Topband: Measuring Vertical input parameters while installing radials

[Eduardo Araujo]

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





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From: Eduardo Araujo <er_araujo at yahoo.com>

To: Topband <topband at 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