APT preamps
Posted: Tue Jan 24, 2023 4:37 pm
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
And for the Nooelec Sawbird+ NOAA
I measured a NF of around 1 dB for both.
Here's the S21 plot for the Uputronics 137.5MHz NOAA/APT Filtered Preamp
- Uputronics_NOAA_S21.PNG (49.87 KiB) Viewed 138 times
And for the Nooelec Sawbird+ NOAA
- SawbirdPlus_NOAA_S21.PNG (46.07 KiB) Viewed 138 times
I measured a NF of around 1 dB for both.