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mbw123
- 29th October 2006, 19:27
I am going to use the RX433 receiver from Qkits (http://store.qkits.com/moreinfo.cfm/RX433)
and I am unsure about the difference between the linear (pin 3) and digital (pin 2) output pins on it. For my project, I have a 16F628A sending serial data out that will be received by another PIC on the receiving end. What should I use?

Also does anything need to be connected to the other pin that I am not using?

Thanks.

-Mike

dhouston
- 29th October 2006, 21:26
The linear output is the input to the data slicer. Its amplitude will vary with signal strength.

The digital output is the output of the data slicer. It swings from rail to rail.

The data slicer is a comparator with the signal on one input and a capacitor that charges to an average of the input amplitude on the other input.

I use the digital output for data and use the linear output with an ADC pin as an RSSI (Received Signal Strength Indicator), measuring the difference in amplitude between a pulse and space. This makes it really easy to tune the receiver (if needed).

If you do not use the linear output, you do not need to connect anything to it.

You do need to keep the signal somewhat balanced between pulses and spaces as this balance affects the data slicer threshold.

You can see the differences on this webpage...http://www.davehouston.net/rf-noise.htm

Bruce Reynolds sells the same transmitter and receiver but under the manufacturer's (Wenshing) PNs. You can probably find some sample code on his site.