On Sun, Nov 29, 2009 at 8:02 PM, Michael Tondee <mat...@netcommander.com> wrote: > I've been trying to get my receive setup going the last few days but I'm > having horrible results. I have my 11 element 70cm "cheap yagi" back up > on the mast and my homebrew SaebrTrack and OR-360 AZ/EL TV rotator > system interfaced to SatPC32. > I have an ARR preamp mounted at the mast fed with a seperate 12VDC > feed and about a 40 foot run of JEFA brand LMR 400. Once I get into > the shack there is a bit of patchwork to the cables. I'm using a Yaesu > VX3 to receive and due to the SMA connector on the HT and not wanting to > strain it I have a 4 foot adapter cable of LMR 100 that goes from an > SMA to a SO-239. I then have to use a short length of coax with a PL-259 > to N male to mate up with a N barrel connector connected to my LMR 400 > coming from outside. Now obviously, I know this isn't optimum and eats > up valuable RF and I intend to change it ASAP but I'm hearing > absolutely nothing on AO-51 passes. Not even the hint of signals. > I'm thinking with that preamp in the line I should at lest hear > something discernible besides noise regardless of the patchwork of > cables. Am I off base in thinking this? I did catch just a bit of > discernible signal off SO-50 last night but it was almost overhead. > I'm not a beginner at this but I'm frustrated. Perhaps I'm putting too > much faith in the preamp to push the signals through my hodgepodge of > adapters and cables? Any thoughts are appreciated. > 73, > Michael, W4HIJ
Michael -- I think something is quite amiss here, perhaps a connector is bad or a bad joint in one of the cables. I bet a couple of hours with a volt-ohmmeter will find the guilty party. Alternatively, you could be in a bad noise situation. By way of comparison, because of my digital project right now I have a very minimal station, with a 70cm vertical antenna soldered directly onto a N-connector. About 10' of LMR400 goes to the preamp, which then has another 100' of cable to my FT-817. AO-51 is not great copy, but I know it is there. Similarly, all the usual cubesats in CW mode, and SEEDS (CO-66) with its fine FM signal of cheering Japanese school-children. (Actually, this got me thinking that SEEDS would make a pretty good way of evaluating two side-by-side receiving systems. Pass the resulting wav files through a SSTV decoder, and the one with the better picture wins!) You might consider making a very simple vertical antenna, attaching it to one end of the preamp with a very small patch cord between it and the radio, and using that as a kind of baseline. 73, Bruce -- http://ve9qrp.blogspot.com _______________________________________________ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
