APT preamps

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srcejon
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APT preamps

Post by srcejon »

Here's a comparison of a couple of preamps I have for APT.

Here's the S21 plot for the Uputronics 137.5MHz NOAA/APT Filtered Preamp

Uputronics_NOAA_S21.PNG
Uputronics_NOAA_S21.PNG (49.87 KiB) Viewed 5 times

And for the Nooelec Sawbird+ NOAA

SawbirdPlus_NOAA_S21.PNG
SawbirdPlus_NOAA_S21.PNG (46.07 KiB) Viewed 5 times

I measured a NF of around 1 dB for both.
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