Hi David, > I am concerned about blowing up voice-rated SSB PAs with continuous high > average power levels.
Don't be. Almost all Ham Radio rigs, HF and VHF/UHF have the FM mode where they run full power. And, run fans to keep the PA cool. Alan VK2ZIW FT-450D, FT-897, FT-857, IC-910H On Wed, 17 Jun 2020 07:03:16 +0930, David Rowe wrote > Hello List, > > I've been working with Peter, VK3RV on the surprisingly tricky > problem of measuring FreeDV Tx power. > > Over the weekend I built an inline "sampler" and tried a few > averaging options to measure the power of a 700D waveform on my spec- > an. I am using my IC7200 with the drive adjusted so that the ALC > just moves. I am sampling the power between the IC7200 and my ATU, > which is connected to a dipole on 40M. > > I get 75W peak indicated on two bar-graph type power meters (on the > radio and ATU). > > Using "power averaging" and a RMS detector on the spec an over about > 1 minute I get about 40dBm (10W). > > The FreeDV waveforms all have a Peak to Average Power Ratio (PAPR or > crest factor) of around 13dB. > > 1/ Has anyone else tried to measure FreeDV power? > 2/ Does anyone know what the RMS/average power of SSB is (e.g. for a > 100W PEP signal)? > > -/- > > Where I am going with this .... 10W is a lot less than say RTTY or PSK31 > typically puts out. If we can address the PAPR of FreeDV waveforms > by even 3dB that's signficiant extra link margin. On the flip side > I am concerned about blowing up voice-rated SSB PAs with continuous high > average power levels. > > Thanks, > David --------------------------------------------------- Alan Beard OpenWebMail 2.53 _______________________________________________ Freetel-codec2 mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freetel-codec2
