Electrical And Electrionics PE

CRITICAL: Modulation index must be ≤ 1 to avoid overmodulation and distortion. Values between 0.8-1.0 provide maximum efficiency without distortion. Remember that m = 1 corresponds to 100% modulation.

Antenna gain compares directional radiation to isotropic (uniform) radiation. Remember that 3 dB = 2:1 power ratio, 10 dB = 10:1 ratio, 20 dB = 100:1 ratio. Gain can never be negative for passive antennas - this would violate conservation of energy.

Remember that 0 dB corresponds to unity gain (|H(jω)| = 1). Positive dB values indicate amplification, negative values indicate attenuation. The -3 dB point is where |H(jω)| = 0.707, commonly used to define cutoff frequencies.

De Morgan's laws are fundamental for digital logic simplification. Remember both forms: NOT(A+B) = NOT(A)·NOT(B) and NOT(A·B) = NOT(A)+NOT(B). These laws allow conversion between AND/OR operations by inverting inputs/outputs, essential for gate-level circuit optimization.

Remember voltage polarity convention: rises are positive, drops are negative when traversing the loop. Always define a consistent direction around the loop. KVL applies to ANY closed path, not just single loops.