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I don't have time to pencil it out, but it sure won't happen with their antennas and power levels.? ??

Quick estimating re:analogy to EME.? We have come a long way with earth to moon bounces.? ?I listened to?a?voice qso between two?earth?stations bouncing off the moon (well a recording).? A live image has been sent.? The EME record, with dish antenna 26 meters in diameter, transmitter in Europe, receiver in Australia, extremely sensitive receivers, is 3 mW for a decodable?data signal.? ?Round trip Pluto is about 17 hours,?ignoring doppler shifts,?polarization?scatter, tracking so?a receiver is pointing in the right place at the right time 17 hours later for a given slow pulse sequence ...? ?Now, the intensity of radio waves over distance obeys the inverse-square law, and pluto is 12,000 times farther away than the moon, ... so 12,000 squared = 144 million? which means, if we could replicate the enormous infrastructure for the 3 mW record, we would need 144 million * 3 mW = 432 kWatts.? ?A second data point is, amateurs with top end digital processing gear can EME on 100 W with a single fancy yagi .... so with that inexpensive level of equipment, we would need:? 14.4 gigawatts.??

It ain't gonna to happen.? And it really ain't gonna happen on HF.

?

On Thu, Jun 18, 2020 at 4:35 PM jim_kf7e@... <jim_kf7e@...> wrote:

??? These 'beams' are all HF below 50 MHz;,. (almost) all Amateur EME is done at 50 MHz and (much) higher frequencies.

??? Project Diana (circa 1946-47) originally used 111 MHz, several KW, and the planar array antenna had over 20 dB gain to generate (and hear) the moon echo.

??? I'm not sure about Planet X. It may require Plan 9 from Outer Space.

KF7E

On 18-Jun-20 14:43, Joe Sammartino wrote:

I think he means with RF but that is not the issue.

Look at the beam products offered - there's the clue.

On Thu, Jun 18, 2020 at 2:38 PM Dennis Lawrence <kf7ryx@...> wrote:

I do not think we can bounce our “voice” off the moon but rather an RF signal.

Dennis

KF7RYX

?

From: [email protected] [mailto:[email protected]] On Behalf Of Joe Sammartino
Sent: Thursday, June 18, 2020 1:59 PM
To: [email protected]
Subject: [QueenCreekHams] Beam Antennas

?

So who can figure out the problem with this email advertisement from Justin at MFJ Enterprises?

Every correct answer gets a prize.

Joe, N2QOJ

?

---------- Forwarded message ---------
From: Justin <mfj@...>
Date: Mon, Jun 15, 2020 at 12:32 PM
Subject: Beam Antennas

?

If you've got the space the best possible antenna for you is the beam with monster arrays made for DXing.

Beam Me Up Scotty! ? ? ? Is space really the final frontier?? Or can we take it further than that? Hams can bounce their voice off of the moon, how about Mars or Pluto or even Planet X?? Let's take our ham radio communications to the next biggest level.? How? You get a giant beam with a huge array capable of talking further and mightier than ever before.? Can we get there? You will never know until you try . . . ? ? ? Hy-gain Eleven and Seven Element Beams Cushcraft and Hy-gain have the beam antennas you need to get out!? Folks are always spending their big money on their radios and their amplifiers when the real effort is there with an efficient antenna system.? That is where the beam antenna comes in. If you've got the room, a beam antenna? gives you the best bang for the buck.? And really? the little bit of money it costs is money well spent.? Check out these awesome antennas! Check out the TH-7DX.? 7-elements, 1.5 kW PEP. 10-15-20 Meters. Gives you the highest average gain of any Hy-Gain tri-bander!? Average 8.7 dBi gain with just a 9.4 square foot wind area.? The boom is 24 feet long, the longest element is 31 feet.? it weighs 75 lbs. It's big brother is the TH-11DX. 11-elements. 1.5 kW PEP. 10-12-15-17-20 Meters. The choice of top DX-ers. ? ? ? Cushcraft Four and Three Element Beams A-4S is a four element beam for 10/15/20 Meters. An add-on kit gets you 40 Meters also.? The longest element is 32.9 feet with a 18 foot boom.? It sports a great 8.9 dBi gain with a 25 dB front-to-back. A-3S is a three element beam for 10/15/20 Meters. An add-on kit gets you 40 Meters also. The longest element is 27.75 feet with a 14 foot boom.? Get 8 dB gain with a 25 dB front-to-back. ? ? ? ? So you don't have a lot of space for a BIG beam? ? Let's talk about small compact beams then. Cushcraft's MA-6B gives you six bands (20/17/15/12/10/6 Meters with a bantam-size beam capable of up to 5.3 dBi gain!? The boom is just 7.3 feet and the longest element is just 17 feet. Or check out the MA-5B, its predecessor for just 10/15/20 Meters. Saves over $200 if you don't need 6/12/17 Meters. Hy-gain's TH3-JRS is a healthy contender!? 3-elements on 10/15/20 Meters.? It has an average gain of 8 dBi and a 25 dB front-to-back.? Just a 12 foot boom and a longest element of 27 feet. Tooled manufacturing gives you long lasting Hy-Gain durability. Weighs just 21 lbs. so a lightweight tower or roof tripod can be used. ? S ? ?