[VHFcontesting] Antenna recommendations for Rovers

[James Duffey]

Dan - You wrote:

	I am looking for recommendations for antennas for Rovers.

I use the WA5VJB Cheap Yagis and have been very happy with them:

< http://www.wa5vjb.com/yagi-pdf/cheapyagi.pdf >

They are easy to make from readily available parts, have good  
performance, clean patterns, no fuss tuning, and are in fact cheap. I  
have made the 3, 4, and 6 element 2M versions and the 11 element 432  
Mhz version. They are good performers and hard to beat for the effort  
and cost expended.

For 6M, a Moxon is a good choice. It is easy to make and has good  
performance, although at 2 elements it is a bit short of gain.  On the  
other hand, it is compact and easy to handle and has a broad pattern,  
virtues among rover antennas. Here is N2MH's version, easy to make:

< http://www.n2mh.net/moxon.htm >

Again, it is easy to make from available parts and if built to the  
dimensions given is no tune. It is a big step up from a loop with  
little more effort or cost.

On my last rove, I used a loop patterned after:

< http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=16852 >

for use while the car is in motion. I substituted aluminum U channel,  
1/2" x 1/2" x 1/2", for the half inch copper tubing and fastened the  
ends together with self tapping screws. I added a fiberglass  
stiffening rod across the middle. This is more complicated to build,  
but still simple, and the parts can be had at your local hardware  
store or home supply warehouse. It is a bit tricky to tune, but if you  
have an antenna analyzer it is not hard. Performance is significantly  
down from a 2 element Yagi or Moxon and this is not a problem with  
sporadic E, but is for troposcatter contacts. If you mainly stop and  
setup rather than operate in motion, I would not use a loop. They are  
mediocre performers, particularly for loop to loop contacts.

The 6 ft boom of the WA5VJB Yagi is easy to handle and put up and  
down. I think one could go to 8 ft or 10 ft booms before it got clumsy  
and I am going in that direction. I have used a 15 ft boom Yagi on 2M  
when it was the only antenna on the mast, and that was doable for a  
sprint, but I am sure in a full weekend contest I would smash it into  
somehting else and with other antennas on the mast, it might be  
difficult to handle.

I am also considering longer 432 MHz antennas but pointing becomes  
difficult. Stacking might be the answer, but then that complicates  
things.

As you can see, I am a big advocate of building your own antennas and  
keeping them simple. Let us know what you choose to do. - Duffey
--
KK6MC
James Duffey
Cedar Crest NM