align a PTP 820 link

The LINKPlanner installation report provides the Predicted Receive Power “while aligning”.

What does that mean?

When you’re trying to get two radios to talk to each other across the great chasm of life, make it easy on yourself.

Set the radios to the lowest fixed modulation mode possible, in this case, profile 0, QPSK.

Set the transmit power to the highest value allowed by the FCC—this is on your license.

Disable ATPC—Automatic Transmit Power Control. You want the radio to transmit at full power all the time.

Choosing the lowest modulation mode, setting the highest transmit power allowed, and disabling ATPC increase the likelihood that you’ll be able to connect the radios to each other.

Align the antennas.

Once you think you’ve got the best received signal level on each end (it should be the same as the LINKPlanner installation report’s Predicted Receive Power), then set your link the way it was designed.

This might entail changing your script to enable adaptive coding and modulation with a minimum and maximum modulation mode, or it might entail setting the modulation mode higher (but leaving it fixed.)

This might also entail enabling ATPC.

This might also mean changing the transmit power in accordance with the FCC license or LINKPlanner install report.

I hope this helps!

Dave

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