.: Weak Signal Presentation, February 2015

Thursday, February 5, 2015

Weak Signal Presentation, February 2015

We were very fortunate to have Buddy Morgan deliver an outstanding presentation on Weak Signal Propagation. Buddy’s presentation has been added to our Yahoo Groups site and can be downloaded from there. Alternately, you can get a copy by clicking on the following link.

https://drive.google.com/file/d/0Bw3TCAlI9DPLZFFuQXNNbTBYMk0/view?usp=sharing

Most of us came to the meeting thinking that there was little more to 2 meters and 70 cm other than repeaters and Simplex. Those who attended, now know better. This is an area that needs some exploration. In addition to Buddy's excellent presentation, here are some links that you might find helpful:

Florida Weak Signal Society website http://flwss.net/

Your Grid Square Locator calculator http://www.levinecentral.com/ham/grid_square.php

For those who want to give a listen:

Weekly FLWSS SSB Net

432.090MHz SSB Net every Thursday evening at 8:30pm EST, Rotating NCS Monthly

East Coast 70cm Net every Wed. 9pm 432.090 W4DEX NCS

Cool formula to remember- Line of sight

Buddy covered many topics, but this is one we all can appreciate, the formula for determining the line of sight distance between two antennas, given you can find the height above sea level for each. Google Earth can be of great help here.

Theory is fine, but does it work? Let’s see. Peggy makes the Thursday Net easily from her home outside of Tampa which I happen to know from a good source is 37.17 miles from our repeater. Her antenna is is 23 feet tall, but you have to take into account the elevation of the ground at her home which is 37 feet above sea level. That puts her antenna at 60’ relative to sea level. The Lakeland Repeater’s antenna is 350 feet above sea level. OK, lets do the math.

d1 = 1.41 * SQRT 60 = 10.80 miles

d2 = 1.41 * SQRT 350 = 26.38 miles

Total distance = 10.8 +26.38 or 37.18 miles! Excellent agreement with the formula!

So download the slideshow and have some fun with something that has been there all along, but for most of us, unnoticed.