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Groups > sci.physics.relativity > #461689
| Newsgroups | sci.physics.relativity |
|---|---|
| Date | 2018-06-18 21:11 -0700 |
| References | <561aded2-0656-4233-92d9-06b3e0618017@googlegroups.com> <af33e704-e5d5-4de3-9bef-d232f81e812f@googlegroups.com> |
| Message-ID | <a13db689-282e-49dc-bc87-62bc8530a92f@googlegroups.com> (permalink) |
| Subject | Re: Apollo 11 |
| From | Steve BH <sbharris@gmail.com> |
On Monday, June 18, 2018 at 2:53:34 PM UTC-7, numbernu...@gmail.com wrote:
> Calculate it yourself. The SEFD is how much signal doubles detector temp.. It is intensity per degree in Janskys (Jy). One Jy is 10^-26 J/m^2/Hz..
>
> ________________________________________________
>
>
> What is the sensitivity for a 2 Ghz radio signal? Also, what is the power of a 2 Ghz mobile phone. Say 3 miles from the radio telescope?
It's better to say how much better a radiotelesope dish is from a simple dipole detector on a cell tower.
The biggest dish used during Apollo 11 was the 210 foot military dish in the US, which NASA used during landing. Which was good because for some seconds the rotation of the LM during landing lost them their directional antenna lock (from the LM-- this is a hand cranked device at the edge of the LM with a gain of 20 dB = factor of 100, but it has to be pointed at Earth) and in the gaps they were operating on one 15 watt S-band omnidirectional transmitter on the LM picked up by a 210 foot dish on the ground. The frequency was 1.3 GHz. Had they lost telemetry altogether they would have had to abort the landing, and the 85 foot dishes were not up the job when the LM high gain went out.
1.3 GHz is 23 cm = 0.75 feet.
Large antenna gain = {4pi[210 feet/0.75]}^2 times antenna factor (usually about 0.5) = 6.2 x 10^6 = 68 dB
You get further distance from the LM tranmitter working nominally at 15 watts RF output vs. a mobile phone at only 3 watts max. So 10 log [15/3] = 7 dB.
Okay, the total you get from the big dish and LM bigger transmitter is 68 + 7 dB = 75 dB. Are you paying attention? This increases your distance of pickup by 6 dB per doubling of distance, or 2^[75/6] = 58,000.
So there you are. If you can get a link with your cell phone 5 miles from your cell tower, the extra factor of 58,000 in distance from a big dish and a bit more power gets you all the way to the Moon.
If you want to read about the actually com system for the Apollo program you can do it:
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720012253.pdf
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720023255.pdf
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Apollo 11 numbernumber1964@gmail.com - 2018-06-04 15:44 -0700
Re: Apollo 11 Vaughn Fleck <guah@nhnw.nc> - 2018-06-04 23:09 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-04 19:58 -0700
Re: Apollo 11 intuitionist1@gmail.com - 2018-06-06 08:26 -0700
Re: Apollo 11 Zandra Sobczak <acako@raswa.bo> - 2018-06-06 16:03 +0000
Re: Apollo 11 dlzc <dlzc1@cox.net> - 2018-06-06 09:13 -0700
Re: Apollo 11 Zandra Sobczak <acako@raswa.bo> - 2018-06-06 17:05 +0000
Re: Apollo 11 intuitionist1@gmail.com - 2018-06-06 11:53 -0700
Re: Apollo 11 Zandra Sobczak <acako@raswa.bo> - 2018-06-06 20:09 +0000
Re: Apollo 11 intuitionist1@gmail.com - 2018-06-07 06:06 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-07 07:35 -0700
Re: Apollo 11 intuitionist1@gmail.com - 2018-06-08 05:56 -0700
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-08 12:53 -0700
Re: Apollo 11 intuitionist1@gmail.com - 2018-06-09 15:36 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-07 10:12 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-07 17:39 +0000
Re: Apollo 11 Volney <volney@volney.invalid> - 2018-06-07 13:40 -0400
Re: Apollo 11 Paparios <mrios@ing.puc.cl> - 2018-06-07 10:46 -0700
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-07 13:29 -0700
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-07 13:23 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-08 08:36 -0700
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-08 12:56 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-07 12:17 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-07 20:57 +0000
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-07 12:19 -0700
Re: Apollo 11 Volney <volney@volney.invalid> - 2018-06-07 15:47 -0400
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-07 12:22 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-07 12:51 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-07 12:54 -0700
Re: Apollo 11 Paparios <mrios@ing.puc.cl> - 2018-06-07 14:47 -0700
Re: Apollo 11 Zandra Sobczak <acako@raswa.bo> - 2018-06-08 17:03 +0000
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-08 09:40 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-08 09:41 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-08 17:00 +0000
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-08 09:45 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-08 22:06 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-08 10:37 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-08 17:48 +0000
