]

Better use a Decoder & Encoder IC's such us HT12D & HT12E, so that you can select your own address

Those IC's are simply preprogrammed micro-controllers, my tutorial programs do the same thing as them - but different addresses aren't enough, you still can't have more than one transmitting at the same time.

 

[Pommie]

I thought that part of the license for "license free" modules stipulated a maximum duty cycle of 10%. The pic should therefore only power the transmitter when needed, not all the time.

Mike.