Radio Campo

W6CAW /W6SLW

NVIS Antenna for Mobile Link

Motorhome Mobile

Mobile Radios and Antennas

Well, after wining a Icom IC-7000 at the 2008 DX Convention I figured I better get it installed. I have been running a Yaesu FT-8900 for years but no HF in the mobile. After using a mag mount since I purchased my 2007 Sport Trac I was ready to drill some holes in the roof. ( Actually, a professional installer friend of mine W6NXS drilled the actual holes and installed the mounts and I did the rest.)


Above the dash torn up to bring power to the GPS and code light, and the control cable to the 8900.

Finished dash. The GPS and control head for the 8900 are mounted to the rear of the
front code light. Before I pulled the dash apart I had cables hanging down the side of the
dash. My prize 7000 control head, is stuck to the console with a home made 45 degree
bracket.


The cookie sheet mounting system is my biggest pride and joy. Power distribution, the "boxes"
for the 8900 and 7000 and a LDG AT-7000 tuner are bolted to a cookie sheet. The whole thing
slides under the back seat. I came up with this idea as when you fold down the back seat it lowers
itself and would crush the radios so, when I lower the seat I slide the pan to this forward position.
When the seat is upright the pan slides under to the position shown below.

Another advantage to my pan is, all the antenna connectors are easy to get at. If I want to setup
one of my external beam antennas or a long wire during a field day or emergency operation
it's real easy to connect the feedlines. Also it's easy to get to the programming and data connections.
Someday I will figure out how to use my SignaLink USB TNC?

The roof.
Front center a 6M/2M/70Cm for the 8900.
Left rear is connected to the 2M/70Cm output of the 7000.
Rear center HF ball mount for the HF side of the 7000. Currently using HamSticks.
Right rear. The do everything mount. goes to a loose cable in the cab. Normally has an 800Mhz
antenna hooked to a Motorola 5000 series portable, San Diego County, RCS fire radio. By changing
the antenna I can hookup my AM aircraft transceiver or any number of scanners or fire or ham portables.
The glass mount on the drivers side is a cell antenna for my Verizon phone or wireless card.


The finished product, ready for fun or fire season.

NVIS Antenna for Mobile

Some of the best ideas are "borrowed" from the internet. The Near Vertical Incident Skywave (NVIS) antenna is designed to put maximum signal straight up. The result is near communications, 30 to 300 miles, on HF frequencies, primarily 80 and 40 meters. An excellent discussion on NVIS can be found at http://www.athensarc.org/nvis.asp. checkout the many reference links at the bottom of their page. Also, if you really want to fill an afternoon Google NVIS Antenna.

The project I built came from http://emcomm.org/projects/nvis.htm As I looked at their setup I realized all I needed to do to duplicate it was take one of my spare quick disconnects and bolt 60 feet of antenna wire to it with a 3/8 24 bolt screwed into the quick disconnect. Just push and turn to attack it to the ball mount, string the other end of the wire to something 4 or 5 feet off the ground and you have an 80 Meter NVIS antenna. I have tried it once to good effect. More testing coming. Not bad for an antenna and dacron attachment line that fits flat into a 1 quart zip lock bag. PS. Turns out great minds think alike, mine is just slower. While Googleing I found this link on eham http://www.eham.net/articles/4141 Stephen T. Reynolds W4CNG built what I just figured out in 2002!

Motorhome Mobile Mobile

When going mobile in the Motorhome I take the Yaesu FT-897 and set it on top of the dashboard, operation at rest only. More photos to follow.

Above my portable 80 Meter antenna for motorhoming. When not motorhoming I put in the back of my truck and use it for portable emergency communications. I have since replaced the mast with an MFJ-1910 33' fiberglass push up mast. I don't use the top 2 sections as they won't support the weight of even my 24 gage 80 meter (about 120') dipole. This puts the mast at 27' which is about 5' higher than the old mast in the photo. ( made from 4ea, 5' nesting TV masts.) Looking around the internet, and comments from other operators, I think I may upgrade to the MGS masts.

The base of the mast is held in place with an RV flagpole mount I got at the SD County Fair. It fits under the front tire and has a tube the mast fits into. I use PVC pipe sections to match the diamater of the mount to the smaller size of the mast.

Links

W5JGV large home brew mobile antenna


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