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-08 12:59 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-08 12:29 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-08 20:54 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-08 22:14 -0700
Re: Apollo 11 Zandra Sobczak <acako@raswa.bo> - 2018-06-09 15:10 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-10 22:15 -0700
Re: Apollo 11 Zandra Sobczak <acako@raswa.bo> - 2018-06-12 18:38 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-16 16:33 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-16 21:33 -0700
Re: Apollo 11 Werner Ballard <db@ocoak.bn> - 2018-06-17 11:36 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-17 10:29 -0700
Re: Apollo 11 John Gogo <jfgogo22@yahoo.com> - 2018-06-20 18:08 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-08 12:29 -0700
Re: Apollo 11 Paparios <mrios@ing.puc.cl> - 2018-06-08 15:26 -0700
Re: Apollo 11 Zandra Sobczak <acako@raswa.bo> - 2018-06-09 15:13 +0000
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-10 17:26 -0700
Re: Apollo 11 Paparios <mrios@ing.puc.cl> - 2018-06-10 17:41 -0700
Re: Apollo 11 Zandra Sobczak <acako@raswa.bo> - 2018-06-12 18:50 +0000
Re: Apollo 11 Zandra Sobczak <acako@raswa.bo> - 2018-06-12 18:48 +0000
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-13 09:27 -0700
Re: Apollo 11 Pasquale Broman <lqs@basq.ce> - 2018-06-13 20:36 +0000
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-11 09:21 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-11 16:36 +0000
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-11 09:23 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-11 09:25 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-11 16:36 +0000
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-11 09:27 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-11 09:34 -0700
Re: Apollo 11 Paparios <mrios@ing.puc.cl> - 2018-06-11 10:37 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-11 09:40 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-11 16:56 +0000
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-11 09:42 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-11 16:56 +0000
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-11 12:23 -0700
Re: Apollo 11 Paparios <mrios@ing.puc.cl> - 2018-06-11 14:45 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-11 12:25 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-11 19:57 +0000
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-11 12:50 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-11 12:51 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-11 12:55 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-11 13:29 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-11 20:45 +0000
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-11 13:36 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-11 20:49 +0000
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-11 14:31 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-11 15:00 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-12 09:35 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-12 09:36 -0700
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-13 09:17 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-13 19:47 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-12 09:37 -0700
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-13 09:19 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-12 13:50 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-12 22:06 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-12 15:45 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-12 15:29 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-12 23:21 +0000
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-12 15:55 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-12 15:58 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-12 17:09 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-12 17:12 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-13 00:50 +0000
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-13 09:31 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-12 17:15 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-12 17:20 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-12 19:03 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-12 18:17 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-12 20:17 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-13 11:02 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-13 20:07 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-13 11:03 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-13 11:05 -0700
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-14 07:02 -0700
Re: Apollo 11 Werner Ballard <db@ocowak.br> - 2018-06-14 15:58 +0000
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-14 11:01 -0700
