1. What is a Twin Notch Filter Calculator?

Definition: This calculator determines the notch frequency of a twin-T notch filter based on its inductance and capacitance values.

Purpose: It helps electronics engineers and hobbyists design filters that attenuate specific frequencies while passing others.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( f_n \) — Notch frequency (Hertz, Hz)
• \( L \) — Inductance (Henries, H)
• \( C \) — Capacitance (Farads, F)

Explanation: The notch frequency is inversely proportional to the square root of the product of inductance and capacitance.

3. Importance of Notch Filter Calculation

Details: Accurate notch frequency calculation is essential for eliminating specific interference frequencies while maintaining signal integrity.

4. Using the Calculator

Tips: Enter the inductance in Henries and capacitance in Farads. Both values must be > 0. Common values are in millihenries (mH) and microfarads (μF).

5. Frequently Asked Questions (FAQ)

Q1: What is a notch filter used for?
A: Notch filters are used to eliminate specific frequencies (like 60Hz hum) while passing all other frequencies.

Q2: Why is it called a twin-T filter?
A: The name comes from the circuit configuration which resembles two "T" networks connected together.

Q3: What's the relationship between L, C and the notch frequency?
A: Higher L or C values result in lower notch frequencies, and vice versa.

Q4: How can I adjust the notch depth?
A: Notch depth is controlled by component matching and quality, not by the L and C values alone.

Q5: Can I use this for active notch filters?
A: The formula works for passive twin-T networks, active filters may use different calculations.