[VHFcontesting] 6 meter antenna heights (LONG )

[Gregg Seidl]

Very interesting reading!In 2006 I installed a pair of M2 6M-7JHV's 
controlled by a Comtek stack match box.I have one at 62 feet and one at 38 
feet.It is VERY interesting to be able to switch between the two during an 
opening and record the which antenna does what and at what 
distance,propagation mode and my general "feeling" of how the band is.I've 
been writing this down during most non-contest openings that I've been on 
the air for.
    My findings are as such; for short what I call no opening QSO's or more 
likely ground wave under 200 miles the higher antenna is ALWAYS 
better.....by a bunch.Sometimes the other station is NOT even readable on 
the lower antenna.
    For what I call the "skip zone" meaning 200-400 miles where E skip could 
happen but doesn't normally support those distances unless the Sporadic E 
cloud is very strong and 2 might be open,its 60-40 to the top antenna.From 
my records and seat of the pants,I've noted that it seems to be related to 
if the opening is just starting or if it is ending.It also seems to be area 
related too.If the opening is toward W4 it's more like 40-60 with the bottom 
antenna being better.If its toward AZ,NM,CO and that area it even more 
tilted toward the top antenna.I haven't been able to REALLY determine if 
that is just because of my normal operating time,which is about the same all 
the time or if it really is related to area.
    For true E skip in that 400-1000 miles,BOTH are nearly always better.I 
think there is really no such thing as signal fading,rather I think that the 
angle of arrival is merely changing.Because most antennas have a null in 
their vertical pattern as well as horizontal pattern we think of it as 
fading.With 2 antennas one can "cover" all angles better.I have noticed a 
drop in faded signals running 2 antennas as opposed to 1 antenna.It really 
doesn't seem to matter area or time of day or whether the opening is 
starting or finishing,both are 90% better then either one.The other 8% the 
lower one is better but that is only for the closer in stuff,more like 
400-500 miles.I can't figure that one out.Anyone got any ideas??
    Past 1000-1200 miles is REALLY weird.Sometimes both are better,sometimes 
bottom is better and sometimes top.I haven't been ablemake enough QSO's to 
REALLY understand that one.From EN64ck there isn't a lot of stations for me 
to work so my records are fairly empty at that range.Just when I think I've 
been able to think I know which one will be best,it throws me a curve ball 
and my idea gets all messed up!I really wish I could work 100-200 stations 
at that distance during the course of an E-skip season.Not going to happen 
though!!
    1200 miles and farther the top is 95% better.If the DX is coming in I 
just switch to the top antenna.There is no need to switch between the 
2.Again my QSO numbers are limited at that range.
    I plan on recording this info for several years and then publish it 
somewhere so everyone can see.

I may change the heights this year however,I have found that for DX 62 feet 
is not high enough.I might move them to another tower.They would be 38 feet 
and 85 feet.I have also thought about going to a 3 stack at 38,62 and 85 
feet.If I would do that my data would still be valid and I could add more 
data about the distances that the higher antenna is better.Plus I could add 
which 2 are better because the Array Solutuions box allows yoou to select 
which 2 you want.
    To that note,if you hear me working an E-skip opening and I'm asking the 
other station where they are,as in which city please understand that.I know 
I'm in kind of a rare grid square and I'm trying to work everyone but I 
enjoy doing this research.Just hang tight and hopefully I'll work you too 
and be able to your callsign to my data.I have over a 1000 in my data 
now,not all different callsigns but different times.

    My station consists of an Icom IC-7800 to an Icom IC-PW1 amp running 
1000 watts into 70 feet of 7/8th's Heliax to the Comtek Stack-Match box.27 
feet of LMR-600UF conect the stack box to the antennas.The bottom antenna is 
mounted on an IIX "swinging gate" that turns from 300 degrees thru 0 degrees 
to 175 or so degrees.The top turns every way.I have nothing in the path of 
the antennas.The antennas again are 6M-7JHV's.

    If anyone has an Array Solutions 3 stack box made for 6 meters that they 
no longer need please let me know.Same for a NIB 6M-7JHV antenna. Thanks for 
reading my ramblings,I thought someone might be interested in this.Comments 
always welcome......Gregg K9KL