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vhfwxsatellitetips-hw [2021/08/02 23:54] – [Radios] - added content mm3iigvhfwxsatellitetips-hw [2021/08/14 23:43] (current) – [Low Noise Amplifiers] mm3iig
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 +[[vhfwxsatellitetips|Front Page]] | [[vhfwxsatellitetips-antenna|Antennas]] | [[vhfwxsatellitetips-hw|Hardware]] | [[vhfsatellite-sw|Software]] | [[vhfsatellite-general|General Tips]] | [[vhfsatellite-gallery|Gallery]]
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 ====== Hardware Overview ====== ====== Hardware Overview ======
  
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 And finally remember: you can’t do this with a handheld and out to an audio jack as the 25 kHz bandwidth won’t be wide enough for even APT. MM3IIG tried it, and got a discernible image but without all of the required information for enhancements and using the full sensor data. And finally remember: you can’t do this with a handheld and out to an audio jack as the 25 kHz bandwidth won’t be wide enough for even APT. MM3IIG tried it, and got a discernible image but without all of the required information for enhancements and using the full sensor data.
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 ===== Low Noise Amplifiers ===== ===== Low Noise Amplifiers =====
  
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 If you move away from VHF to higher bandwidth/frequency signals later on then you’ll definitely need to look into one, (as well as bandpass filters appropriate for the band) and don’t forget they’ll need power (through whatever method required). Check the current draw and that your power method or SDR can actually provide enough. If you move away from VHF to higher bandwidth/frequency signals later on then you’ll definitely need to look into one, (as well as bandpass filters appropriate for the band) and don’t forget they’ll need power (through whatever method required). Check the current draw and that your power method or SDR can actually provide enough.
  
 +The Nooelec stuff is all great and well-supported, and if you're feeling lucky there are suppliers on AliExpress who do clones of the combined LNA/BPF boards. Remember to check how you'll power the LNA (USB or Bias-T) and that you have enough current to do it.
 ===== Bandpass Filters ===== ===== Bandpass Filters =====
  
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 This also applies to those weaker signals at lower angles (for both APT and LRPT). Sometimes you’ll want the gain up to help and that lets the intermod in. Filtering before gaining up will mean your radios front end won’t have as many issues with other signals interfering. This also applies to those weaker signals at lower angles (for both APT and LRPT). Sometimes you’ll want the gain up to help and that lets the intermod in. Filtering before gaining up will mean your radios front end won’t have as many issues with other signals interfering.
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 +Here's a good resource on making a filter with the kind of materials you may have lying around (standard capacitor values, etc): https://lucasteske.dev/2016/11/137mhz-bandpass-filter-for-noaa-meteor-satellites/
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 +You may well decide that a certain signal is so powerful that you want to use a notch filter to remove it instead, of course.
vhfwxsatellitetips-hw.1627948478.txt.gz · Last modified: 2021/08/02 23:54 by mm3iig