Hi Michael, FB on getting your SM1000 up on the air - lets have a QSO some time!
Adjusting so your ALC just moves, and 20-25 watts average power for a 100W PEP rig is a useful rule of thumb for FreeDV 1600. The classic "rookie mistake" is overdriving the SSB tx, which causes clipping and a poor bit error rate at the receiver. Make sure any speech compression is off too. The best way to adjust your tx drive is monitor the SNR of the signal using a 2nd rx and the FreeDV GUI program. For example when I tx with my IC7200, I have a FT817 nearby with no antenna and the RF gain wound down. I feed the rx audio into my laptop and monitor the scatter diagram and SNR. Incidentally, with my IC7200 I can't seem to get better than 20dB, perhaps due to it's sharp tx filtering. I have a video that demonstrates this (and explains scatter plots): http://www.rowetel.com/blog/?p=3109 Cheers, David On 25/07/15 23:05, Michael Carey wrote: > Hi Everybody, > > I've been building up a set of SM1000 cables for a few of my different > HF radios. The main radio I use at home is an Icom IC-7100. > I understand you set the input level to the radio so the AGC indication > barely moves and make sure you don't stress the output stage too much... > I've settled on around 30W output. > > I find that the AGC indication on my IC-7100 tends to jump around a > little when transmitting the FDMDV signal. > Can I use the test tone to set the transmit level and be confident that > this is OK for FDMDV? > > 73 > > Michael. > VK5ZEA > > ------------------------------------------------------------------------------ > _______________________________________________ > Freetel-codec2 mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > ------------------------------------------------------------------------------ _______________________________________________ Freetel-codec2 mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freetel-codec2
