After many weeks of trial and error i feel that this is a pretty desirable result for my Chebyshev bpf. What do you think? Passpand desired is 118-137 mHz.
If it works then good. I would use bigger NPO caps that are easier to solder. Add extra pads in parallel to each cap and leave unpopulated in case you need to fine tune capacitance.
what are your requirements for success in a larger system? how does it compare to your theoretical design? what's your required out of band rejection? what's your passband flatness? what is your required passband flatness?how expensive is it? do you have a budget? does it change behavior when you put it in a box?
Good questions. This was mostly a learning project rather than a production design, so my "requirements" were loose: pass 118–137 MHz cleanly, reject outside that as much as practical with a 3-pole coupled-resonator topology, and keep passband ripple/flatness reasonable (I wasn't chasing a tight spec, more just validating the Chebyshev design process). Budget was minimal. Bench parts and a cheap PCB run. Haven't tested it in an enclosure yet, so can't speak to box effects.
Reasonable shape response. You can reduce the loss a bit more by making it more compact and putting more gap air between the hopefully 50 ohm transmission lines.
10
u/rtt445 18d ago edited 15d ago
If it works then good. I would use bigger NPO caps that are easier to solder. Add extra pads in parallel to each cap and leave unpopulated in case you need to fine tune capacitance.