Question

1. Calculate the wavelength of a waveform given a period of 17μs.
2. Find the input thermal noise voltage of a receiver with a bandwidth of 3.33 kHz, with an input resistance of 42 Ω, and a temperature of 29^oC.
3. Given the signal power of 2.3 μW and the noise power of 0.7 μW, calculate the signal-to-noise ratio.
4. Three (3) AM broadcast stations are spaced at 18 kHz, beginning at 73 kHz. Each station is allowed to transmit modulating up to 6 kHz. Compute for the upper and lower sidebands of each station.
5. Given a dc bias of 0.5mA and a bandwidth of 10 kHz, calculate for the noise current.

Answer 1

1.

the wavelength:

$\lambda=vT$

where v is wave speed,

T is period

$\lambda=17v$