Sure rafael. I'm also looking forward to be able to buy my own WB50... Is it availale yet? If not, you know when will it be?
2008/11/12, rafael2k <[EMAIL PROTECTED]>: > Hello people, > I'm following the discussion about the Soft-DVB, and I'm thinking about use > of > the WBX0510 daughterboard (50 MHz to 1 GHz) w/ Soft-DVB - Will then be > possible to transmitt in any VHF/UHF channel? > > Bye, > Rafael Diniz > > Em Tuesday 11 November 2008, Vincenzo Pellegrini escreveu: >> Martin , >> sorry for the delay. My exams seem to have gone well even if it's not >> official yet. I also had to do a demo for a company I have a temporary >> contract with for developing some gnuradio based gsm-r security >> sentinels. Also the demo was smooth. (i already listed the project on >> the gnuradio wiki) >> so i really hope i'll be able to prepare the 8Mhz stream for you >> within the next 2/3 days. Would this still be useful? >> >> 2008/11/3, Martin DvH <[EMAIL PROTECTED]>: >> > On Mon, 2008-11-03 at 14:13 +0100, Martin DvH wrote: >> >> ________________________________ >> >> >> >> > Van: [EMAIL PROTECTED] >> >> >> >> [mailto:[EMAIL PROTECTED] >> >> Namens Vincenzo Pellegrini >> >> >> >> > Verzonden: maandag 3 november 2008 0:16 >> >> > Aan: Martin DvH >> >> > CC: discuss-gnuradio >> >> > Onderwerp: [Discuss-gnuradio] Re: Soft-DVB DVB-T transmitter >> >> > >> >> > >> >> > This is Great... :) >> >> > >> >> > Yup, the playback cannot be smooth because of the wrong throughput, >> >> >> >> definitely. >> >> >> >> > Did you use the USRP1 with interpolation factor = 16 ? >> >> >> >> Yes I did. >> >> >> >> > I can prepare a modulated signal with the correct throughput for >> >> >> >> you.. this is not a problem... :) >> >> >> >> Please do, this would be great. >> >> >> >> > what hard disc are you playing your signal back from? >> >> >> >> Internal 2.5" harddisk of my acer 6930 notebook (Aspire 6930G-734G32BN >> >> LX.AVB0X.135) >> >> 2.5" 320GB HDD 5400rpm, SATA >> > >> > I checked now. It is a: >> > Western digital Scorpio 320 GB SATA (WDC WD3200BEVT-22ZCT0) >> > 2.5-inch SATA Hard Drive 320 GB, 3 Gb/s, 8 MB Cache, 5400 RPM >> > >> > Benchmark from tomshardware (h2benchw 3.6): >> > http://www.tomshardware.com/charts/2-5-hard-drive-charts/Minimum-Read-Tra >> >nsfer-Performance,687.html minimum read transfer rate 33.5 MB/sec >> > average read transfer rate 52.2 MB/sec >> > maximum read transfer rate 68.2 MB/sec >> > >> >> I am not at home right now So I can't check the exact brand and model >> >> of >> >> the >> >> harddisk. >> >> It can do around 38 MB/sec so this is just enough (required 32 MB/sec) >> >> >> >> I also have 4GB of memory in this notebook, so I think it will buffer >> >> the complete file. >> >> >> >> I had to use my notebook because with my desktop PC (ASrock >> >> 939-DUAL-SATA2) >> >> The USB TX bandwidth is less then 32 MB/sec. >> >> (Which is strange because I CAN receive 32 MB/sec) >> >> I get UuUuUu on this machine when useing interpolation 16, so unusable. >> >> >> >> Regards, >> >> Martin >> >> >> >> > regards >> >> > >> >> > vincenzo >> >> > >> >> > >> >> > 2008/11/3 Martin DvH <[EMAIL PROTECTED]> >> >> >> >> Hi, >> >> >> >> > > In fact: 8 complex Msps implement a 7 MHz channel while >> >> >> >> 9.142857143 >> >> >> >> > > complex Msps implement an 8 MHz