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SUN Noise



Ladies and gents:
Seeking some info.  Finally managed to make crude, but repeatable
sun-noise measurement on my ao-40 S-band rcv setup.

Set up below:

2ft dish ==>DEM .7dbnf preamp==>2ft 9913==>Drake downconverter==>50ft
RG-6Quad sheld==>variable attenuator==>DEM 144-28==>IC-751 (agc
off)==>HP RMS voltmeter

I get about 0.5 to 1db sunnoise, either by using attenuator to match
voltmeter or simply reading the voltmeter scale.

Question:  Is this a reasonable number?  
Qualitatively, I hear the bird fine, tho not the noise floor.

Have used the spreadsheet from SETI for G/T, but it wants flux in
Janskys, and th sources of flux data they point to provides flux in
unknown units (or at least I didn't see it anywhere.)  Making a guess
about the units on one site maybe being Janskys, I get a spreadsheet
value of G/T of 0.3.  

Question:  IS this a reasonable number?  What are you guys with better
AO-40 S-band receive setups seeing?

All comments, suggestions, enlightenment appreciated.

73,
Jim
wb4gcs@amsat.org

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