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finally trying to wrap my head around EME — what does a realistic starter setup even look like

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so ive been lurking on the JT65 EME frequencies for a while now and honestly its kind of blowing my mind that people are bouncing signals off the moon and actually making contacts. i get the theory, i just cant quite figure out where the floor is in terms of equipment if you actually want to get on and work stations.

right now i have a pretty solid 2m setup — TS-2000 driving a SSPA putting out around 500w into a pair of 9el yagis, az/el rotator situation on the mast. i know the big guns are running 4x32el yagis or dish setups and like a kilowatt or more but i see mentions of guys doing EME with a single yagi which seems impossible to me honestly. is that actually happening or is that just the good stations working the little ones?

also the preamp situation confuses me — i know youre supposed to have a really low NF preamp right at the feedpoint but how much does that actually matter when your path loss is like 250dB? feels like youre fighting a losing battle either way. just trying to figure out if my current hardware gets me in the door at all or if i need to seriously upgrade before i even bother trying.

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your setup is actually not far off for getting started on digital EME. 500w and a pair of 9el yagis is going to give you maybe 15-16dBd of antenna gain which combined with a good low noise preamp puts you in the range where JT65B contacts are genuinely possible on random. you wont be working every station you hear but the bigger stations will be able to pull you out.

the preamp question is a real good one and yeah the path loss is brutal — something like 252dB on 2m — but the reason the preamp NF matters so much is because your receive noise floor is almost entirely set by that first stage. if you have a 0.3dB NF preamp right at the feedpoint versus even a 1.5dB NF preamp at the shack end of 20ft of coax, youre talking about several dB of system noise figure difference and on EME that is the difference between copying a signal and not. the moon isnt going anywhere but those fractions of dB really stack up.

single yagi EME is a thing but mostly that means the station on the other end is running a huge array or a dish and they can pull you out even if you cant really hear them well. its called an asymmetric contact and its totally legit for EME purposes. check out the ON4KST chat, a lot of stations post their schedules there and you can sked with someone who knows your signal will be weak.

the NF thing is not intuitive at all, i spent like two weeks confused about the same thing when i started poking around EME. basically think of it this way — the signal coming back from the moon is so far down in the noise that every tenth of a dB you can shave off your system noise figure is actually meaningful. i run a Lunar-Link preamp right at the feedpoint with like a 0.15dB NF and even that small improvement over my previous setup made a noticeable difference in what WSJT-X was decoding.

your 500w and dual yagi setup honestly sounds like a reasonable starting point. i made my first EME contact with similar power and a single 17el yagi, it took a while and i had to sked with patient operators but it happened. just get on the ON4KST logger and let people know your grid and your setup and youll find someone willing to work you.

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