In a message dated 3/10/2007 12:25:04 A.M. Greenwich Standard Time,
john@kk9a.com writes:
I was just reading the 3830 results from last weekend's contest and I saw an
interesting comment by 6Y1V / KY1V.
http://lists.contesting.com/archives//html/3830/2007-03/msg00551.html The
6Y1V station has stacked SteppIR MonstIR antennas and on a separate tower
stacked monobanders for 10m, 15m and 20m. The monobanders were 2 to 3 S
units stronger than the SteppIRs.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Check the quote from the site:
The rotating tower supports 6 M2 Inc. long boom mono band yagis. On 20
meters we have 6/6 on 59' booms at 100' and 50'. On 15 meters we have 6/6 on
44'
booms at 65' and 32'. On 10 meters we have 7/7 on 44' booms at 55' and 28'.
The MonstIRs are something like 135 over 70.
The spacing is beautiful for 40 meters, but for 20 meters using 32 foot
booms that spacing is way is too great. The problem is compounded on 15 and
10.
It's no surprise the SteppIRs were pounded by the monobanders.
In Florida I used 5/5 at the same spacing for 20, 6/6 at the same spacing
for 15, and 6/6 at the same spacing that the 6Y guys are using. The stacks
kicked butt.
The three things working against the SteppIRs here are:
1. Less than optimal spacing...too great for 20 with the boom length and
especially 15 and 10 to generate much gain
2. Probably too high for stateside. The angles generated by the SteppIRs
would be way too high for east coast and much of the west side (6Y is not that
far from FL, and those heights rarely worked east of the Mississippi from
K4XS)
3. The monobanders are going to develop more gain all things being equal,
because of boom length.
What we have here is the problem I am facing in designing the stacked
SteppIR system...picking the compromise height. The thing missing in the 6Y
SteppIR stack is the ability to fill in the "hole" between 135 and 70 and
between
70 and ground level. If that was done we might have a closer horse race.
I'll put my money on a four high stack of SteppIRs at 135/100/70 and 35 for
20/15 and 10. That's close to what I am going to do at KH6.
Mine is still a work in progress until I get the OK from the building
department since the tower will be anywhere up to 150 feet of Rohn 55. Until
then
I will keep doing terrain analysis courtesy of N6BV.
By the way, I'd like to hear (off the reflector) from other guys who have
used SteppIRs in stacks.
Bill K4XS/KH7XS
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