Rate this post by selecting a number. 1 is the worst and 5 is the best.

Author Message   holl_ands Advanced Member Username: Holl_ands Post Number: 339 Registered: 06-2004 Rating: N/A Votes: 0 Posted on Monday, March 14, 2005 - 03:17 am:    KGTV-DT & KSWB-DT: DTV PROPAGATION PREDICTION PROGRAM (PPP No. 3) ANTENNAWEB.ORG says I need yellow antenna for KNSB-DT and KPBS-DT, a red antenna for KSWB-DT and violet for KUSI-DT. And no other DTV stations....but most people believe that it is overly conservative. I also found that the prediction was the same for me at the bottom of the 60 foot hill and my neighbors at the top...so go figure... I'm still hoping that some enterprising Linux expert is interested enough to download SPLAT! (free) and do some charts for SD stations.... In the mean time, I ran across RADIO MOBILE, a FREE VHF_UHF PPP that (also) embeds the Irregular Terrain Model: http://www.cplus.org/rmw/english1.html It has lots of capability, nearly as much as the expensive commercial products. Which means, of course, that it requires some CommSysEng knowledge and lots and lots of patience... A few examples follow, but first some landmarks: Mt Soledad is "big" hill on the coast with Mission Bay below (and Pt Loma in #3). I8 runs along the river channel at south end of Mission Bay. I'm located West of I15, just south of Camino Del Norte and a few miles north of Rt56 (that's the big canyon. That big lump of RED is caused by the shadow of Black Mtn. First image shows how Black Mtn blocks signals coming from Mt Soledad, even though I'm only 14 miles away. I don't even get multi-megawatt CH 8 and 10. Also note how lots of other nearby areas have blockage. Mt Soledad is a terrible location for a TV transmitter. Second image shows the calculations for KGTV-DT reception from Mt Soledad....looks marginal. Third image is twice the scale of the first and shows how well KSWB-DT covers San Diego, and blockages in mostly distant valleys. So I guess, theoretically, all of the SD DTV stations can be received at my location with at least a 10 dB Fade Margin. It also says I can receive most LA stations with same or better Fade Margin. Right now I'm rather skeptical about Radio Mobile results....it may be too optimistic. Perhaps others can correlate their on-air performance to the predictions.... KGTV-DT Signal Levels: KGTV-DT to holl_ands Path Calculation: KSWB-DT Signal Levels: (Message edited by holl_ands on March 15, 2005)