Transmission is blocked

Trying to emulate my Hunter ceiling fan remote. Steps:

  1. frequency analyzer on the remote detected 303.875 (multiple times)

  2. set the readRaw config to 303.87

  3. pressed the remote button and recorded readRaw successfully

  4. played what was recorded and got ‘transmission is blocked’

According to Frequencies - Flipper Zero — Documentation flipper only broadcasts in this range in the U.S.: 304.10 - 321.95 MHz, which explains the transmission is blocked message.

My question is why is Flipper being forced to block 303.87 if it’s a legal frequency being used by fan companies?

I’ve seen other posts with similar problems, but this particular question is not answered.

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Something is probably out of spec. I’d try to manually edit the raw file to
Frequency: 304100000

Otherwise you may want to update you Flipper firmware to TX out of spec.

Ofcourse that updating the firmware to TX out of spec will not be tolerated/allowed here …

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True, it wouldn’t be legal to transmit to a malfunctioning or non compliant fan.

A little off topic but with my FCC granted Amateur license I may modify a radio to transmit in other frequencies allocated to Amateur radio with certain caveats. I won’t go into detail but broadcasting my FCC call sign is one of those requirements. Anyone interested in that should learn about Amateur radio and possibly get a license. Much of that information is useful even if you don’t want to get the license.

It’s also possible to apply for a temporary FCC license. For instance wireless boot camps/hacker camps apply to run wireless networks. Some run entire phone networks.

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Same problem here. I was hoping to use this thing as a single remote for many locations. My home, my mothers home, another friends home…we all have 300Mhz garage doors and gates. I can save the codes but get a transmission is blocked error when trying to use them. Why is Flipper Zero blocking perfectly normal retail equipment? These all use Multi-Code Linear remotes. You can buy them anywhere. As you can imagine though, I’m tired of many remotes.

This cant be a security issue. I just tested my works DoorKing cards and was able to emulate those (I’m the IT person there). So I can break into huge corporations but I can’t get into my own garage?

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The Flipper Zero was not certified to operate at 300MHz in the US. Doing so would be illegal for us. The garage openers, on the other hand, got certified for 300MHz, so for them it’s not illegal to operate on this frequency. We can’t do anything about this, sorry.

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Just got my Flipper Zero and my first test is just the same: a 300 MHz gate opener - and it can’t do it? Disappointing.