FreeDV power output

EA4GLI

I was trying FreeDV on HF (20m and 15m) yesterday and the power output is very low regardless of the Power output that I select on SmartSDR.
Max power I get out of the radio is 25w.
I then checked AM and on 20m all I get is 16w.
On FM I get full 100w. Also get full power on DStar.

The voltage draw from the radio is also lower so it is like the software is using a governor.


I checked with a couple of 6xxx owners and they are also experiencing the same issue.

Thanks in advance for the help.

Jim Gilliam

Remember on AM, for 100% modulation the peak power is 4 times the average power. The maximum average power you can expect on AM, therefore, is 25 Watts. 16 Watts seems very low. Were these power levels checked with a dummy load?

JIm, K6QE

EA4GLI

No dummy load. I measured with the digital meter on the Expert 1k.
I will check with dummy load.

What about on FreeDV? What power are you getting?

Tim - W4TME

Your radio is not broken.  For proper operation of FreeDV, you drive your transmitter to an average power of about 20% of it's PEP power. You do this because there is a 8-12 dB peak-to-average power ratio in the FreeDV HF modem. Over-driving will reduce the received S/N so we limit the power output in software.

EA4GLI

Thank you Tim for the quick response!

Tim - W4TME

De nada, mi amigo.

EA4GLI

Hey Tim, did you already made the arrangements to bring my maestro in person to Barbados? We are awaiting here with some nice cold drinks!

Tim - W4TME

The offer is very tempting.  I could use a nice cold **** drink about now.

EA4GLI

What do you mean offer?? It is a formal invitation. Get your **** over here, housing and sustenance is taken care of!!