Tuesday, June 2, 2009


Lyrid Meteor and Milky Way

I just received a note from Dave W9DR. I've met Dave a time or two at the Flex Booth at the Orlando Hamcation. He always fly's his colors wearing a Flex T shirt.

Here are some excerpts from his emails to me

Hi Lee, I really enjoy your SDR blog. I have an SDR-5000 and run meter scatter every morning on 6 meters when the band is NOT open. I use a FlexRadio SDR-5000, 7 element 31 foot yagi over another 7 element at 1/2 wave spacing. Using a W8IF HB Q-bar for phasing and 1/2" super flex coax from the watt meter in the shack to the driven elements on the yagis. HB 8877 Amp.

He said he would send a writeup and a couple of screen shots

The above shows two screen shots on a FlexRadio SDR-5000 panadapter on the 6 meter band.

The first is a screen shot showing the panadapter in "Peak" hold for about 30 seconds. In this mode, the signals shown are over a 92 KC band width on the 6 Meter beacon band. The signals are propagated to my QTH in SW Florida (EL86) by meteors (the band is not "open"). These meteors are not coming from a meteor shower, but rather random meteors that occur daily and are best seen right after sunrise. This takes place 365 days a year. My antennas are pointing north and the 'Peak" will show the highest signal above the noise, and is recording at 15 frames per second for the period I select (usually about 30 seconds). The beacon signal, as displayed by the panadapter, will be the highest (vertical peak) achieve during this period.

The second screen shot is a zoomed-in view of the panadapter, showing higher resolution view of the meteor scatter signals, and can even show doppler (signal frequency shift) or chirpy beacon signals. Most beacons seen are running 50 to 100 watts. Generally, beacons running 10 watts or under cannot be seen above the noise floor. Note the signal strength in 3 db steps, showing signal strength above the noise floor.

At the Dayton Hamvention 2009, a group of us 6 meter "nuts" set up a receiver in the flea market with an SDR-5000 and two stacked 4 element beams. We could see my beacon in SW Florida (915 miles) on the panadapter via random meteors in the flea market at Dayton, Ohio. The band was not open.

73, Dave, W9DR

This is another example of how incredible this technology is. I did a little meteor scatter back in the 70's when I lived in IL. The experience was nothing like this. In my day it was 1 minute transmissions alternating on even and odd minutes depending if you were the north or south end of the circuit or something like that. I'll have to look that up since I live in FL now virtually everything is north!!

Ain't Ham Radio just too cool? Bouncing signals off of stardust!! Thanks Dave for the writeup!