Surelink 900mHz

clayjay

I want to control the channel that I am using on a couple of Surelink 900mhz.· Is it possible to swith Pins 5 and 6 to low or high from a Basic pin so that you can control which channel the two cards are using?· I want to be able to relay a 'transaction' from one card to another so that I can increase the distance from the point of origination to the final contact point.· Any sample code would also help.· Thanking you in advance, Clayton Fowler

kb2hap

I am not am expert with these modules but I have used them before in some of my projects, with that said I don'see why it wouldn't work you would have to set up multiple transistors one that would be connected to + one that would connected to - and the other that would have to be NOT connected. I don't have any exact details yet... Just an Idea. (sourcing, sinking, NC). Basically your making a repeater. Would you need access to all the channels or just a few. If its just a few it my make the interface a little more simple.

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clayjay

Thanks for your reply, You are correct, I am making a repeater. Lets say I have 3 units, A, B, C. C reads the temperature and sends it to B, B then send it to C. If you have B listening on channel 1 and C listening on channel 2, then when A takes a reading and makes a connection to B via channel 1, B will then make a connection on channel 2 to C. I think you could put as many repeaters as you need to cover a short distance, 5 miles or less. Put a solar panel up and connect it to a battery and you should have viable relay system. To make things a little easier, if you made pin5 high or low, and pin6 high or low, you could have 4 channels. So do you think you could connect pin5 and pin6 from the Surelink board to a I/O pin from the Basic Stamp to shift the Surelink between high and low? CJF

kb2hap

In theory I don't see why it wouldn't work. I have 2 surelink units I will try to set it up in the next few days unless your already setting this project up. I'm not sure if you'd want to connect the stamp pins up directly you may want to try transistors in between. if you do try using the stamp pins directly which could work (hum?) make sure you use a little resistance in there. maybe a 220+ ohm in series between the stamp pin and the surelink pin as well as a 10k ohm in parallel to ground this way is the stamp is driving the pin the surelink will see a high and if the stamp is not driving the pin the surelink will be driven to ground.
anyways if you dont get a chance to try it I give it a try in the next few days. neat idea though

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