I got a total of 30 private emails and a few that showed up on the
reflector- wow! Thanks to everyone-
Here is the results of the finished project:
I installed 24 buried radials, 20-70 feet long in a 360 degree fashion. I
think the average worked out to be about 40 feet per radial- The SWR without
radials was 1:1 and had a usable 2.5:1 bandwidth was 70Khz centered at 1.820
using my MFJ 259B analyzer. The RF was certainly waking up the ground worms-
With radials, my SWR went up to 2.1:1 at resonance point of 1.818Mhz. I
used an Amidon UnUn to match the 50 ohm RG213 coax (50 foot run) to the
antenna impedance of what, 36 ohms? Messing around, I found a combination
that gave me an SWR of 1.3:1, fb! Now, with an ok radial field, my usable
2.5:1 bandwidth shrunk down a lot to just 25Khz- So I am at 2.5:1Mhz at
1.835, 1.3:1 SWR at my most resonant point of at 1.818Mhz, and 2.5:1 at
1.810MHz- The band edges really go fast up past these points- But the Pro
III tuner can tune about a 40KHz 2.5:1 band width but struggles much past
this point- So basically, I can go from 1.800-1.850Mhz with the tuner.
The most significant change in SWR came when I added the last 6 radials. I
went from 1.3:1 with 18 radials to 2.1:1 with 24 radials. The last 6 were
mostly 50 feet in length. I only had to fold back 2 of the entire radials
due to space.
Performance wise, this morning I worked a very small station, VE5LF, 900
miles from here, who was only running 100w and a DX Engineering 43 foot
vertical with a long wire added and tuned to the top band. His report to me
was 599 and he emailed me to say he was surprised I was only running 100
watts and a MA160V as I sounded very loud- This was a significant contact
for us because with the Alpha Delta sloper, we had typically only made
contacts with big guns over 500 miles who were using excellent RX antennas,
at least from station descriptions at QRZ.COM.
Unfortunately, I spoke to Dick at hizantenna systems in OR and I can not use
any rx array he makes due to the proximity of the antenna to the array
field. It has to be at least 200 feet away or the array will be
significantly messed up and I can blow out my rx circuit on the Pro III,
which I used to do at my WY contest QTH off the beverages- ughh- So now I am
looking for another solution for rx. But the MA160V, even with S-7-9 noise,
hears very well- I heard EU's during CQWWSSB and Africa and worked VP9 and
VE2 this week- I also worked VE1 during CQWWSSB with only half of the
current radials- this is a huge improvement off of the Alpha Delta Sloper-
I know I got at least 18 referrals to hizantenna systems from my first Low
Band post- - all fb- too bad my lot is not big enough- Any suggestions on
alternatives for a decent rx antenna that could work are appreciated. For
alternative rx antennas, I listen right now mostly with the 8 ele LPDA just
by switching from ant 1 to ant 2 on the pro III- it seems to hear the best
out of what I have hear at the farm- but even still, the MA160 still pulls
out all the weak ones-
So to conclude things, I feel this is a great antenna for a small lot. I
don't see this antenna acting only like a screw driver antenna in the back
yard- I understand how models are important, but reality wise, this antenna
acts a lot better than what some of the models I have seen posted claims it
will- it has a real punch stateside and coast to coast in VE and I know it
will work EU and KH6 this season with 100W. Now, if I can just improve my
160 rx with less noise, I'll be ok- but for now- things are fine with the
antenna as is- I know that there are a limited supply of these now since the
new owner of Cushcraft is not tooled up to make anymore yet- maybe soon I
hope- - Many of the big stores like HRO are back ordered and I only found
mine at AES and they only have a few from the old Cushcraft left-
Thx for all the tips- I used many of the suggestions received- I'll be
putting a picture of the feed point on my qrz.com site later today-
73 Paul N0AH
-----Original Message-----
From: Mark Lunday
Sent: Thursday, November 04, 2010 7:29 AM
To: '(N0AH) Bryon "Paul" Veal' ; topband@contesting.com
Subject: RE: Topband: Cushcraft MA160 Vertical questions
PS Your QRZ.com page...wow, nice 4-square setup on 80 at your old QTH.
Must have been heartbreaking to leave that behind.
Mark Lunday
WD4ELG
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
|