Why does my oberservation look so different?

So I’m just now getting my v3.1 rotator up and going. So why does my observation look like this - https://network.satnogs.org/observations/159243/ compared to https://network.satnogs.org/observations/158569/

Right now, I’m not using a LNA or anything, just a UHF eggbeater

Let’s look at the obvious differences between observations 159243 and 158569
Same satellite - CUTE-1

  1. Both RTL-SDR have been calibrated, the background noise on 159243 is higher than 158569.
  2. 159243 - 28 degree max elev. pass, 158569 - 77 degree max elev. pass.
  3. 159243 - configuration: Egg-beater—RTL-SDR–RPI?
    158569 ??? ----> ???

–Konrad, WA4OSH

Also the one on station 6 has the WIP CW flowchart it seems or something. Your waterfall is so nosiey because of a problem in the current flowchart for CW so I suggest trying to compare another type of observation.

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Two new observations:
https://network.satnogs.org/observations/159245/
https://network.satnogs.org/observations/159112/

Same satellite 30776 - FALCONSAT 3
Background noise similar
Max elev. similar
Mode FSK9k6 same
Frequency 435.103 same

https://network.satnogs.org/stations/16/
https://network.satnogs.org/stations/89/

Height above ground – are you really at 175m at your QTH?
This sets your minimum horizon far lower

Antennas slightly different, similar performance
UHF Turnstile vs UHF Eggbeater

I still think it’s something with your antenna. Let’s check that one out when I get home ~4:30 pm PST
I will catch you on chat.

–Konrad

You may have to turn your RF Gain up higher. Mine is at 43.3 for my vertical antenna. (Not very sat friendly I know :frowning: )

Yours is only 12.5 and you said you don’t have an LNA. (Neither do I)

In my satnogs client I think I put 2m, it’s not clear if they want elevation above sea level, or rotator elevation from ground. Also I believe you have to put elevation in your station info on the website, should I be using above sea level or above ground?

How do you compensate for noise floor on the waterfall? If I turn gain up, won’t the noise floor wash the waterfall out?

Antenna height over average terrain.

–konrad

I don’t really get that much more noise.

Increasing the gain decreases the amplifier noise figure which increases SNR.

–Konrad

Please use height above sea level (ASL) for your stations!
“Apomahon” is running an older version of satnogs-client - sure one before the CW decoder’s waterfall broke.

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I just talked to @fredy who said that “Apomahon” uses latest client since last UTC-night :wink:

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Then we need to clarify that in the instructions. Here in Seattle, it’s almost the same thing :wink: and the unit is meters or localized to metric/SAE? I will fix the Wiki tonight.

Question … So in Colorado, I used to live at 10,000 ft / ~3200 Meters but just north of a 14,000 ft mountain ? How do you calculate the lowest elevation?

–Konrad

When did it change to above sea level?

Last time I did stuff with my station it was above the ground.

@KD9KCK it was always above sea level :slight_smile:

The reason we need this height/elevation is that we use it for calculation of the passes. We use pyephem for it and as you can find in its documentation (search for sea in the link):

elevation — Height above sea level (m)

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Fredy,
You may need to change the guiding text to “Height above Sea Level in meters”

This is what led me to give bad advice above.
–Konrad

Same here and on IRC it was said as that too when I was getting my station back up.

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But I took Fredy’s advice and looked at the Python code … it’s looking at elevation from sea level. He’s right.

I’m on IRC chat #satnogs now

–Konrad

Does your antenna work with your SDR?

To test my SDR, I’m running gqrx on my Linux laptop. But, you should be able to do the same thing on any program to drive your RTL-SDR. I “kerchunked” my local 36/96 repeater (input is 146.36 MHz). The third harmonic is 439.08 MHz. The RTL-SDR can pick it up with no problem.

–Konrad

I have changed description in the wiki and I’m going to change it also in network.

If you find another location that should be changed please let me know or feel free to fix it if you are able too :slight_smile:

Thanks!

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