channel. >> >> > > Just try to go as close as possible to such sampling >> >> >> >> frequency by >> >> >> >> > > using USRP2 and let me know what happens... it could >> >> >> >> turn out that we >> >> >> >> > > need a resampler block. >> >> > >> >> > So if I use a fractional rate resampler with interpolation >> >> >> >> factor >> >> >> >> > 10/8=1.25 I get a 7 Mhz channel with 10 Msps samplerate. >> >> > If I use a fractional rate resampler with interpolation >> >> >> >> factor >> >> >> >> > 10/9.142857143=1.09375 I get a 8 Mhz channel with 10 Msps >> >> >> >> samplerate >> >> >> >> > If I use a fractional rate resampler with DECIMATION >> >> >> >> factor >> >> >> >> > 9.142857143/8=8/7=1.142857143 I get a 8 Mhz channel with 8 >> >> >> >> Msps >> >> >> >> > samplerate with the out-of-band skirts folded back at the >> >> >> >> sides. >> >> >> >> > Would be interesting to see if this last one works with a >> >> >> >> USRP1. >> >> >> >> > I'll let you know how the experiments go. >> >> >> >> I resampled and scaled your ofdm_40.dump file so it now will >> >> use 8 Mhz bandwidth with a 8 Msps samplerate. >> >> The reception never can be perfect this way but it seems >> >> good enough for >> >> tests. >> >> >> >> My USB DVB-T receiver receives the transport stream without >> >> problems. >> >> Mplayer playes the stream without problem for two loops and >> >> then crashes >> >> with a broken frame. >> >> My standalone settopbox DVB-T receiver now also receives the >> >> stream. >> >> (8 MHz channel on UHF) >> >> It has big problems displaying it. Sound is only a chop of >> >> sound now and >> >> then and video stops, then runs for a second, then stops >> >> again. >> >> >> >> I think this is because the timestamps and framerate >> >> (playout speed) >> >> don't match the data throughput of the MPEG stream anymore. >> >> (It is getting the stream too fast) >> >> >> >> I put my resampled RF file at: >> >> >> >> http://www.olifantasia.com/projects/gnuradio/mdvh/OTA/DVB-T/ofdm_40_bw8M >> >>hz_s amplerate_8Msps_cshort.raw >> >> >> >> format is complex signed short integers (I 16 bit, Q 16 bit) >> >> at 8 >> >> Msamples/sec. >> >> >> >> >> >> Greetings, >> >> Martin >> >> >> >> > > more details will follow as soon as I find some time... >> >> > >> >> > Thanks and success with your second group of tests. >> >> > >> >> > Martin >> >> > >> >> > > best regards and greetings >> >> > > to all fellow GNURadioers >> >> > > >> >> > > vincenzo >> >> > > >> >> > > PS >> >> > > Rafael, just have a look back a this thread and you'll >> >> >> >> find all the >> >> >> >> > > info you need to do your test broadcast. Thanks for your >> >> >> >> interest >> >> >> >> > > 2008/10/31 Martin Dudok van Heel >> >> >> >> <[EMAIL PROTECTED]> >> >> >> >> > > Hi Vincenzo. >> >> > > How are things going with your exams. >> >> > > >> >> > > I hope well. >> >> > > >> >> > > Thanks for your help so far. >> >> > > >> >> > > I finally got your DVB-T dump streams working. >> >> > > I first tried using an undersampled basicTX but >> >> >> >> never got it >> >> >> >> > > to work. >> >> > > (use a niquist mirror in the VHF range on >> >> >> >> channel 11 or 12 >> >> >> >> > > (219.5 Mhz or 226.5 Mhz)) >> >> > > >> >> > > I now use a RFX900 and that works with a >> >> >> >> pinnacle PCTV-Solo >> >> >> >> > > 