September 2002 WV Expedition

SUCCESS!!!

Many more contacts!!! At least for W3GCW.

A lot of time was spent building the 'wire beam' (see QST, Nov. 2001). It didn't work as well as the wire loop, but it was a great learning experience. The control of being able to flip the antenna from directing south to directing north was really surprising.

Camp was smaller than the June Expedition. One end of the beam (seen here with a blue rope tied to it) was attached to a guyed mast made from heavy gauge conduit. The mast was topped with an Arrow antenna for VHF/UHF.

 The wires to the right of the Arrow are the wire beam reflectors. The three parallel wires to the left are the driven elements for 10m, 15m, and 20m. The top of the mast is about 36 feet above ground.

On our way off the mountain, we stopped to make some VHF contest contacts from Bear Rocks. Near constant rain on Sunday provided for a wet camp tear-down. If you look closely you can see a faint rainbow to the right of the trees.


About the Equipment:

This trip we used an IC-706mkII and an FT-817. The IC-706mkII station was powered by an 80AH gel-cell battery. The radiator was the wire beam. Rig control and PSK-31 was provided by an IBM ThinkPad 600X laptop. Logging was performed manually as W3GCW doesn't always trust the hard disks to make it home in one piece.

A 24AH gel-cell battery powered the FT-817 which excited the 77' Delta Loop antenna. An IBM ThinkPad T21 laptop performed the logging and PSK-31 functions for N3MK.

A standard car 'emergency backup' battery was used to charge the two laptops. Voltage direct from the 12v battery wasn't enough to charge the laptops. A power inverter was used to create AC that was turned back into DC by a standard 'AC adapter' for the laptop. This provided the 16v necessary for the laptops to charge. In the future, a DC-to-DC converter should probably be used to minimize the inefficiency and loss of valuable power.

Where Did We Go Wrong With the Wire Beam?:

We aren't sure, but we have our ideas. The wire beam is not easy to build without a HUGE flat surface lay it out. If you are planning to build this, do so in the comfort of your backyard, driveway, or non-busy street. Also, it takes a great deal of alignment and probably even more work to tune right. Getting the reflectors centered with the driven elements was near impossible with our supports leaning against trees and our wires getting hooked on indigenous shrubbery. Also, construction took much longer than expected (almost 6 hours total). By the time we had it together, we needed to get it up and get on the air! So that's what we did. With the 100 watt IC-706mkII, contacts with Europe required some repeated words, but were not impossible. Most likely, the next trip we will only use the 77' Delta Loop antennas.

Different For the Next Trip:

As mentioned above, Delta Loop antennas for each of us. The Delta Loop we use has the horizontal side on the bottom and is center fed with ladder line running straight from the antenna tuner. The loop is made from 77 feet of chandelier wire and strung from the highest tree we can find. On this trip, we attached the upper apex to one of the guy ropes for the main antenna mast. For more information on the Delta Loop, check out W4RNL's 'Notes on All-Band Use of  Vertical-Plane Deltas' and 'Part 2: The Delta Branch.'

The 80AH battery, we project, could run the IC-706mkII for several days with normal use. It could run the FT-817 even longer. Next trip will probably include two 80AH batteries. But just in case they get a little low, we will have the solar panel charger on hand, as well as a gasoline powered battery charger from an old camper.

And the most important addition will be receive filters. And lots of them. Our current setup is close and comfy, but doesn't allow us both to operate at the same time. Especially our favorite weak signal mode, PSK-31. Even the FT-817 will crush other receivers on other bands when the antennas are only 50 feet apart. Our first filters will be the W3LPL type.

Our main shelter, the orange fly seen in the first picture above, will be upgraded to include more poles and a better installation. With some practice, we hope to be able to put it up in the dark when we get to the site, instead of in the morning on the second day.

If we can get a few of these kinks worked out, we should be able to get on the air the evening we arrive, instead of the next morning. This should provide us with an extra 5 to 7 hours of operating time. Good emergency operations should never be limited by the dark of night, and neither should the fun trips. We'll see you next time...

de W3GCW



Well, it's back to the mountain top! Yea!!

4000 feet: nothing even 1 degree above the horizon in any direction. Perfect RF view, all directions.

We'll probably be a little more conservative with the radios this time. Mostly to conserve power. On the flip side, we should be more prepared with more power than before.

Antennas may improve this time. We expect to take the usual N3MK Delta Loop and wire dipoles, but new to the kit is a Wire Beam (see QST, Nov. 2001).

The date:

September 14, 2002 00:00Z to September 15, 2002 20:00Z.

The Operators:

Support Staff:

Radios:

Antennas:

Processors:

Power:

Modes: