Looks like it's working reasonably well, though the 20 meter band fell out
shortly after we all got it installed. More testing tomorrow for sure. :)

-Mooneer K6AQ

On Sat, Dec 19, 2020 at 2:26 PM <[email protected]> wrote:

> Have it loaded and running now.
>
> Working on a couple others as I type to get some end to end testing.
>
> Many thanks David, and best of the holidays.
>
>
> Walter/K5WH
>
> -----Original Message-----
> From: David Rowe <[email protected]>
> Sent: Saturday, December 19, 2020 3:34 PM
> To: [email protected]
> Subject: [Freetel-codec2] FreeDV 1.5 - 700E and OFDM compression
>
> I've been working on a new FreeDV 700E mode, and some compression for
> FreeDV 700D and 700E to increase the average power.  A Christmas present
> for you to play with
>
> 700E is designed to handle fast fading like 700C, but like 700D has
> powerful FEC. My bench tests indicate 700C & E are equivalent on moderate
> fading channels (2Hz dopdler/2ms spread), but on very fast fading (4Hz/4ms)
> 700E does better - 700C & D fall over. 700D works better at lower SNRs on
> slow fading channels.
>
> I've also been testing against compressed SSB, which as Helmut suggests is
> pretty hard to beat, as it's so robust to fading. However 700E is hanging
> on quite well with fast fading, and becomes noise free as the SNR increases.
>
> -/-
>
> The second innovation is compression of the 700C/D/E waveforms, to
> increase average power significantly.
>
> Please be careful adjusting the Tx drive and especially enabling the Tool
> - Options - Clipping. It can drive your PA quite hard.  I have managed 40W
> RMS out of my 75W PEP transmitter.  Make sure your transmitter can handle
> long periods of high average power. My IC7200 and
> FT-817 seem OK.
>
> At the same equivalent peak power - 700D is doing well when compressed SSB
> is -5dB SNR and rather hard on the ears.
>
> -/-
>
> Peter VK3RV, Jose LU5DKI, and Barry VK3BRT tried 1.5.0 last night and
> report it works on real HF channels.
> The latest manual describes the new features:
>
>
> https://github.com/drowe67/freedv-gui/blob/118cb66ee4679518185db871ec0ae68071c406a4/USER_MANUAL.md
>
>
> You can download Windows 32 and 64 bit versions of FreeDV 1.5 here:
>
> http://rowetel.com/downloads/freedv
>
> -/-
>
> I'd be interested in any feedback.  If you have an interesting test case
> (e.g. a bug or comparing SSB to FreeDV), pls send me off air recordings of
> signals (FreeDV Tools-Record File from Radio). That helps me make objective
> comparisons.  Recordings are much more useful to me than anecdotes or
> subjective reports.
>
> Thanks,
> David
>
>
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