Great empirical info, Eddie.
Can you say something qualitative about your ground conditions ? For
example, "irrigated soil", "rocky hilltop", "sand", etc.
You are doing something right - Huge signal on topband, and you also
hear very well.
73,
Steve, N2IC
On 09/20/2013 06:31 AM, Eduardo Araujo wrote:
Hi friends,
I finished sending the measurements data to all that requested it.
In case somebody didn´t receive it yet, please let me know.
Even though I did not mention it before, I also have Field Strength measurement
synchronized in time with the AIM measurements.
As surely this was not a professional procedure, I will explain how I did it
and you may judge if it is useful for you or not.
- I installed 2 verticals antennas 3 mts long, at about 300-350 meters from the
tower base in two opposite directions. So measurement was done at ground level.
- I did not tuned up the elements in any way, they were connected to the FS
instrument directly and as ground connection I used a 50 cm aluminum pipe
buried in the ground
- As a FS meter I used a DIGI - FIELD from IC- Engineering
- First 2 radials were installed more or less in the direction of the RX
verticals
- From there, they were installed consecutive in counter-clock wise. (look from
above)
- I used 20W at 1840 during daylight, and matched the antenna input for every
change in radial number. I used an MFJ-962B for this purpose.
- After all readings were done, I calibrate the readings against an HP-8640B
signal to visualize which was the change in db
Botton line - the measured change at ground level between 2 and 114 radials was
between 5.2 in one direction and 5.8 db to the other.
I understand this is not a professional procedure nor professional equipment
and it was done having fun enjoying the hobby.
I will like to hear from you your thought about if this kind of measurement
done at ground level and at that distance from the antenna base has a
correlation to actual radiated Field at the maximum vertical azimuth of the
vertical whichever it is.
And, also, How the procedure or elements I used could be improved ....still
within amateur measurement accuracy and not professional level.
'73 to all..... Eddie, LU2DKT
----------------------------------------------------------------------------------------------------------------
From: Eduardo Araujo<er_araujo@yahoo.com>
To: Topband<topband@contesting.com>
Sent: Thursday, September 12, 2013 9:28 AM
Subject: Measuring Vertical input parameters while installing radials
Hi everyone, I recently complete the installation of +100 1/4 radials for the
1/4 vertical.
I measured input vertical parameters using AIM4170 from 1600 to 2000Kc
I assumed it is not something new for many of you, but I wonder if the
information I collected may be of interest for some of the group members.
I have available for sharing BMP or JPG images of each scan which were run at 2, 4,
8, 16, 32, 60 and +110 radials. Also, I have the .scn files for each scan which
could be viewed using AIM4170 SW even though you don´t have the unit.
The good thing looking at the files using the sw is that you can move the
cursor and have all the values at all fcies from 1600-2000 Kc
In case someone is interested, let me know and I will see the way to share it.
´73 to everyone.... Eddie, LU2DKT
PS: By the way, what a nice toy the AIM !!!, Even though I bought it more than
one year ago, this is the first time I use it
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Topband Reflector
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Topband Reflector
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