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.
|Published (Last):||28 March 2015|
|PDF File Size:||20.62 Mb|
|ePub File Size:||4.14 Mb|
|Price:||Free* [*Free Regsitration Required]|
I suggest a quick continuity test between the shield and center conductor of you coax and phasing lines before you start tearing your hair out. How often does a satellite go above 75 degrees? 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.
They look the part. If you sended an e-mail than your question should appear after an admin has allowed: FO was easy, FO was pretty workable but really crowded from Not very often; and the duration of it’s stay in that high elevation is very brief.
As a matter of fact it won’t tune at all. The antennas are now moved to their fixed location and everything has to be reconnected again.
ZR6AIC: Building my Eggbeater II Omni LEO Antennas
CGerald R. Jerry’s notes suggest first checking the SWR with the two loops in parallel, without the phasing line.
Did you check your eggbeater antenna with an antfnna analyzer? 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.
Select your Location
But ko2f said he made an STL for a drill template. I got good copy on the bird once it reached about degrees elevation–compared to to degrees on my original eggbeater. The ring lungs at one end of the phasing line can be shared with the 50 Ohm feedline F or equal recommended so that only four ring lungs are required. If you use the “original” eggbeater as the starting point, it is easy to describe this improved design, dubbed Eggbeater IIin terms eggbeatre differences and deviations.
I have been working on a uhf eggbeater antenna for about a week and cannot get the thing to tune worth squat. The idea of using 2 RG58 cable segments in parallel for the phasing line is new to me. Modeling showed me why the original eggbeater never had an SWR below about 1.
If each loop has acceptable SWR near your desired frequency, the phasing line should make very little difference once they are combined. I believe this increase is due to the improved circularity as the pattern rises.
Let us know how you make out direct email is OK too.
Home made Eggbeater antenna – Hardware – Libre Space Community
This implies an ideal omni-directional antenna would have an elevation pattern that was -6 dB from 30 degrees to 90 degrees–focusing the gain from the horizon up to 30 degrees elevation–where you need it the most–but without the deep overhead null presented by high-gain verticals. The TPM improved the coaxial gain of the eggbeater by re-shaping the loop into a square and moving the reflector closer to the driven eghbeater.
Hi Bob, I did some testing with a rtl-sdr. Nevertheless, how to improve the eggbeater as an omni-directional antenna?
I find these to be very broadbanded and forgiving if your dimensions are even close. Any hints or clear plans would be a help. I have received good reports from several builders of this antenna. The second major distinction is the location of the reflector elements.
[amsat-bb] Homebrew Up-Dated Eggbeater Antenna
Eggbeater Check for a short in your coax and phasing lines, It can happen to the best of us. Since the two rectangle-loops are fed in-quadrature but out of phasethe resultant feedpoint is very close to 50 Ohms with no reactance.
The distance is not abtenna critical and can be adjusted a small amount to get the SWR perfect. The garden-variety home-brew version employs a degree “phasing” line to provide a fixed right-hand circular polarization RHCP.
Instead, rectangles are formed. There are no plans, everything is done with pen and paper and the drilholes are just measured and pointed on a PVC tube. His prototype design, however, may be difficult for the average back yard mechanic a ham with two left thumbs to reproduce.
For the 70 cm downlink, it could mean the difference between copy and no copy.