# Questions regarding electrical inertia and multi-bandpass filters

Discussion in 'General Electronics Chat' started by JethroTull, Oct 3, 2014.

1. ### JethroTull Thread Starter New Member

Sep 3, 2014
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0
Problem nr1.

By considering the basics of the components of electricity(magnetism and dielectricity) and hence the way condensers and inductors behave, and hence the parallell RLC circuit.
How do i make the oscillation between the inductor(s) and the condenser(s) more inert in the sense that the oscillation between it lasts as long as possible when i remove the power source from the circuit, and the resistor ,in this case for simplicity, is a lamp between the L and C.
Since my knowledge is superficial and theoretical.

The higher the inductance and capacitance the higher the electrical inertia.
But when the energy storage becomes high wont it become a filter and hence try to kill the oscillation when the frequency is low (30-400hz)?

Question nr2.

How do i make a multi-bandpass filter from different filters so that their properties dont mix with each other creating another different filter.

2. ### MikeML AAC Fanatic!

Oct 2, 2009
5,451
1,070
Look up the concept of Q.
Q depends mostly on losses in the inductor. Find an inductor with lowest possible series resistance relative to its inductance, and make the capacitive reactance large as practical...

3. ### Bernard AAC Fanatic!

Aug 7, 2008
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476
Might try looking up " comb filter ".

4. ### Papabravo Expert

Feb 24, 2006
11,072
2,152
A comb filter just adds a delayed version of itself or the output. See the following:
http://en.wikipedia.org/wiki/Comb_filter
The magnitude response is periodic, but I would hardly characterize it as a practical band pass filter because the skirts are not very steep and you have no control over the center frequencies and bandwidths of the multiple passbands.

So:
Analog filters can be placed in parallel with each other and their outputs added together. Buffering can prevent any of the filters from affecting the others.