ESP32 Based SDR Transmitter - Part 3 BPF, Preamp and fixing some Amp problems
This is the third video in the SDR transmitter series and in this video I move on to the bandpass filter after the Tayloe Encoder as well as building up a little preamp to raise the signal up to that required by the Amplifier. I don't get to installing the amplifier and LPF in this video but I do some troubleshooting with a broken QRP Labs 10W amplifier
Part 1 - • ESP32 Based SDR Transmitter - Part 1 Audio...
Part 2 - • ESP32 Based SDR Transmitter - Part 2 Taylo...
Preamp board
https://github.com/thaaraak/tayloe-pr...
BPF board
https://github.com/thaaraak/double-tu...
QRP-Labs 10W Amplifier
https://qrp-labs.com/linear.html
0:00 Intro
01:04 Bandpass Filter Schematic
02:07 BPF Board populated
03:23 BPF on the Spectrum Analyzer
04:06 BPF installed after the Tayloe Encoder on the oscilloscope with single tone
04:55 Comparison to signal without BPF
05:37 Comparison with two tone test
06:20 A view on the spectrum analyzer
08:27 The amplifier I will be using
09:21 Oh oh - I broke the amplifier! Some troubleshooting
11:05 IRF510s pulled from board
11:37 More blown components found
12:52 Amplifier back working again and testing the output on the scope
14:44 A quick look at the input impedance of the Amplifier using the minivna
15:50 Preamp schematic
16:36 Preamp board
17:09 Preamp board populated and testing out of circuit
18:24 Preamp installed after BPF and tested
21:39 Wrapup and next steps