# Tag Info

Accepted

### Why is TV static noise always black and white?

The color burst is also an indicator that there is a color signal. This is for compatibility with black and white signals. No color burst means B&W signal, so only decode the luminance signal (no ...
• 5,006
Accepted

### What sampling frequency should I use if Nyquist is not available?

HINT When you sample at below the Nyquist rate, aliasing happens. That means frequencies higher than half the sampling rate get folded back down to below half the sampling rate. Have a read about ...
• 25.7k

### Why is TV static noise always black and white?

In the absence of a valid color burst signal, the "color killer" circuit disables the color difference signals, otherwise you would indeed see colored noise. This is mainly intended for displaying ...
• 371

### What sampling frequency should I use if Nyquist is not available?

As correctly stated in Peter K.'s answer, this question is about aliasing. Since you can't sample at a rate that is sufficiently high to avoid aliasing - i.e., $f_s>50\textrm{ kHz}$ - you have to ...
• 89.5k
Accepted

• 211

### Why is a bandpass filtered analog PM signal still PM and not AM

Conventional AM and narrowband PM signals look quite similar: $$x_{AM}(t) = A \cos(\omega_c t) + m(t) \cos(\omega_c t)$$ $$x_{NBPM}(t) = A \cos(\omega_c t) - A k_p m(t) \sin(\omega_c t)$$ And based ...
• 28.1k
Accepted

### How basses are reconstructed on small speakers

The acoustic efficiency of a small speaker drops drastically with frequency. The standard way of dealing with this is to simply boost the bass through a linear EQ. However that's limited by the ...
• 44k

### Emulating an analog Oscillator in DSP

That's a fairly broad question. I'm eager to understand how one might emulate an analog oscillator digitally. If you really want to model an analog circuit this is typically done by using ...
• 44k