The operating mode options for the TIDRADIO TD-H3 Plus appear to have been changed from the previous version of the TD-H3. The previous version has three different modes of operation for amateur radio frequencies, GMRS, or Normal. The TD-H3 Plus has two options, one for amateur radio (HAM), and Normal. It appears the GMRS mode has been removed, and when you select the second option (Normal), the GRMS transmit frequencies are included in that mode.   

Below is the procedure to unlock those modes.

Amateur Radio Only:

1. Ensure the radio is powered off.
2. Hold down the PTT and the STAR buttons while powering on the radio. 
3. After powering on the radio, you will see a menu with three options for HAM, GMRS, and Normal.
4. Press #1 to put the radio in HAM only mode, and then press YES to confirm the setting. 
5. The radio will restart, and the radio will transmit and receive on the 2-meter, 70-centimeter, and 1.25-meter bands. 

Normal:

1. Ensure the radio is powered off.
2. Hold down the PTT and the STAR buttons while powering on the radio. 
3. After powering on the radio, you will see a menu with three options for HAM, GMRS, and Normal.
4. Press #3 to put the radio in HAM only mode, and then press YES to confirm the setting. 
5. The radio will restart, and the radio will transmit and receive on the 2-meter, 70-centimeter, 1.25-meter, and GMRS frequencies.