RF Transmitter/Reciver

[Fredrick]

Ok thanx for the information.

I agree that Parallax is expensive but i need the LINX module on an PCB becouse i don´t have the things needed to make my on PCB´s.

[mackrackit]

Ok thanx for the information.

I agree that Parallax is expensive but i need the LINX module on an PCB becouse i don´t have the things needed to make my on PCB´s.

http://www.rentron.com/remote_control/TXLC-XXX-LR.htm

[Fredrick]

Yes i have lookt at Rentron but 2 transmitter and 2 recivers + 2 anntena coast $111 and at parallax $109,95 with antenna.

[mackrackit]

Yes i have lookt at Rentron but 2 transmitter and 2 recivers + 2 anntena coast $111 and at parallax $109,95 with antenna.

OK, but the antennas from parallax do not look very good (very short ), the ones from rentron are 1/4 wave.

As I said before, the antenna will make all the difference for long range.

Let us know how it goes.

[Fredrick]

Yes i will inform how it goes, and maybe i will come with some questions on the PBP program for the recivers and transmitter.

[Fredrick]

Are the Linx RF modules FM och AM?
Can´t find anything in the datasheet?

[mackrackit]

Neither, More like CM.
From the data sheet

When a logic ‘1’ is present on the DATA line and the PDN line is high, then the
Power Amplifier (PA) will be activated and the carrier frequency will be sent to
the antenna port. When a logic ‘0’ is present on the DATA line or the PDN line is
low, the PA is deactivated and the carrier is fully suppressed.

So, the only thing they can transmit is bits, think of Morse Code. ON OFF
That is why they work so well for serial communications.
Also, that is the reason for sending a "train" signal (010101010101) allows the receiver to balance the internal capacitor before receiving the real data.

I think the correct way of saying it is Carrier Present - Carrier Absent