Once again, I was in the single operator portable category with my tower trailer set up near the town of Madera (north of Fresno in California's central valley).  And once again, the Southern California Contest Club rovers really contributed to my score. 

     This time there were six rovers, K6FGV, N6HB (with K9JK), N6VI, W6TE, W6TTF, and WA6WTF.  They eventually activated 10 grid squares, starting at the Madera four-grid convergence, near my fixed site in CM96.  They activated CM96, CM97, DM07 and DM06, in that order.  I worked the rovers in each of those grid squares on 11 bands (six meters through 24 GHz), then followed their progress as they went to Kettleman City for grids DM05 and CM95.  I was able to work them there on 10 bands (everything through 10 GHz).  Then they continued south to Wheeler Ridge (just barely into DM04, but still in the central valley), driving slowly and cautiously in very thick fog.  The fog made their driving hazardous, but it also produced outstanding tropo ducting up the valley.  Over a distance of 149.6 miles from Madera to Wheeler Ridge, signals on the microwave bands were astonishingly loud.

     I've often said that the key to success in the single operator portable category is having microwave-equipped rovers within range, and it was certainly true this time.  On the lower bands, running QRP doesn't exactly give you a killer signal, especially when you're operating in the flatlands, not on a hilltop.  Using a tower trailer does help.  But on the microwave bands 10 watts seems like high power.  It certainly did during this contest, with the excellent tropo the length of the central valley.

     I was very happy with the results of this contest, although there were more than the usual hardware problems.  The most serious one for me was that my Yaesu G-2800 rotator froze, and did so at a heading that would have made it impossible to land and nest the tower for travel.  Fortunately, it happened during daylight and while the SCCC rovers were still nearby.  I lowered the tower from full height to its minimum height of 12 feet.  Jim Curio, K6FGV, and other rovers literally forced the rotator to turn.  It was a little scary, but it worked.  The rotator never froze up again.

     I was more than a little concerned about the prospects of another failure in the early hours Sunday morning.  I finished working the rovers at Wheeler Ridge about 3 a.m.  I was alone about five miles from town in the middle of nowhere.  It was very dark and extremely foggy.  Visibility was maybe 50 feet.  Everything was soaking wet.  As I started to shut down and lower the tower to drive away, I wondered if the rotator would work.  Would the electric winches that lower the tower and tilt it over for travel work when they were so wet?  Would I even be able to see well enough to get back on the highway?  Above all, what was a guy who has been licensed for 58 years and is, um, not  young, doing out there at 3 a.m.?

     Well, everything worked as it should, fog and water notwithstanding.  I drove away and found my way back to my hotel at 4 a.m.  On Sunday, the fog burned off, the sun came out and I went back out there to operate again.  It all turned out okay.  The tropo was about as good as anything I've ever seen up and down the central valley.  The microwave part of the contest was really exciting with those tropo-enhanced signals.

     Meanwhile, the SCCC rovers had wrapped up their own operating after 3 a.m. Sunday.  Some stayed in a motel at Wheeler Ridge but others drove back to L.A., arriving at home around 5 a.m.  After a few hours of sleep (too few), the rovers were back at it, activating grids DM14, DM03 and DM13.  There were lots of equipment failures for the rovers as well as me, but I think everyone agrees that it was a memorable contest.

*****(postscript)*****

     In response to a query, here's a postscript about the "tule fog" and "valley tropo."  Yes, they often go together, but not always.  Both end quickly when you leave the central valley and climb up into the mountains (on Interstate 5, for instance). 

     Is it possible to get into the valley tropo from above?  Yes, it often is.  My beacon on 144.293 MHz is located at 6,800 feet elevation in the Tehachapi Mountains, overlooking the central valley.  That is well above the top of the valley tropo layer, but the beacon is regularly heard the length of the valley.  When the valley tropo is good, it can be very loud.  K6MYC (of M2 fame) said during the contest that N6NB/B had been "pinning out" at his location about 150 miles north of the beacon site.  That's far stronger than normal.

     What about working out of the valley tropo and over the mountains?  That is possible as well, but there's likely to be far more signal attenuation.  In the eastern and midwestern states, tropo often enhances paths of 1,000 miles or more.  In the arid southwest, that's almost unheard of.  Not only is the weather usually too dry for long-haul overland tropo, but high mountains invariably interrupt any tropo that might develop.  The longest flat, low-elevation path with sufficient moisture we have is up the central valley.  Paths over multiple mountain ranges and across the desert seem limited to a few hundred miles, at most. 

     The only truly long-haul tropo we often see on the west coast is the duct to Hawaii--an over-water path.  There is another possible long-haul path--from Southern California down the curving Pacific Coast to points up to 1,000 miles away in Baja California.  That over-water path has been worked on 10 GHz--when someone was in the right place in Baja with the right equipment.  The record on that path was set with a combination of the over-water tropo and knife-edge propagation over a mountain range.  However, that path has not been worked in recent years because DXpeditions to sites deep in Baja have ceased to happen for security reasons.

***** (end of postscript)*****