On the bottom of my portable CD player is this blurb:
By the end of that, I’m imagining a van outside my house marked “Dry Cleaners”, and inside, one cop is pointing a transmitter at my window and saying to the other, “heh heh, this will teach him to listen to Aqua!”
(1) is straightforward enough, but what does (2) mean? Why does it need to “accept any interference received”, and what would constitute not accepting it?
I think it means that it must function properly when being interferred with to the extent that regulations allow other devices to produce electronic noise.
But it says it must even accept interference that causes “undesired operation”, which sounds to me like it’d be functioning improperly.
It seems to me that the langauge of FFC Rules Part 15 could have been more precise, as regards the correct English meanings of words like, may, might, and must, along with their negatives.
The intent of the rule is that these devices MUST NOT emit radio frequency (RF) energy that interferes with other FCC licensed communications and communication devices (e.g. radios and TVs), and that they MAY have to put up with RF interference from other licensed devices. There is no requirement against shielding your device to make it impervious to RFI…you (or most likely the manufacturer of your portable phone, TV, VCR, etc.) are free to shield the device as well as you wish. This is frequently an expensive proposition, which is why so many consumer electronic devices are so prone to RF interference.
KN6SU
I’ve looked at it as a ‘cover my ass’ clause. If your radio picks up static (RF radiation that causes undesired operation) you can’t sue anyone for making a faulty product. Ditto for your TV set. Ditto for your CD player. In theory, anyway. I can’t think of how radio waves could interfere with a CD player. Short of frying it, that is.
Looking down, I see I’ve repeated Neurodoc. Oh, well. Maybe I was more clever. 
Another comment: as a Ham Radio Operator, I have to make sure my station emits “clean” RF signals. Despite the fact that I do everything in my power to operate an FCC compliant station, I have had neighbors complain about radio, phone, and TV interference. Since I have a big 35’ antenna perched on my roof, I’m an easy target for any and all complaints from my neigbors, including a psycho who said I was transmitting signals into his dental work (I kid u not).
Basically, what Part 15 does is to ensure that if MY authorized RF emitting station is compliant with all FCC regulations, then the poor schmuck whose cheaply made TV or other consumer electronic gadget can’t get the FCC to close down my station. The poor schmuck needs to fix the cheap crap that he bought at the Good Guys, Circuit City, Radio Shack, or wherever…