Signal Strength Comparison Circuit - RF Cafe Forums
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Post subject: Signal Strength Comparison Circuit Posted: Fri Oct 28, 2005 6:06 am
Just wondering if anyone could help me with a problem:
Basically I am using two separate AM receiver modules and I want to display the strength of the received signals (using RSSI pin) however I only want the strongest signal of the two to be displayed. I intend to have a stepped L.E.D series for each of the modules to indicate signal strength, however i only want the LED series displaying the strongest signal to be active at any one time.
Does anyone have any ideas for creating this kind of signal strength comparison circuit?
Does anyone know of any similar circuits that I could modify or use as reference?
Post subject: Posted: Mon Oct 31, 2005 5:15 pm
Assuming your RSSI out of each module is a analog voltage, then all you need is a simple comparator IC (LM339, LM311, and many others). Run the two RSSI signals to the comparator inputs. The output of the comparator will be high is one is greator and low if the other is. You might use the output to blank one display or the other through whatever means you have available. You might need to add a little more analog logic for cases where neither one has a signal (i.e. blank both).