I've never been able to get the doppler tracking quite right using SatPC32. Either that or the stations I'm trying to copy aren't using computer doppler control and that kills some of my advantage in using it. Right now I'm doing some station reconfiguration and I've also had some issues with the 70cm transmit side of my antennas.I hope to work this out and be a regular user of AO-7 and VO-52. 73, Michael,W4HIJ ----- Original Message ----- From: "Anthony Monteiro" aa2tx@comcast.net To: "Auke de Jong" sparkycivic@shaw.ca; "AMSAT-BB" amsat-bb@amsat.org Cc: aa2tx@amsat.org Sent: Friday, July 18, 2008 7:55 PM Subject: [amsat-bb] Re: where all the users
At 08:46 PM 7/17/2008, Auke de Jong wrote:
I can only offer my own reason for being absent from VO-52 and AO-7: I find keeping-up with the doppler-tuning of these LEO-orbits to be frustrating. It doesn't help that my rig is awkward in this mode, and my PC-control option has a problem I've yet to solve. Add, to this, my manual rotator-controller, and it adds-up to several uncompleted contacts. VO-52 is, of course, harder than ao-7 because of it's height/speed.
Considering just this reason by itself, HEO is much more inviting, because the doppler-effect is so greatly reduced. I think this reason might be shared by several other HAM's on the BB, even if they don't mention it. I even feel a little embarassed to admit that I haven't been able to cope with the different rates of doppler-shift for uplink and downlink. I might have to put my old transciever (FT-726R) back on the air, just because it was a lot easier to control both VFO's mid-QSO to keep centered. I don't even think I've completed one, since I've gotten my relatively modern "satellite rig" FT-847, despite several attempts to do-so.
Dear Auke,
It is very easy to get automatic doppler tuning working and I highly recommend it. Load up InstantTrack on any PC, even a DOS '386! and download InstantTune for free from the AMSAT web site here:
http://www.amsat.org/amsat/ftp/software/PC/radio-control/itune110.zip
Follow the instructions in the readme.txt file. It is very straightforward.
There is no reason to work linear satellites without automatic doppler tuning. You need the PC anyway to track the satellite - just hookup the COM cable it makes satellite QSOs simple.
VO-52 is very easy to work and is actually much easier than AO-07 since the downlink is so strong. You do not need to track the antennas - you can easily work it with omni-directional antennas. I have worked it with just an FT-817 running 5 watts into nothing more than a full wave loop a few feet above ground and another full wave loop for receiving. With an FT-847, it is a breeze.
I do not know why you are having trouble with your FT-847 auto-tuning but if you need help, send me an email.
73 (and don't give up on VO-52!) Tony AA2TX