I haven't seen them mentioned, and they are not inexpensive but some models of the ANAN line of SDR transceivers https://apache-labs.com/ have phase coherent dual receivers with the ability to do phasing in the software.
I have the Flex 6700 which also has the dual receive aspect but no phasing control in the software. I know the Flex (and perhaps the ANAN) doesn't support any kind of spectral recording. Don VE6JY On Wed, Jan 16, 2019 at 4:33 AM Nick Hall-Patch <nhp@ieee.org> wrote: > Thanks for addressing this Mark, and saving me > fine tuning my own comments, which were essentially: > > Is SDR phasing live any better than hardware > phasing? If it's not, then all you're doing is > replacing a piece of hardware with perhaps a > heavier duty computer, are you not? > > Phasing files as they are played back would be > the technological game changer. I suspect that > doing that means recording a different kind of > .wav file that includes a counter in its header, > so that samples recorded from one locked receiver > can be matched up with samples from the other > during playback. More informed folks than I > could comment on the feasibility of that, or whether it exists already. > > Would it make any difference to the average > DXer? I don't seem to have time to play back > some of the files from my good openings at home, > let alone from DXpeditions. The > enhanced ability to winkle out more DX from > files that I'm not listening to anyway may not be > all that helpful, hi. (of course, if I stopped > bloviating, there might be more time...) > > I seem to recall one SDR manufacturer a few years > ago thinking that there would be little market > for such a device, even if you provided all > manner of hand-holding software, which is the > quite expensive to produce, especially if you want it to function well. > > best wishes, > > Nick > > > > > > > At 04:06 2019-01-16, Mark Connelly via IRCA wrote: > > > >I would be willing to have a receiver that just > >saved half the MW bandwidth, e.g. 700 kHz, in > >capture files if it had the I/Q streams from the > >two receivers.à But with receivers doing 3, 6, > >and more MHz of capture these days, why can't we > >get the whole 510-1710 stretch? > > > >Basic requirements: > > > >*** Phasing can be done after the fact on > >capture files both manually and, when channels > >are reasonably similar, automatically. > > > >*** The two receivers can be slaved to each > >other for diversity and phasing applications or tuned independently. > > > >*** There must be the provision for separate antenna inputs. > > > >*** User can save null solution data to an INI > >file that can be recalled later.à This file > >should be plain text suitable for importation > >into antenna-testing technical articles, DXpedition reports, etc. > > > >You need to be able to adjust both gain of each > >channel and the delta-phase / delta-time between > >them.à You are not always using identical gain > >and pattern antennas. In fact you could be using > >two opposite ends of the same SuperLoop or > >DKAZ.à East end could have 880 WCBS at S-9 and > >882 UK at S-8; west end might have WCBS S9+20 > >and UK S-5.à So why should you not be able to > >put 20 dB attenuation on the west end to make > >WCBS S-9 and then phase it against the east end > >to provide vastly cleaner pick-up of 882 UK?à I > >can certainly do that with the Quantum Phaser and several homebrew models. > > > >If you can adjust after the fact on capture > >files you can run several different gain / phase > >scenarios on, let's say, a graveyard > >channel.à By moving the null around the > >compass, as with a conventional rotatable loop, > >you could pull as many as 6 to 8 different ID's > >out of a single channel at a particular time. > > > >You could also think about applying a gain / > >phase curve.à Let's say you used an (A vs. B) 8 > >dB delta gain / 100 ns delta time solution to > >take down 770 WABC and 6 dB / 90 ns to take out > >880 WCBS.à In-between frequencies could be > >adjusted "on the curve".à 820 WNYC, in a > >similar direction as 770 and 880, could be > >expected to null at something like 7 dB delta > >gain / 95 ns delta time.à This sort of > >mathematical manipulation of the data streams > >could help to broadband the nulling pattern when > >using two antennas that don't quite fit the > >textbook scheme of spatially-separated elements > >of identical gain and pick-up pattern. > > > >Phasing only during live DX is not the game > >changer or killer app here.à It's nice maybe to > >eliminate one box on the table but what we > >really want is post facto phasing as well as live DX use. > > > >The baby steps are being taken but > >ready-for-prime-time software and hardware > >hasn't arrived yet as far as I can tell.à Ham > >DXpeditions / contest stations, MW guys in > >Finland etc. would be all over it if it had. > > > >Mark Connelly, WA1ION > >South Yarmouth, MA > > > ><< > >A couple of drawbacks for the Afedri: > > > >(1) As of a year ago (I have not checked since), > >the phasing only worked on the live signals. No > >phasing was possible on a recorded file. > > > >(2) It has only a 12 bit converter so is not top of the line. > > > >And something that needs verification: the > >Afedri was only spec'ed to record 900 kHz of > >bandwidth. I see it has recently been changed to > >1100 kHz. That's enough for me if it performs as advertised. > > > >Chuck > > >> > > > ><< > >Did I miss something?à As far as I can tell, > >nothing discussed here comes close to what we > >need - the ability to phase null synchronized RF > >spectrum captures.à Everything described here > >is no different than using two receivers (SDR or > >analog) on different antennas, or > >phasing/combining two antennas into one > >receiver, for the purposes of live monitoring > >and making single RF spectrum captures.