My motorola RDU2020 radio receives but does not transmit calls

1) You possibly have a bad or nearly dead battery. Transmit takes more energy than receiving. With this in mind, your radio's transmit will fail, if you have a poorly charged or bad battery, when pressing the PTT. Try a battery from a known good radio to see if it eliminates the problem. If so, replace your battery.

2) The radio is either programmed incorrectly or in need of repair. If you have been experimenting with the programmable features, we suggest you walk back through the steps of programming. Here is a link to the user guide: http://www.mytoolstore.com/motorola/rdx_userguide.pdf Programming instructions begin on page 36.

3) If in need of repair. Radios less than one year old should be under warranty, barring any physical or water damage to the unit. Contact the place of purchase or Motorola for warranty instructions.
If the radio is more than one year old you can get it repaired at any dealer offering Motorola repair. (approx. $85 flat rate)

Best regards.