H-DQPSK is a fancy name for what is also known as LSM, which has been supported by OP25 for several years; P25 phase II has also been supported by OP25 for several years.

OP25 cannot in general be tuned manually to a TDMA channel - instead it must be operated in trunked receiver mode - the data needed to descramble the voice frames (for TDMA) are obtained from the 9,600 control channel. OP25 automatically switches to the proper baud rate (6K) for symbol reception on TDMA H-DQPSK channels.

The demod mode (-D cqpsk) must be selected - fsk4 won't work.

Max

On Monday, February 24, 2020, 7:47:08 PM EST, James Qiu <jamesxq@gmail.com> wrote:

Hi,

I'm new to OP25. I'm wondering if and when OP25 will support H-DQPSK demodulation. It's specified in Phase II of P25. I tried -2 option, but it didn't work. I used Anritsu LMR test box as the source.

Thanks

James