Debugging of LC Bandpass Filters
 

Hi all,
In the past many people on the board have help me solve some
related problems. Thanks to all.


I want to know what is the procedure to find the problem with a
fabricated and assembled board. I have two kinds of filters on my
board
1) Coupled resonator filter of 4 order (differential). I have
simulated the circuit in spice and checked the waveforms at all
points. They do not match. May be because of parasitics. (inductor SRF
is large) or may some other reason I dont know of. I am observing
through a single ended cable.
2) LC butterworth/cheby filter BPF: Should I check the waveforms at
the resonant frequecies. Should I assemble the board in particular
sequence.

Q) Are there any general methods of making sure that the LC BPF
circuits will work.

BR
Madhukar