From laser@mailman.qth.net Fri Oct 10 15:58:47 2003 From: laser@mailman.qth.net (laser@mailman.qth.net) Date: Fri, 10 Oct 2003 10:58:47 EDT Subject: [Laser] 76km QSO Message-ID: <14f.24e9aedd.2cb82327@aol.com> Hello Group. Well, Autumn / Fall is here and the nights are getting longer. Earlier this week Allan G8LSD and I spotted a fog free British evening with good visibility and took advantage. We successfully made a CW QSO between Butser hill in the county of Hampshire and Ashdown forest in East Sussex. Total distance was 76.1km (apx 47 miles) which extends the current UK record (49.3km) Equipment was G8LSD/P: 3mW @ 670nm and 50mm beam expander. OPT211 on RX. G0MRF/P: 10mW 670nm with OPT210 on receive. The atmosphere was unusually stable with minimal 'scintillation' . Having made the CW QSO (it took over 2 hours to locate each other!) Allan decided to try his 10kHz sampled pulse width modulator. This allowed a cross mode QSO using the lasers and then a 30 minute chat in full duplex with the laser in one direction and the 70cm talkback in the other. Great fun. 73 David G0MRF http://www.g0mrf.freeserve.co.uk/laser.htm --- StripMime Report -- processed MIME parts --- multipart/alternative text/plain (text body -- kept) text/html The reason this message is shown is because the post was in HTML or had an attachment. Attachments are not allowed. To learn how to post in Plain-Text go to: http://www.expita.com/nomime.html --- From laser@mailman.qth.net Fri Oct 10 18:52:08 2003 From: laser@mailman.qth.net (Jim Moss) Date: Fri, 10 Oct 2003 10:52:08 -0700 (PDT) Subject: [Laser] 76km QSO In-Reply-To: <14f.24e9aedd.2cb82327@aol.com> Message-ID: <20031010175208.27601.qmail@web80409.mail.yahoo.com> CONGRATS!!!! Jim N9JIM/6 --- G0MRF@aol.com wrote: > Hello Group. > > Well, Autumn / Fall is here and the nights are getting longer. > > Earlier this week Allan G8LSD and I spotted a fog free British evening with > good visibility and took advantage. > > We successfully made a CW QSO between Butser hill in the county of Hampshire > and Ashdown forest in East Sussex. > > Total distance was 76.1km (apx 47 miles) which extends the current UK record > (49.3km) > > Equipment was G8LSD/P: 3mW @ 670nm and 50mm beam expander. OPT211 on RX. > G0MRF/P: 10mW 670nm with OPT210 on receive. > > The atmosphere was unusually stable with minimal 'scintillation' . > Having made the CW QSO (it took over 2 hours to locate each other!) Allan > decided to try his 10kHz sampled pulse width modulator. This allowed a cross > mode > QSO using the lasers and then a 30 minute chat in full duplex with the laser > in one direction and the 70cm talkback in the other. > > Great fun. > > 73 > > David G0MRF > > HREF="http://www.g0mrf.freeserve.co.uk/laser.htm">http://www.g0mrf.freeserve.co.uk/laser.htm > > > --- StripMime Report -- processed MIME parts --- > multipart/alternative > text/plain (text body -- kept) > text/html > The reason this message is shown is because the post was in HTML > or had an attachment. Attachments are not allowed. To learn how > to post in Plain-Text go to: http://www.expita.com/nomime.html --- > _______________________________________________ > Laser mailing list > Laser@mailman.qth.net > http://mailman.qth.net/mailman/listinfo/laser From laser@mailman.qth.net Fri Oct 10 22:23:21 2003 From: laser@mailman.qth.net (G. Horvath) Date: Fri, 10 Oct 2003 14:23:21 -0700 Subject: [Laser] 7.4km QSO References: <14f.24e9aedd.2cb82327@aol.com> Message-ID: <003201c38f74$bbbe6020$6c02a8c0@service> A few days ago VE7DDR/CN88dw and VE7DXG/CN88cx made a 7.4km QSO using two Ramsey laser kits. The path was over water on a nice calm evening. Took us about 30 minutes to get aligned, and signals were quite strong. There was a lot of "shimmer" visually, but the AM signals were nice and steady in the receiver. This is our best DX yet. VE7DDR took some photos of the setups, I'll post them on the net when they become available. We're looking forward to breaking the 10km barrier pretty soon. (I also made a Laser QSO during the ARRL September VHF Contest with VA7AA. The distance was about 20'.) 