"tom" wrote in message
...
On 2/25/2013 9:50 PM, Sal wrote:


Thanks. I've heard 6m is very good that way. I have 6m FM but not my
son-in-law ... yet. Besides, I haven't found any linking from Livermore
to
me in Southern CA.

See, Livermore has plenty of repeaters, both local and in three nearby
cities, Tracy, Pleasanton and Danville. Once you get beyond that region,
mountains become an issue and the nearest known linked repeaters are not
line-of-sight. I'm hoping some antenna gain will let me use edge
diffraction to make one of the machines. I'm hoping the first edge out
of
Livermore will do it. Yes, I have consulted terrain profiles.

Related: At Lowes today, I bought an 8-foot length of stiff, ribbed,
plastic channel called "lattice moulding" and it will be the boom for my
1.25m masterwork. It's very rigid in the vertical orientation, which is
what I want. If I have time, I'll rebuild the driven element with a
T-match.

"Sal"

So what you need is a design that will fit on an 8 foot boom. About 7
feet 11 and a half inches. I will see what might work well.

How much was the channel?

tom
K0TAR


"I will see what might work well." So, do you think the design from the
antenna book is less than ideal?

The channel is priced at $15.94. I will put some masking tape on my piece
of channel, mark off element positions from various designs, attach the
elements temporarily (tape) and evaluate the resulting antenna.

I will set up a makeshift antenna range, with (1) my tracking generator
feeding a 220 whip radiating from my lawn while (2) a helper in the driveway
aims the antenna and while (3) it send its receive signal into the shack
where I, aka His Royal Hamminess, notes the received signal at various
azimuths. (We don't need any stinkin' anechoic chambers.)

Professionally, I've made quantitative measurements of field strength ...
Singer NM-25, anyone? ... but I have nothing approaching modern precision
gear as that which rents for hundreds of dollars a week.

RELATED: If you know, why do some yagis designs place the first director
quite a bit closer to the DE than the rest of the directors' spacing? In
other yagi designs, the spacing of the directors is relatively consistent,
where DE-to-first-director is about equal to the spacing of the remaining
directors. I haven't seen that difference explained ... yet. Thanks.

"Sal"