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The article says the FCC must test all radio devices, but that's not true at all. The manufacturer is responsible for testing the device to ensure it meets FCC

by mark-r 9y ago

The article says the FCC must test all radio devices, but that's not true at all. The manufacturer is responsible for testing the device to ensure it meets FCC regulations.

rwmj 9y ago
I'd also be a bit surprised if the FCC were involved with FM radio receivers. Can you not make a simple transistor radio in the US without getting it approved by the FCC?
- culturestate 9y ago
  To your specific question: no, I don't think a transistor radio would require certification unless it was somehow RF emissive. On a broader level, making things without the FCC is fine unless you start disrupting communications networks; selling them is a different issue. In reality, all of this testing and certification is done by independent laboratories and the FCC mostly just makes sure the compliance paperwork is in order.
  - metaphor 9y ago
    > To your specific question: no, I don't think a transistor radio would require certification unless it was somehow RF emissive. How would you know your device wasn't RF emissive if it was never tested? By design, sure, but that doesn't account for radiated spurious emissions.
  - makomk 9y ago
    Depending on the exact architecture used, it's surprisingly easy to accidentally leak your first IF oscillator out the antenna port and broadcast it to everyone in the area. The FCC seems to be relatively lenient about FM radio receivers in general though and let manufacturers self-certify their compliance with the rules without any independent testing.
- metaphor 9y ago
  Sure, but the set of rules applicable to one-off hobbyists are different from commercially manufactured/mass distributed electronics.
- deleted 9y ago
  [deleted]
- jdietrich 9y ago
  Home-built devices made in quantities of five or less do not generally need FCC authorization. Most commercially-made electronic devices are subject to FCC authorization regardless of whether they're intended to act as a radio transmitter, because of the possibility of unintended electromagnetic emissions. The local oscillator in a superhet radio receiver, the clock in a digital circuit or the switching frequency of a switched-mode power supply could create harmful interference. The latter is notorious for causing interference today, but TV and radio receivers used to be a significant cause of interference. FM broadcast receivers are subject to verification, which is the lowest tier of authorization and is essentially a self-certification process; the manufacturer must ensure that the product complies with FCC standards, but the testing does not need to be performed by an accredited laboratory. https://www.ecfr.gov/cgi-bin/text-idx?SID=c4285cfe54bf6085bc13a9437ab0957f&mc=true&node=pt47.1.15&rgn=div5 https://www.ecfr.gov/cgi-bin/text-idx?SID=c4285cfe54bf6085bc...

by mark-r 9y ago

The article says the FCC must test all radio devices, but that's not true at all. The manufacturer is responsible for testing the device to ensure it meets FCC regulations.

rwmj 9y ago

I'd also be a bit surprised if the FCC were involved with FM radio receivers. Can you not make a simple transistor radio in the US without getting it approved by the FCC?

culturestate 9y ago
To your specific question: no, I don't think a transistor radio would require certification unless it was somehow RF emissive. On a broader level, making things without the FCC is fine unless you start disrupting communications networks; selling them is a different issue. In reality, all of this testing and certification is done by independent laboratories and the FCC mostly just makes sure the compliance paperwork is in order.
- metaphor 9y ago
  > To your specific question: no, I don't think a transistor radio would require certification unless it was somehow RF emissive. How would you know your device wasn't RF emissive if it was never tested? By design, sure, but that doesn't account for radiated spurious emissions.
- makomk 9y ago
  Depending on the exact architecture used, it's surprisingly easy to accidentally leak your first IF oscillator out the antenna port and broadcast it to everyone in the area. The FCC seems to be relatively lenient about FM radio receivers in general though and let manufacturers self-certify their compliance with the rules without any independent testing.
metaphor 9y ago
Sure, but the set of rules applicable to one-off hobbyists are different from commercially manufactured/mass distributed electronics.
deleted 9y ago
[deleted]
jdietrich 9y ago
Home-built devices made in quantities of five or less do not generally need FCC authorization. Most commercially-made electronic devices are subject to FCC authorization regardless of whether they're intended to act as a radio transmitter, because of the possibility of unintended electromagnetic emissions. The local oscillator in a superhet radio receiver, the clock in a digital circuit or the switching frequency of a switched-mode power supply could create harmful interference. The latter is notorious for causing interference today, but TV and radio receivers used to be a significant cause of interference. FM broadcast receivers are subject to verification, which is the lowest tier of authorization and is essentially a self-certification process; the manufacturer must ensure that the product complies with FCC standards, but the testing does not need to be performed by an accredited laboratory. https://www.ecfr.gov/cgi-bin/text-idx?SID=c4285cfe54bf6085bc13a9437ab0957f&mc=true&node=pt47.1.15&rgn=div5 https://www.ecfr.gov/cgi-bin/text-idx?SID=c4285cfe54bf6085bc...