Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Problem with RF receiver link

Status
Not open for further replies.

Abu Ammora

Full Member level 2
Joined
Jun 13, 2005
Messages
135
Helped
5
Reputation
10
Reaction score
2
Trophy points
1,298
Location
East Coast
Activity points
2,482
I tried to make RF Link , Freq. = 85 MHZ , Modulation is FSK, I build the TX , and the RX was simply A radio whose o/p is 100mW , All i did is disconnectiong the speaker and take the o/p directly to P16F84A Microcontroller and increase the volume tuner . and by monitering the edges of the square wave signals and the duration bet. them i can know if the tranmitted signal is one or zero , and displaying result on LCD ( 1 or 0 ) , i also made a modification that when TX is just opened and no data will be tranmitted TX will send a square wave signal ( i called it signal 2) which the RX will understand it as the TX is opened and NOTHING will be appeared on LCD

The problem is that (TX should be first ON before the RX is on), when TX is turned off , Strange 1's and 0's appeares on LCD as it's from the background noise of the radio , how can i get rid of this problem , i want as there's TX is closed , and RX is opened no o/p on LCD ?
Thanks

signal (0) duration = 555HZ
signal (1) duration = 1KHZ
signal (2) duration = 10 KHZ
 

PaulHolland

Advanced Member level 2
Joined
Jan 15, 2003
Messages
664
Helped
95
Reputation
190
Reaction score
34
Trophy points
1,308
Location
Holland
Activity points
4,841
Re: Problem with RF link

HI, Make a packet with CRC on your data and check the CRC before accepting the data as valid !.

Paul.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top