73, Gabor, VE7DXG From laser@mailman.qth.net Sat Oct 11 13:04:25 2003 From: laser@mailman.qth.net (Richard Burrows) Date: Sat, 11 Oct 2003 13:04:25 +0100 Subject: [Laser] 76km QSO References: <14f.24e9aedd.2cb82327@aol.com> Message-ID: <000d01c38fef$d09e5920$0100a8c0@RICHARD> David and Allen Well done to you both, what next I wonder? I'm still trying to achieve a cloud bounce QSO :( Richard - G8BYI ----- Original Message ----- From: To: Sent: Friday, October 10, 2003 3:58 PM Subject: [Laser] 76km QSO > Hello Group. > > Well, Autumn / Fall is here and the nights are getting longer. > > Earlier this week Allan G8LSD and I spotted a fog free British evening with > good visibility and took advantage. > > We successfully made a CW QSO between Butser hill in the county of Hampshire > and Ashdown forest in East Sussex. > > Total distance was 76.1km (apx 47 miles) which extends the current UK record > (49.3km) > > Equipment was G8LSD/P: 3mW @ 670nm and 50mm beam expander. OPT211 on RX. > G0MRF/P: 10mW 670nm with OPT210 on receive. > > The atmosphere was unusually stable with minimal 'scintillation' . > Having made the CW QSO (it took over 2 hours to locate each other!) Allan > decided to try his 10kHz sampled pulse width modulator. This allowed a cross mode > QSO using the lasers and then a 30 minute chat in full duplex with the laser > in one direction and the 70cm talkback in the other. > > Great fun. > > 73 > > David G0MRF > > http://www.g0mrf.freeserve .co.uk/laser.htm > > > --- StripMime Report -- processed MIME parts --- > multipart/alternative > text/plain (text body -- kept) > text/html > The reason this message is shown is because the post was in HTML > or had an attachment. Attachments are not allowed. To learn how > to post in Plain-Text go to: http://www.expita.com/nomime.html --- > _______________________________________________ > Laser mailing list > Laser@mailman.qth.net > http://mailman.qth.net/mailman/listinfo/laser From laser@mailman.qth.net Thu Oct 16 21:54:48 2003 From: laser@mailman.qth.net (laser@mailman.qth.net) Date: Thu, 16 Oct 2003 16:54:48 EDT Subject: [Laser] Digikey diodes Message-ID: <6d.1b034746.2cc05f98@aol.com> A couple of months ago there was a brief mention of the 120mW IR laser diodes from digikey. Has anyone bought one of them and managed to get it mounted safely and operational? I note that they are manufactured by Sharp. Does anyone know the Sharp part number so I can locate a data sheet? At $20 they are excellent value, although a little more dangerous than I'm use to. 73 David G0MRF --- StripMime Report -- processed MIME parts --- multipart/alternative text/plain (text body -- kept) text/html The reason this message is shown is because the post was in HTML or had an attachment. Attachments are not allowed. To learn how to post in Plain-Text go to: http://www.expita.com/nomime.html --- From laser@mailman.qth.net Sun Oct 26 20:27:05 2003 From: laser@mailman.qth.net (Andrew T. Flowers, K0SM) Date: Sun, 26 Oct 2003 15:27:05 -0500 Subject: [Laser] Photodiode question Message-ID: <3F9C2E19.3070701@alltel.net> Quck question-- I'm going to make another order to digikey, and I would really like to blow $40 on a big photodiode--thinking about the PDB-V112 :-) Do I want one optimized for photoconductive or photovoltaic operation to use in the K3PGP front end? It looks like the PD is in photoconductive mode in this design, but how much does this really matter? Regarding the PDB-V112, the NEP looks decent for it's active area (1cm^2), and the BNC connector looks handy for keeping out RFI. It is optimized for photovoltaic operation, but like I said, is this a big deal? Andy K0SM/2