820s Rebooting

We had a radio on the tower that the techs forgot to turn TX MUTE to OFF so it would broadcast a signal.  I turned the TX MUTE to OFF and the ethernet port on the cisco switch began flapping, originally I didn't put 2 and 2 together and think that turning the TX MUTE to OFF had anything to do with this.  So we replaced cables you name it, brought it in the office and doing the same thing ethernet flapping because radio is restarting.  I then got an RMA from Cambium and had our Distributor send us a new radio.  I got it in today and began programming it and was working great, I then turned TX Mute to OFF and the radio started rebooting.  I was able to access the GUI quick enough to reset to factory defaults, and radio started acting fine, so I did NOT program anything except for turn the TX MUTE to OFF and the radio started rebooting yet again.  I have tried 100 different ways to program this radio and same the result just recycles over and over.  

Has anyone ever seen this happen before?  I have about 20 links in the air and have not seen this issue before.  Firmware is


Could you please try the below steps and see if that helps,

1. If you are using same switch to access both the radios at a time, try removing the switch and connect only one radio and see.

2. Power off the other radio and Turn OFF the Tx Mute on the problamatic radio and see if it still rebooting.

3. Remove the Inband Management if it is configured and connect on the Management port and check.

4. Try upgrading the radio software to 8.3 and check.

If you are still facing the issue then please feel free to contact our support team to assist you further.


Sanjay Kumar.

Turn off the Keep Alive feature on the Cisco switch port.


We just experienced the exact same issue.  We think it happened because XPIC was enabled with no antenna attached.  We muted one of the radios and the rebooting stopped.  Maybe the noise cancellation algorithims were very confused because there was little if any cross polarization isolation.  Whatever it was,, muting one of the radios worked.  Hopefully this will not happen out in the wild with the dishes attached.

Is there any particular reason why you un-muted the radios while they are not attached to the antennas?

Allowing the radios to transmit without antennas can be dangerous.


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