Return-Path: Received: from rly-da04.mx.aol.com (rly-da04.mail.aol.com [172.19.129.78]) by air-da06.mail.aol.com (v121_r4.4) with ESMTP id MAILINDA062-a64497f76d6359; Tue, 27 Jan 2009 16:04:57 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-da04.mx.aol.com (v121_r4.4) with ESMTP id MAILRELAYINDA044-a64497f76d6359; Tue, 27 Jan 2009 16:04:24 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1LRv68-0005Sh-RQ for rs_out_1@blacksheep.org; Tue, 27 Jan 2009 21:03:52 +0000 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1LRv68-0005SY-9G for rsgb_lf_group@blacksheep.org; Tue, 27 Jan 2009 21:03:52 +0000 Received: from smtp814.mail.ird.yahoo.com ([217.146.188.74]) by relay3.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1LRv67-0000qQ-Be for rsgb_lf_group@blacksheep.org; Tue, 27 Jan 2009 21:03:52 +0000 Received: (qmail 34424 invoked from network); 27 Jan 2009 21:03:45 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=btopenworld.com; h=Received:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:In-Reply-To:Subject:Date:MIME-Version:Content-Type:Content-Transfer-Encoding:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=bEHrtJTFdr2kPSYwJGUif4nsLd/kKCKdBnJNGwvICMxcUetth7tC5PlofZbdx7Ln8PsyqNT2aO8/NJoqHj/V7tpxBuVfbnkDK2Fc5bOMgLJi7WyUZIxSdPw9dGCTWqA0VhOVK+uLAe5noInSrCX+A8IhpNhA9dHHABZQxSE7FjA= ; Received: from unknown (HELO JimPC) (james.moritz@86.135.206.173 with login) by smtp814.mail.ird.yahoo.com with SMTP; 27 Jan 2009 21:03:45 -0000 X-YMail-OSG: tx3uGvUVM1nRay3fAFvVUFv7yZliXbmxeSrVfjryaNVbxnS4nUHxG14LiaTI1YZ084rhdPz_ssDIoViul1HD49cts3_vRqTAEwOUoVvzouGo5._4ArK0OtpIiTQDdaqdRepP4V5sPX2beFfq9xjTmdoGV17QJt.Fzo9mocjD70NY8uPx.ajdeGSpU9.kZVKodnJlJEulKQdC_yBWT3yD.VLVhynN6stEmA0hOwQuUBgyj8WFy7.58cleH38Hl68- X-Yahoo-Newman-Property: ymail-3 Message-ID: From: "James Moritz" To: References: <004f01c9809a$708b5c30$0301a8c0@mal769a60aa920>, <497F3902.1070604@sighthound.demon.co.uk> <497F5976.5945.1B872C2@v.d.heide.on-line.de> In-Reply-To: <497F5976.5945.1B872C2@v.d.heide.on-line.de> Date: Tue, 27 Jan 2009 20:59:10 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Windows Mail 6.0.6001.18000 X-MimeOLE: Produced By Microsoft MimeOLE V6.0.6001.18049 DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: PROPAGATION WSPR Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.1 required=5.0 tests=MISSING_OUTLOOK_NAME autolearn=no version=2.63 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-AOL-IP: 193.82.116.20 Dear Klaus, Mal, LF Group, As far as being able to provide the information required in a beacon signal, I think WSPR and QRSS3 are roughly equivalent - they will function with similar signal and broadband noise levels at the receiver, WSPR gives a faster data rate, but QRSS3 requires less bandwidth, probably an advantage when narrow band QRM is present. Both have been used successfully as beacon signals. But at the moment, there is no QRSS equivalent of the WSPR beacon software. This means there are important practical advantages to WSPR. The first thing is that the process is automated. The signal is transmitted, received, decoded, SNR is measured, and the result uploaded to a searchable database, along with every other reception report from all participating stations, so the information is available to anyone in almost real time in a very convenient form. This happens by individual stations setting up a transceiver, running the software, and connecting their PC to the internet (Oh, and remembering to enter their station info in place of K1JT's!). So it is very simple to add your station to a network of beacons, and access the data generated by the network. Using QRSS beacons, the nearest equivalents are the "grabbers", which are a bit more involved to set up. The signals currently have to be interpreted visually; with QRSS3, this requires reviewing 100+ images, each with potentially several signals for an overnight monitoring session, either as they are generated or the next day, a tedious process. Then a report has to be manually written and sent to everyone who might be interested. Visually assessing SNR from this type of image is not very objective at all (hence the "T M O" reporting system). This sort of thing can be done in software (there are plently of CW-reading programs, Spectrum Lab has rather good facilities for calculating SNR), but it does not exist in an easy-to-use package Furthermore, with WSPR each beacon station can transmit and receive during a session, which roughly doubles the number of stations in the network, effectively . The availability of a large number of "channels", with transmit and receive intervals of fixed duration, but randomised occurence, means that little is required to set up the network other than to know what frequency range is going to be used. One could imagine something equivalent for QRSS beacons, but again it does not exist in a convenient form yet. Finally, if a single WSPR transmission is decoded, you have a useful amount of information - station ID, power, location, signal to noise ratio, without any prior knowledge of the station, or other channel of communication. With QRSS3 beacons, you usually only get a callsign (or part of one). No reason you should not send the other data in QRSS3 as well, but it would take a relatively long time to get the complete message, requiring longer "peak" conditions for a marginal signal. In practice, you are often relying on QRSS beacons station publicising their details on the internet in order to positively identify them. So overall, from a theoretical point of view, I don't suppose there are particularly great advantages to a WSPR beacon over a QRSS3 beacon. But in practice, WSPR as a package is quite easy and convenient to use and gives useful results with achievable power levels, at least on 500kHz. It also allows one to get a good night's sleep! There are clearly bug-fixes and improvements that could be made to WSPR, or other modes, but at the moment it is an example of the maxim "I don't want it perfect, I want it Tuesday!" Cheers, Jim Moritz 73 de M0BMU ----- Original Message ----- From: "Klaus von der Heide" To: Sent: Tuesday, January 27, 2009 5:59 PM Subject: Re: LF: PROPAGATION WSPR > > Dear LF Group, > > we should clearly differenciate between all aspects. > > A propagation study does not need any information transfer > via the radio path other than confidence on the identity of > the station in focus. In that case, observing the carrier > is best. So WSPR has no advantage over QRSS. > > On the other hand, WSPR has the advantage of automatic > recording. But that is not an advantage of the mode, it > simply is the lack of a corresponding simple program that > does the same with a QRSS signal. >