Hi David I am 275 km air distance awav from Helmut (what is claimed by Google Maps).
I should be capable of measuring the power much better by gauging my sdr TRX. When in TX, I present my TX-signal on the screen (spectrum display) to watch the effects of predistortion. But I have been somewhat lazy about a correct gauging. I will clean up this. Then, I can report exactly the used power for the next 700B-experiments. I seem to remember, that Helmut told me, not to see the signal anymore on the spectrum, but I am not shure. He can comment on that. I am very happy to make use of your advanced techniques! Software is the future! 73, hb9epu, Alfred On 23.09.2015 01:29, David Rowe wrote: > Hi, > > Wow 50mW is amazing. Once nice feature about digital voice - once you > have enough power any further increases don't help. > > I have managed to get 0 BER over NVIS paths at my radios minimum power > (0.5W). It was annoying as I wanted errors but I couldn't get any! > > How far apart are you and Helmut in km? > > As FreeDV matures over the next few years we will see more Hams using it > even for armchair conversations. The open source API will help - very > low cost for anyone to incorporate in their SDR. > > We have the pleasure of being the pioneers - like the 1920's or 1950s > (AM to SSB) all over again. These transitions only come once every 50 > years. It's nice to be a part of it. > > Cheers, > > David > > On 23/09/15 05:28, wully wrote: >> Hi all >> >> Helmut, dc6ny, and I have done some more tests yesterday. The band >> starts opening again (wonderful: we always want to test 700B). >> As stated earlier, we never had any problem with the 700B-tuning: cohpsk >> locks quicker than the fdmdv, at least, this is the impression we get >> from our experiences. Yesterday, I started to reduce my power (measured >> by an LP-100A just before the antenna coupler) when txing in 700B. >> Helmut detected the signal and I reported about my power seting: Full >> drive started with 58Watts peak. Then I reduced the power to 100mW peak >> (reading the quickly changing "average" of LP-100A). This was the last >> setting, that I could read on the LP-100A, my relative powerseting was >> at 7 out of 256. Then I reduced to 6, then to 5, to 4, to 3, to 2. After >> this experiment, Helmut reported, that he could fully decode the signal >> at 6, but at 5 only about 50% and lower no decoding anymore. We >> estimated, that setting 6 was about 50 mWatt. >> >> We both are very impressed by this result! >> >> Unfortunately, during our experiment at higher power there were some >> people trying to destroy our signal: I have to say, that they were >> sucessful. In this respect, the 1600 was a little less critical. >> But I think that this is just a remark. Against bad guys, one can not fight. >> >> 700B is realy a very good mode. I try to convince more people, to make >> experiments. but it is not so easy, because amateurs today seem to sit >> in their chair and enjoy not to experiment! What a difference to what we >> heard from the amateurs in the twenties! >> >> Great, to hear, that there will be presentations in conferences! >> >> 73, hb9epu >> >> >> On 22.09.2015 04:44, Walter Holmes wrote: >>> I guess I must really be missing something here. :) >>> >>> I have been using 700 and 700B since it was first released in early beta >>> many weeks ago and have NEVER had an issue with tuning, as long as the >>> person at the other end WAS also on frequency. >>> >>> As long as my radio is on the right frequency it locks on very well. >>> >>> It almost sounds like we're trying to solve a problem that doesn't really >>> exist on the air in everyday use. >>> >>> Of course with the Waterfall on a computer it will be many times easier. And >>> use of the QSO Finder to let people know WHAT frequency you're on, it's a no >>> brainer. >>> >>> When you see the carriers and the bandpass filter set to 1.5k, just center >>> it in the waterfall screen, and done. >>> >>> Since we have not had the code to try it on an SM1000 just yet, that may be >>> slightly more difficult, but even still, I would use the dial of the radio >>> to set it to either a known frequency or center up on the sound. >>> >>> Just my 2 cents.. :) >>> >>> Walter/K5WH >>> >>> -----Original Message----- >>> From: David Rowe [mailto:[email protected]] >>> Sent: Monday, September 21, 2015 7:39 PM >>> To: [email protected] >>> Subject: Re: [Freetel-codec2] Tuning Aid 700B mode >>> >>> Just curious - have any of you actually tried 700B OTA? >>> >>> On 22/09/15 09:56, glen english wrote: >>>> how about a modulated output or something from the speaker to assist >>>> tuning- IE a variable tone, or a series of clicks at some frequency as >>>> to provide tuning direction feedback. >>>> >>>> maybe fallng chirps when you are too low, and rising chirps when you >>>> are too high... etc ? >>>> >>>> >>>> On 22/09/2015 8:39 AM, Stuart Longland wrote: >>>>> On 15/09/15 18:42, David Rowe wrote: >>>>>> The CPU load is proportional to the initial freq offset estimation >>>>>> bandwidth. I'm inclined to wait a little and see if this is a real >>> problem. >>>>> Tuning accuracy is likely to be an issue on headless systems or for >>>>> visually impaired operators. >>>>> >>>>> >>>>> --------------------------------------------------------------------- >>>>> --------- >>>>> >>>>> >>>>> _______________________________________________ >>>>> Freetel-codec2 mailing list >>>>> [email protected] >>>>> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 >>>> -- >>>> - >>>> Glen English >>>> RF Communications and Electronics Engineer >>>> >>>> CORTEX RF >>>> & >>>> Pacific Media Technologies Pty Ltd >>>> >>>> ABN 40 075 532 008 >>>> >>>> PO Box 5231 Lyneham ACT 2602, Australia. >>>> au mobile : +61 (0)418 975077 >>>> >>>> >>>> >>>> ---------------------------------------------------------------------- >>>> -------- >>>> >>>> >>>> >>>> _______________________________________________ >>>> 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 >>> >>> >>> ------------------------------------------------------------------------------ >>> _______________________________________________ >>> 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 >> > ------------------------------------------------------------------------------ > _______________________________________________ > Freetel-codec2 mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 ------------------------------------------------------------------------------ Monitor Your Dynamic Infrastructure at Any Scale With Datadog! 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