Re: Apollo 11 Werner Ballard <db@ocoak.bn> - 2018-06-14 21:10 +0000
Re: Apollo 11 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-06-14 23:39 +0200
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-15 08:48 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-13 13:44 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-14 11:19 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-14 16:55 -0700
Re: Apollo 11 Tom Roberts <tjroberts137@sbcglobal.net> - 2018-06-14 19:21 -0500
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-14 17:31 -0700
Re: Apollo 11 Tom Roberts <tjroberts137@sbcglobal.net> - 2018-06-15 11:58 -0500
Re: Apollo 11 Paparios <mrios@ing.puc.cl> - 2018-06-14 18:23 -0700
Re: Apollo 11 Volney <volney@volney.invalid> - 2018-06-14 22:48 -0400
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-14 22:23 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-14 22:25 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-14 11:22 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-14 11:29 -0700
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-15 08:45 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-14 13:36 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-14 15:45 -0700
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-15 08:50 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-14 17:13 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-14 17:46 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-14 17:21 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-14 17:28 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-15 11:24 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-15 12:42 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-15 13:26 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-15 12:54 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-15 13:21 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-15 13:29 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-15 13:36 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-15 14:30 -0700
Re: Apollo 11 Werner Ballard <db@ocoak.bn> - 2018-06-16 14:51 +0000
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-18 14:53 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-18 21:11 -0700
Re: Apollo 11 Zprávn Udoucih <zpnvn@nwinst.ce> - 2018-06-19 17:55 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-19 16:25 -0700
Re: Apollo 11 Zprávn Udoucih <zpnvn@nwinst.ce> - 2018-06-20 10:37 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-20 15:33 -0700
Re: Apollo 11 Oren Woodcock <uw@osiweoq.lp> - 2018-06-29 23:04 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-29 20:26 -0700
Re: Apollo 11 Oren Woodcock <uw@osiweoq.lp> - 2018-06-30 13:08 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-30 18:33 -0700
Re: Apollo 11 Volney <volney@volney.invalid> - 2018-06-30 22:00 -0400
Re: Apollo 11 Oren Woodcock <uw@osiweoq.lp> - 2018-07-01 10:57 +0000
Re: Apollo 11 Oren Woodcock <uw@osiweoq.lp> - 2018-07-01 11:00 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-20 20:39 -0700
Re: Apollo 11 Oren Woodcock <uw@woswiw.lw> - 2018-06-27 10:51 +0000
Re: Apollo 11 Edward Prochak <edprochak@gmail.com> - 2018-06-27 11:35 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-27 14:18 -0700
Re: Apollo 11 Oren Woodcock <uw@woswiw.lw> - 2018-06-28 09:09 +0000
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-18 15:05 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-18 21:12 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-19 14:17 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-19 22:44 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-19 16:29 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-19 16:37 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-19 19:39 -0700
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-19 15:53 -0700
Re: Apollo 11 Odd Bodkin <bodkinodd@gmail.com> - 2018-06-19 23:21 +0000
Re: Apollo 11 furthermore7990662@gmail.com - 2018-06-19 15:58 -0700
Re: Apollo 11 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-06-20 07:31 +0200
Re: Apollo 11 Tom Roberts <tjroberts137@sbcglobal.net> - 2018-06-20 09:31 -0500
Re: Apollo 11 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-06-20 19:21 +0200
Re: Apollo 11 Zprávn Udoucih <zpnvn@nwinst.ce> - 2018-06-20 18:37 +0000
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-20 15:35 -0700
Re: Apollo 11 carleto4157990662@gmail.com - 2018-06-19 16:47 -0700
Re: Apollo 11 carleto4157990662@gmail.com - 2018-06-19 16:50 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-19 19:42 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-20 08:57 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-20 15:40 -0700
Re: Apollo 11 numbernumber1964@gmail.com - 2018-06-21 09:48 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-21 13:21 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-22 06:08 -0700
Re: Apollo 11 Steve BH <sbharris@gmail.com> - 2018-06-22 16:12 -0700
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