At the PTP 820 BNC connector, the voltage range is 1.20 to 1.99 volts.
The last two digits of the voltage represent an estimate of the Received Signal Level (RSL): 1.XY volts corresponds to –XY dBm.
For example, 1.57 volts represents -57 dBm.
Notice that the lower the voltage, the better the signal level.
Don’t forget the following footnote from the PTP 820 Technical Description documents: “Note that the voltage measured at the BNC port is not accurate and must be used only as an aid.”
During antenna alignment, if at all possible, have at least two people at each end of the link: one person to adjust the antenna and read the voltmeter, and another person who’s logged into the PTP 820 radio to read the RSL values from the web page interface. (The web page interface RSL values are more accurate than the voltage measured at the BNC connector.)
If you have a voltmeter or multimeter that does not have a BNC interface but alligator clips instead you can attach them to an unterminated BNC cable. These can be found from many electrical component distributors.
Unlike PTP 800, PTP 820 does not have an alignment mode.
Log into the radio's web page during alignment.
During alignmnent, se t the radio a fixed modulation, lowest modulation mode, highest transmit power, ATPC off. (Be sure you have a link plan with these settings so that you know the expected received signal level.)
The person aligning the antenna uses a volt ohm meter connected to the BNC connector. They talks to the person at the base of the tower, who is logged into the web browser of the radio under alignment.
Once both ends are aligned, configure the radio to its licensed configuration, which may include adaptive coding and modulation, higher modulation mode(s), lower transmit power(s), and ATPC.
No, the PTP850 does not have the BNC connector, but rather a pair of DVM meter lead jacks under a cap on the backside of the unit. You plug the multimeter directly into the probe receptacles.
The various PTP 850 outdoor units have the cap/jacks/wifi port set up slightly different, but the funcionality is exactly the same. When aligning the radios, a DVM measuring DC voltage will read 1.xx volts, where the xx represents the RSSI in dBm. For example, 1.42 volts means the RSSI is -42 dBm.
