Optional Noise

[nealey]

Users have requested the ability to make it noisier.

The type of noise they want is very specific, though. They want to, as faithfully as possible, mimic the noise you would get when using a narrow band-pass filter on an actual radio transmission.

There are examples of different types of noise on YouTube with the search term "QSO". Specifically, what I think would be helpful is to have sliders where you can go from none to full on the following types of noise:

• Static: just white nose with a bandpass filter centered on the rx tone frequency (I think this is how it works, not positive).
• dB fade: feed an oscillator into the gain for the tone generator, and modulate the frequency of that oscillator with some sort of random number generator (maybe even the source buffer for the white noise generator).
• Industry: More white noise, but its gain is controlled by an oscillator. Maybe this could be combined with Static somehow? Maybe a base value and a sine wave amplitude?
• High pass filter with cutoff frequency driven by an oscillator.
• Lightning: periodic bursts of pink noise. More lightning = more frequent bursts.
• Nuclear war: Lightning but with a really long decay and higher gain.
• Alien invasion: take the output of a therimin type "ray gun" sound effect and use that to modulate... something. A high-pass filter? Maybe add a tone?

[nealey]

What you get, for the time being, is two white noise generators, each with a bandpass filter driven by an oscillator. One is centered around 400Hz with a duty cycle of 0.07Hz, the other is centered around 1600Hz with a duty cycle of 0.03Hz. There's a volume slide for the whole works.

[nealey]

Jason suggested it would be better if the noise gain went up and down. Should be a matter of just hooking an oscillator up to it, right? But I can't get that working right.

Writing this down because I may not have time to look at this again for a while.