à While > >it is possible to make two RF spectrum captures > >using two SDR receivers simultaneously, then > >perfectly synchronizing playback of the two RF > >spectrum captures for diversity reception (i.e. > >audio from one RF spectrum capture in the left, > >the other in the right), it's difficult to get > >the audio from each spectrum capture in sync and > >the results usually not worth the effort.à The > >WiNRADiO Excalibur has three receivers in one, > >but they all operate off the same antenna.à So > >the Excalibur can be used for 'diversity > >reception' of parallel frequencies by tuning Rx1 > >to 1053 TalkSport and Rx2 to 1089 TalkSport, > >then combining the audio using the Mix functions > >of the Excalibur for example, but it's not > >really diversity reception by definition which > >would have two SDR receivers each with their own > >antenna.à I see nothing groundbreaking here. > > > >-- > >Bruce Conti > >B.A.Conti Photography www.baconti.com > >ÃÂBAMLog! www.bamlog.com > > >> > > > ><< > >Hi Mark, I have one of the newer Afedri V3.0 > >dual input radios here. I bought it out of > >curiosity and am pleased with how well it > >phases. It only has a 1.2Mhz span width in dual > >channel mode, but that gets most of MW. It works > >as well as phased loops/flags but without as > >much loss. I use it with HDSDR after setup with > >the connection tool provided with the Afedri > >radio. SDR# is another software that works, but > >I haven't figured out how to get more than a 192K span from it. > > > >In the Afedri, the 2 ports can be combined, with > >the ability to change the phase but not the > >signal levels. So, your antennas need to be the > >same and cable lengths need to be equal also (or > >length adjusted to prebalance the phase). > > > >Dave Aichelmanà à à à N7NZHà à à à Grants Pass, Oregon > >__._,_.___ > > >> > > > >The subject of SDRs containing two phase-locked > >receivers came up recently on the Topband (160m > >ham) list ( > >http://lists.contesting.com/archives//html/topband/2019-01/threads.html > ). > > > >The discussion dealt primarily with diversity > >reception: audio from antenna A's RF goes to > >your left headphone, antenna B to the right.? In > >some cases a weak or interfered-with signal that > >isn't quite readable on either channel > >independently can "pop out of the mud" when both > >channels are presented, one to the left and one > >to the right as mentioned. Typically you're on > >the same frequency, mode, bandwidth, and AGC for > >this.? Maybe you use USB one channel and LSB the > >other if the interference is different owing to > >antenna pick-up patterns.? For MW DX, sometimes > >two different frequencies would be fed to the > >headphones for quick comparison of parallel > >audio content (e.g. Spain 684 & 855, Cuba 670 & 710, Japan 747 & 774). > > > >More of interest to me is phasing based in the > >receiver.? This should be available under > >complete (manual) operator control of each > >channel's gain and phase / time delay.? There > >should be a way to save successful null or peak > >set-ups to a look-up table text file that can be > >invoked later to speed up DXing.? The file > >should also be importable into Excel / Word / > >Access / PowerPoint for producing technical > >articles.? Additionally the receiver should > >provide a degree of auto-nulling, at least when > >the two synchronized receivers are getting the > >same dominant "pest" signal (or noise) a > >reasonable amount above co-channel and adjacent interference. > > > >The subject has been chatted up here before and > >I think that one or more receivers > >hardware-capable of this were out there but > >there was no clear software solution, at least > >anything that has been adequately "road tested" > >by cutting edge contester hams and the top MW > >talent in Scandinavia, North America, and east Asia. > > > >If there is new information on this topic, feel free to comment. > > > >Mark Connelly, WA1ION > >South Yarmouth, MA > > > >These are some posts recently appearing on the > >Topband list under the "Re: Topband: Dual RX SDR > >receivers (diversity capable)" header. > > > ><< > >Have you looked at > >http://www.afedri-sdr.com/index.php/new-afe822x-sdr-net-dual-channel ? > > > >73 > >Nick > >VE7DXR > > >> > > > ><< > >Cross Country Wireless SDR-4++ dual diversity SDR general coverage > receiver > > > >Digitally signed mail - John? M0ELS > > >> > > > ><< > >Hi Bjorn > > > >If you are interested, I have a dual Softrock > >160m SDR receiver (two receivers in one diecast > >box) that was built up about ten years ago or so > >for diversity reception, using Alex VE3NEA?s > >Rock 2.0 diversity version ? see http://www.dxatlas.com/Download.asp. > > > >Owing to family/business pressures I never got > >around to using it. My recollection is JC N4IS > >may have built up something similar? > > > >The receiver is just sitting on a shelf here and > >I am happy to part with it. Also have a M-Audio > >D44 professional soundcard that was going to used with it. > > > >Vy 73 > > > >Steve, VK6VZ > > >> > > > >_______________________________________________ > >IRCA mailing list > >IRCA@hard-core-dx.com > >http://montreal.kotalampi.com/mailman/listinfo/irca > > > >Opinions expressed in messages on this mailing > >list are those of the original contributors and > >do not necessarily reflect the opinion of the > >IRCA, its editors, publishing staff, or officers > > > >For more information: http://www.ircaonline.org > > > >To Post a message: irca@hard-core-dx.com > > Nick Hall-Patch > Victoria, BC > Canada > > _______________________________________________ > IRCA mailing list > IRCA@hard-core-dx.com > http://montreal.kotalampi.com/mailman/listinfo/irca > > Opinions expressed in messages on this mailing list are those of the > original contributors and do not necessarily reflect the opinion of the > IRCA, its editors, publishing staff, or officers > > For more information: http://www.ircaonline.org > > To Post a message: irca@hard-core-dx.com > >
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