72e usb DVB-T receiver card plugged into my PC. >> >> > > I use 858.0 Mhz (channel 69) >> >> > > I used a 10 dB attenuator on the antenna output >> >> >> >> to limit >> >> >> >> > > output power. >> >> > > I also modified the RFX900 to enable >> >> >> >> transmitting outside of >> >> >> >> > > the ISM band. (disable saw-filter. add 220 pF >> >> >> >> capacitor) >> >> >> >> > > Apparantly the pinnacle 72e can receive 7 Mhz >> >> >> >> channels on the >> >> >> >> > > UHF channels. >> >> > > My standalone settopbox DVB-T receiver can't >> >> >> >> handle it. >> >> >> >> > > I noticed you don't use the full possible range >> >> >> >> in your 16 bit >> >> >> >> > > streams. >> >> > > (only goes from -80 to +80 while you could use >> >> >> >> -8192 to 8192) >> >> >> >> > > Is this on purpose? >> >> > > I can multiply samples by 64 and get a cleaner >> >> >> >> signal. (But >> >> >> >> > > also more output power) >> >> > > >> >> > > >> >> > > I do have a request, I hope it is not too much >> >> >> >> work. >> >> >> >> > > Could you make a stream with 10 Msamples/sec >> >> >> >> samplerate and 8 >> >> >> >> > > Mhz wide channel. >> >> > > This way I can use standard standalone DVB-T >> >> >> >> receivers and >> >> >> >> > > don't have the 7Mhz bandwith on UHF problem. >> >> > > >> >> > > For the 10 Msps stream I would have to use my >> >> >> >> USRP2 to output >> >> >> >> > > it. >> >> > > It has a 100 Mhz DAC (in stead of 64 Msps in the >> >> >> >> USRP1) >> >> >> >> > > It has a gbit ethernet connection for the >> >> >> >> samples, so I can go >> >> >> >> > > up to 25 Msps. >> >> > > It can only do fixed interpolation rates so I >> >> >> >> have to choose >> >> >> >> > > from the table below. >> >> > > (8 Msamples/sec is not supported on the USRP2) >> >> > > >> >> > > >> >> > > USRP2 >> >> > > dac_rate interp ethernet_sample_rate >> >> > > 100 4 25 >> >> > > 100 5 20 >> >> > > 100 6 16.67 >> >> > > 100 7 14.29 >> >> > > 100 8 12.5 >> >> > > 100 9 11.11 >> >> > > 100 10 10 <----I think 10 >> >> >> >> Msamples/sec >> >> >> >> > > should be optimal >> >> > > 100 11 9.09 >> >> > > 100 12 8.33 >> >> > > 100 13 7.69 >> >> > > 100 14 7.14 >> >> > > >> >> > > >> >> > > I think 10 Msamples/sec would be a good >> >> >> >> candidate. >> >> >> >> > > Have you also tried using 8 Msamples/sec on the >> >> >> >> USRP1? >> >> >> >> > > I know there would be no room left for IF >> >> >> >> channel filtering, >> >> >> >> > > but it could in theory still work. >> >> > > If this works I would also very much appreciate >> >> >> >> a 8Mhz >> >> >> >> > > bandwidth stream with 8 MSPS samplerate so I can >> >> >> >> demonstrate >> >> >> >> > > with a standard USRP1. >> >> > > >> >> > > Thanks for your help so far. >> >> > > I appreciate it very much. >> >> > > >> >> > > And good luck with your exams. >> >> > > >> >> > > Have a nice weekend. >> >> > > >> >> > > Greetings, >> >> > > Martin > > > -- > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- > Ciência da Computação @ Unicamp > Rádio Muda, radiolivre.org, TV Piolho, tvlivre.org, > www.midiaindependente.org > Chave PGP: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x2FF86098 > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- > > -- Vincenzo Pellegrini _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
