Cable Box generating radio noise?

[YamahaFreak]

(Not sure if this is in the appropriate board or not.)

I was testing a new radio I found, tuning around on its manual weather band, when I came across a very weird set of tones and warbling somewhere in the vicinity of 162.6xx MHz. I turned stuff on and off to trace the noise to my Scientific Atlanta Explorer 3250HD cable box (Bright House/TWC). The pitch of the sound starts high when the box is plugged in, and changes pitch several times until settling at a lower frequency until the channel is changed. (it's always a steady frequency, not a sweep)

Why would my box be radiating radio noise at this frequency, and what's it using it for, if anything? You'd be completely oblivious to it unless a radio near to the unit was tuned to the frequency it's transmitting on. It doesn't bother me at all - I'm just very highly intrigued and fascinated!

EDIT: Further testing reveals another noise at a slightly higher frequency - a constant 1,000 Hz (?) tone that changes waveform when buttons are pressed and channels are changed. This sound also changes markedly whenever the LED display on the front of the box changes. Intriguing...