[Mobile-Portable] New car and considering new antenna setup!

[Art Clemons]

> As mentioned, some of the screw drivers are base loaded and some are low
> center loaded, none are top loaded.  The Comets and the Diamonds are top
> loaded which is the tremendous advantage.  A top loaded configuration works
> the best.

I don't know why you would think that a thin top loaded antenna would 
work better in a mobile environment, and in fact, the thin design to 
allow top loading if that's what the Comet's do, leads to less 
efficiency than centerloading.

Now a 6 inch diameter Bugcatcher which is mounted at the center will 
out-perform a screwdriver, but then again a top hat on a bugcatcher will 
usually out-perform just a bugcatcher.


>>Further, there have been 
>>numerous shootouts on 75 meters and 40 meters with the same output power 
>>comparing antennas like the Screwdriver and the Comet, the Comets lose 
>>every time.
> 
> 
> I haven't seen any reports of such shoot outs.  Though I suspect that an
> honest comparison would show that the low cost Comet and Diamond antennas
> to be a lot better than many would have otherwise thought!  


You haven't been on this list long enough, they've been posted several 
times.  You might also want to look at the September 1995 issue of 
WorldRadio for one sample.  You can also search google's back list for 
internet postings.  In fact, on this list, the results have been done 
several different times.


>>Anyone who has ever tried both on the same mobile will 
>>notice the difference quite readily.
> 
> 
> How one mounts the antenna has a lot to do with it.  Most screw driver
> installations are installed on the lower portion of the automobile, such as
> a tow bracket, or bumper, which is certainly not an optimum location.  A
> Comet or Diamond mounted at that position would certainly not work well,
> but if the Comet/Diamond is installed up higher which is usually possible
> with its low profile, then the results are quite spectacular.
> 

Actually, the only thing that might let a Comet/Diamond out-perform a 
screwdriver is mounting the bottom of the coil on a screwdriver below 
the roof of the mobile, and even then, I would be really shocked.  Just 
try the two on the same mobile for yourself.  When I add in the 
fragility and the like, it's an even worse choice.  Quite frankly, for 
about $170, one can buy a working W6AAQ screwdriver, and one can build 
one for even less, using plans that are readily available.  I can't see 
spending over $50 to build one if one can get some 2 in diameter 
Aluminum tubing of the proper length.