Author Topic: LM didn't have enough power.  (Read 1226 times)

Offline JayUtah

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Re: LM didn't have enough power.
« Reply #30 on: February 13, 2019, 09:26:46 AM »
Atmospheric absorption, especially by water, becomes significant at higher microwave frequencies.

A problem we encountered routinely in the theater when using water-based fog products in combination with custom RC-controlled equipment.  We'd lose just enough signal to drop the lock occasionally.
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Offline bknight

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Re: LM didn't have enough power.
« Reply #31 on: February 13, 2019, 10:04:27 AM »
I love this forum, as I learn so much.  Although I do suffer from CRS at times.  :-[
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Offline ka9q

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Re: LM didn't have enough power.
« Reply #32 on: February 14, 2019, 09:19:50 AM »
Atmospheric absorption, especially by water, becomes significant at higher microwave frequencies.

A problem we encountered routinely in the theater when using water-based fog products in combination with custom RC-controlled equipment.  We'd lose just enough signal to drop the lock occasionally.
Really? That would definitely surprise me, unless the equipment was getting waterlogged.

I was referring to absorption by heavy rainstorms, which becomes significant above 5-10 GHz on satellite downlinks that don't have a lot of margin to begin with.

Offline JayUtah

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Re: LM didn't have enough power.
« Reply #33 on: February 14, 2019, 01:16:56 PM »
Really? That would definitely surprise me, unless the equipment was getting waterlogged.

I was referring to absorption by heavy rainstorms, which becomes significant above 5-10 GHz on satellite downlinks that don't have a lot of margin to begin with.

Yes, this was custom, in-house-built equipment somewhere in the S-band range that didn't have a lot of margin with the transmitter and the receiver sitting next to each other on the desk.  I didn't build it, so I don't know all the details.  But I had to operate it in the fog, and swore quite a bit in the process.
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Offline apollo16uvc

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Re: LM didn't have enough power.
« Reply #34 on: February 14, 2019, 02:28:06 PM »
Weren't there some intermittent video recorded during LRV traverses? Like when the high gain antenna got close enough to the right direction to connect?
Yes. It looks like video when you finagle around with a pair of rabbit ears to try and get the TV signal to look its best in a snow storm, but there is video. My Google-fu seems to be failing however.
 Most of the stuff taken with the LRV in motion is with the 16MM DAC though.
This is the only one I know of, a few seconds of video;

AS 17 MET: 169:56:29
CC: Okay. We've observed something there. Stand by.   
Website link: http://apollo17.org?t=169:56:29
YT link: 
=26194
Would love to see more if they exist.
« Last Edit: February 14, 2019, 02:38:29 PM by apollo16uvc »
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Offline bknight

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Re: LM didn't have enough power.
« Reply #35 on: February 14, 2019, 04:34:27 PM »
If you are referring to the video as Gene is driving, then that is the only one I'm aware.  Video breaking up a little as the dish bounces from a "perfect" aim.
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Offline Allan F

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Re: LM didn't have enough power.
« Reply #36 on: February 14, 2019, 08:52:36 PM »
Weren't there some intermittent video recorded during LRV traverses? Like when the high gain antenna got close enough to the right direction to connect?

Would love to see more if they exist.
That is exactly the clip I remembered from 10-15 years back.
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Offline onebigmonkey

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Re: LM didn't have enough power.
« Reply #37 on: February 15, 2019, 03:04:01 AM »
If you are referring to the video as Gene is driving, then that is the only one I'm aware.  Video breaking up a little as the dish bounces from a "perfect" aim.

That clip was very useful when pointing out to a certain Welshman that there was evidence of them driving to the VIP spot :)

Offline bknight

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Re: LM didn't have enough power.
« Reply #38 on: February 15, 2019, 12:29:40 PM »
If you are referring to the video as Gene is driving, then that is the only one I'm aware.  Video breaking up a little as the dish bounces from a "perfect" aim.

That clip was very useful when pointing out to a certain Welshman that there was evidence of them driving to the VIP spot :)

Our boy hunchbacked indicated in one of his videos that the dish wasn't position properly.  Also he pointed out that this video had no abnormalities.  I inserted a comment that he should post the whole video not just his cherry pick portion.
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Offline nomuse

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Re: LM didn't have enough power.
« Reply #39 on: February 15, 2019, 08:48:05 PM »
Atmospheric absorption, especially by water, becomes significant at higher microwave frequencies.

A problem we encountered routinely in the theater when using water-based fog products in combination with custom RC-controlled equipment.  We'd lose just enough signal to drop the lock occasionally.

Plus there's all those water-filled bags jumping around the stage that the choreographer insists are necessary to the show.