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That's not accurate. You absolutely can spin up a transmitter as a DIY project, as long as you stay within the power and duty cycle limits. Devices not intended

That's not accurate. You absolutely can spin up a transmitter as a DIY project, as long as you stay within the power and duty cycle limits. Devices not intended for eventual sale don't even have to be tested or certified, as long as the builder/user makes a good-faith effort to comply with the regulations. A ham license moves you into a different set of limits and gives you more bands to play in, that's all. Take a read of https://www.ti.com/lit/an/swra048/swra048.pdf https://www.ti.com/lit/an/swra048/swra048.pdf for a reasonably cogent summary of the regulations. The FCC's own rules are considerably denser legalese, and the relevant parts are scattered over hundred of pages. That app note brings it all together. More: https://transition.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet63/oet63rev.pdf https://transition.fcc.gov/Bureaus/Engineering_Technology/Do... (See the "Home-built transmitters that are not for sale" section.)

spectramax 8y ago
You're probably correct as I do not have any background in Radio. My point was simply that this article should have mentioned something related to radio frequencies and how it is regulated. It does disservice by telling readers nothing about regulations. This is terrible journalism.
tzs 8y ago
That TI document is a nice look at the regulations that concern the device designer. There are also some regulations that the device user needs to comply with that you don't automatically get for free by using a compliant device. I didn't see those in the TI document, but may have missed them. Probably the most important are for interacting with other services that share that band. A band might have several services authorized to use it, and these services have different priorities in case of conflict. Generally, the rule is if a higher priority service interferes with you, it is up to you to filter it out or tolerate it. If you interfere with a higher priority service, it is up to you to stop. For example, the lower part of the 2.4 GHz WiFi band overlaps the higher part of the 13 cm ham band. Hams have higher priority. So if I were to use that band for some long range telemetry (I have an Extra class ham license) and that messes with you using the lower WiFi channels, you are the one who has to find a workaround. If your WiFi messes up my telemetry, you are again the one who has to find a workaround. On the other hand, part of 13 cm is an Industrial, Scientific, and Medical (ISM) band. That ISM band has higher priority than the ham band. If your microwave oven messes up my telemetry, I'm the one who has to cope, because microwave ovens are classified as and operated as ISM devices. And if my telemetry messes up cooking your burrito, I'm the one who has to deal with it.
- jessaustin 8y ago
  We'd all be impressed and terrified if your telemetry "messed up" a burrito, whether it was in the microwave oven or out.

spectramax 8y ago

You're probably correct as I do not have any background in Radio. My point was simply that this article should have mentioned something related to radio frequencies and how it is regulated. It does disservice by telling readers nothing about regulations. This is terrible journalism.

tzs 8y ago

That TI document is a nice look at the regulations that concern the device designer. There are also some regulations that the device user needs to comply with that you don't automatically get for free by using a compliant device. I didn't see those in the TI document, but may have missed them. Probably the most important are for interacting with other services that share that band. A band might have several services authorized to use it, and these services have different priorities in case of conflict. Generally, the rule is if a higher priority service interferes with you, it is up to you to filter it out or tolerate it. If you interfere with a higher priority service, it is up to you to stop. For example, the lower part of the 2.4 GHz WiFi band overlaps the higher part of the 13 cm ham band. Hams have higher priority. So if I were to use that band for some long range telemetry (I have an Extra class ham license) and that messes with you using the lower WiFi channels, you are the one who has to find a workaround. If your WiFi messes up my telemetry, you are again the one who has to find a workaround. On the other hand, part of 13 cm is an Industrial, Scientific, and Medical (ISM) band. That ISM band has higher priority than the ham band. If your microwave oven messes up my telemetry, I'm the one who has to cope, because microwave ovens are classified as and operated as ISM devices. And if my telemetry messes up cooking your burrito, I'm the one who has to deal with it.

jessaustin 8y ago
We'd all be impressed and terrified if your telemetry "messed up" a burrito, whether it was in the microwave oven or out.