Building my Eggbeater II Omni low Earth orbit satellite Antennas for 70cm I only had vertical 5/8 ground plane antenna fro 70cm and 2m band. M2 Antennas Eggbeater Satellite Antennas offers exciting new performance characteristics for both fixed and mobile operations and will let you. Constructing an egg beater antenna for working satellites is reasonably straight forward. George Wilenski’s (ON6WG / F5VIF) documentation.
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His prototype design, however, may be difficult for the average back yard mechanic a ham with two left thumbs to reproduce. But ko2f eggbeatet he made an STL for a drill template. I am currently unable to supply any more surplus cable, but you could contact Dino, K6RIX, to see if he can provide you with a small amount. Did you check your eggbeater antenna with an antenna analyzer?
[amsat-bb] Homebrew Up-Dated Eggbeater Antenna
FO was antdnna, FO was pretty workable but really crowded from Hi supercazzola, There are no plans, everything is done with pen and paper and the drilholes are just measured and pointed on a PVC tube. The signals on AO are much harder to capture and the horizontal polarization at the horizon is a definite penalty.
It is recommended reading. They are lightweight and can be carried out to the FD position, one in each hand. Yet also noticed that a few very strong stations on The first distinction is it does not use a round “loop” for the driven elements. Any hints or clear plans would be a help. As it happens I have a bunch of it I picked up 30 years ago that I have been salvaging the braded copper shield from for grounding straps.
Hi Bob, I did some testing with a rtl-sdr. Modeling showed me why the original eggbeater never had an SWR below about 1. For the 70 cm downlink, it could mean the difference between copy and no copy. The distance is not so critical and can be adjusted a small amount to get the SWR perfect. The loops will be 54 cm wide by Remember that 6 dB is gained in reduction of the satellite’s path loss and 3 dB is gained in the improved circularity of the signal as the bird reaches higher elevations.
The antennas are now moved to their fixed location and everything has to be reconnected again.
The rpi and the ftp cable have been ordered… Greetz, Joseph. Slip the guide on your pipe and align the line on the top of the guide with the mark on your pipe. If each loop has acceptable SWR near your desired frequency, the phasing line should make very little difference once they are combined.
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How is your testing going? Even without a fancy analyzer you can do a fairly low power check at several frequencies across the band, and see where is the lowest SWR.
Mark a straight line along the length of your pipe. To use it, Print the drill guide, scaling it to fit snugly over the plastic pipe you are using to make your antenna. Commercial versions are available from M2 Antennas. This 93 Ohm cable is not as commonly available as RG-8 or F. This placement helps “pull” the major lobes down to the horizon instead of “pushing” them overhead as in the original eggbeater design.
Print the drill guide, scaling it to fit snugly over the plastic pipe you are using to make your antenna. As phasing line between the two antenna loops I used 2 pieces of RG58 paralel. The antenna is linearly polarized horizontally at the horizon and the pattern becomes more and more right-hand-circularly-polarized RHCP as the elevation pattern increases. The “eggbeater” antenna is an omni-directional antenna employing circular polarization to maximize signal capture from low Earth orbit LEO satellites.
I am testing it in parallel with a commercially built Eggbeater manufactured by M2 Antenna Systems. Last week i also made a few eggbeaters one for MHz and one for MHz. Construction was easy and took about half a day.
It will do nothing. I have received good reports from several builders of this antenna.
They look the part. Since the two rectangle-loops are fed in-quadrature but out of phasethe resultant feedpoint is very close to 50 Ohms with no reactance.
As the pattern rises in elevation, it becomes more and more RHCP. With the reflectors installed, test for SWR. If there is any interest, I can probably write up a construction article and provide the STL file for my drill guide. I would be interested in learning more about this approach.
The reflectors will be cm long and cm distance from the feed point. In case you do not own one, than ask amateurs to help who have one. The RG will be 45 cm long plus 2.
I have these antennae built and stored in the garage. This antenna, mounted at 35′ elevation, performed very well for an omni-directional design. Best 73 Gary let me know how you make out. Starting with a square and “playing” with the shape allowed me to find a very good match at Ohms, purely resistive. I used the plans posted by k50e and am at a loss as to what is causing it.
At 5 degrees above the horizon, signals on FO start to come alive.
[amsat-bb] Homebrew Up-Dated Eggbeater Antenna
I find these to be very broadbanded and forgiving if your dimensions are even close. If you are using another metric perhaps pipe size, most 3d printers allow you to scale a part fggbeater too much difficulty. It has been my workhorse LEO antenna ever since, but of course, it is a directional antenna.