[DonRotolo]

Tether the robot and make sure the OI and RC radios are really on the same channel. The RC radio only changes channel when tethered.

Make sure the metal antennas are not damaged. If they are, you shoudl repair them.

Note that there is an antenna inside the plastic box. Having that antenna next to metal will harm its performance. (No matter what, the radios should work when a few feet apart though...)(Ditto for RFI: At 4 feet, RFI is highly unlikely to be an issue, FM capture is powerful)

Check the DE-9 cables, replace them or ohm them out (including shorts from one conductor to any other)

Try those & let us know.

Don

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