DIY transceiver: Crystal ladder filter

This is an introduction to electronic filters and part of DIY HAM radio Maker-Blog of HB9GZE witch you find here: https://hb9gze.ch

This series covers in diffrent videos:
1. Introduction to electronic filters:    • Introduction to electronic fiilters  
2. Designing an analog bandpassfilter :    • DIY transceiver: bandpass & lowpass f...  
3. Designing a crystal filter:    • DIY transceiver: Crystal ladder filter  
4. Do some experiments with active filters:    • Active filter experiments  
5. Setting up a digital IIR filter on a STM32F4:    • Digital filter experiments on STM32F4  

see also:
1. Introduction of DIY homebrew HF transceiver,    • Introduction to DIY HAM radio transce...  
2. Antenna amplifier,    • DIY transceiver: Antenna amplifier  
3. Bandpass filters,    • DIY transceiver: bandpass & lowpass f...  
4. RF mixer,    • RF mixers  
5. Crystal filter,    • DIY transceiver: Crystal ladder filter  
6. Preamplifier,    • Preamplifier design and test  
7. Power-amplifier,    • HF Power-Amplifier MRF101  
8. CPU, still open to do...

Pls. find documentation, schematics and code on www.hb9gze.ch.
There you also fin all the links to the tools I used.
Find the code of the digital filter here: https://github.com/HB9GZE/Pub_STM32_A...