[Laser] Results from the Lunar Eclipse

[Jim Moss]

All,
I spent the early morning hours with my 8" scope & Hamamatsu H957-08 Red Enhanced PMT connected up to my PC running Spectran.
Being here in San Jose metro area, the local light levels are not great.  But the visual observation of the eclips was fantastic.  Watched as the earth's shaddow slowly covered the moon starting top left working its way to full coverage.  The red/orange glow was quite significant.  I took a number of handheld digital SLR pictures.

From the PMT setup, I had significant 60 Hz & harmonics visible in the open sky with no moon and no filters.
I added a YELLOW filter (often used for moon viewing) in order to narrow the bandwidth.  It is not very sharp, but provides some improvement.

When moving the scope & PMT to the moon in full eclipse, the light from the moon gave 20dB or more increase in overall noise.  The only discernable signals on Spectran with fairly short integration were from 60, 120, 155Hz.  The 60 and 120 were the same level as off the moon, so I don't think they are moon sourced.  The 155Hz also was something in my area, but not sure what.  I have a few 100's of MB's of WAV files if someone has some ideas on processing.

I created a strange way of displaying my results in this video at UTUBE.
http://www.youtube.com/watch?v=2mmQShcY-h8

Pictures are at 
http://new.photos.yahoo.com/n9jim@pacbell.net
Look in LUNAR ECLIPSE album

Jim
N9JIM



----- Original Message ----
From: Art <KY1K at verizon.net>
To: lee at aps-technology.com; Free Space LASER Communications <laser at mailman.qth.net>
Sent: Wednesday, August 29, 2007 10:09:18 AM
Subject: Re: [Laser] Results from the Lunar Eclipse


Lee and Kerry,

You might ask on the Spectrum Lab mailing list, some of those guys 
know the software and the algorithm(s) pretty well.

Also, many softrock users and other SDR related users have Edirol 
FA-66 and Delta 44 24 bit sound cards, which are very high 
performance (low noise inputs plus full 24 bit resolution. The FA-66 
comes with it's own power supply and runs outboard from the computer, 
so the interference from having the soundcard inside the computer is 
absent. If your work shows and trace of the 50 Hz artifacts, simply 
having one of the high end soundcard users run the same data might 
give you more definitive data.

The SDR people are very much into eliminating ground loop noise, by 
isolating the input and output of the soundcards with 
trasnformers-when you get down to 24 bit resolution, the interference 
created by these ground loops is not trivial!

I wonder if you used any of these high end soundcards to do the recording?

Regards,

Art

>Kerry, N6IZW and I, KD0IF, along with Jerry Petrizze, W6VLF, spent a
>beautiful night in the high desert east of San Diego observing the lunar
>eclipse and capturing many giga-bytes of .wav files.

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