how to use two 433MHz Rf modules in same place using encoder decoder !

Hello guys ! I want to use two 433MHz rf transmitters at same place !
I have implemented 2 RF transmitter & receiver circuits using :-
-Easily available 433MHz modules from ebay.in
-Ht12d & Ht12e ICs for decoding & encoding data !
These encoder & decodera have facility to àdjust address also !

So i have configured different addresses to my 2 transmitter & receiver Pairs !


But even after setting different addresses these two RF systema doesn't work! (Both Work flawlessly with other transmitter turned off i.e. only one transmmitter ata time !)


Please help me to solve this issue! Z

Post circuit ans code. Don't expect help without doing it. Have you put antennas to all the 4 RF modules. If not put 18 cm wire as antenna.

With two transmitters on the same frequency transmitting simultaneously they will interfere with one another. Imagine two radio stations transmitting on the same frequency. You need to use different frequencies or only transmit in short bursts at random intervals, not continually.

Keith

Thanx keith , this means the only way is to use another frequency module ! Because in my application both transmitters should be able to work simultaneouly !



@ Jayanth , yes bro all rf modules are connected with 17cm antenna !
And both systems works absolutely fine when another is turned off ! So my circuit is not wrong , its a problem with module only !

How much data are you transmitting? It is quite possible for multiple transmitters to share one frequency but they must transmit in bursts.

Keith

^ ohhk Got it bro ! i am not transmitting a lot data ,,I am using HT12E encoder ic which has 4 inputs ! I am using only 2 of these ! Its just a Wireless switch ,,& not like wireless data Acquisition system !

Are you using these 433MHz ASK RF TX/RX pairs with a microcontroller?

If so have you considered replacing the ASK RF TX/RX pairs with an inexpensive transceiver with built-in encoding/decoding, like the Nordic nRF24L01+?

You can purchase a pair of nRF24L01+ transceiver modules on eBay for less S2.50 shipping included.

eBay Search for pair of nRF24L01+ modules

Nordic Semiconductor nRF24L01+ Product Page

nRF24L01+ Datasheet

They are fairly popular and straight forward to utilize in an application, as such there are C source libraries available for many microcontrollers.

BigDog

^ for using this,,i think i need to use controller on both sides ! transmitter as well as receiver !

Yes, which is why I asked whether or not you were using a microcontroller with the ASK RF TX/RX pairs.

BigDog

^ No i am using uC on receiver side only ! On transmitter side there is no uC !