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28 lines
2.3 KiB
Markdown
28 lines
2.3 KiB
Markdown
# Fun with Restaurant Pagers
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Officially supported frequencies: 300-348 MHz, 387-464 MHz, and 779-928 MHz (from [CC1101 chip docs](https://www.ti.com/product/CC1101))<br>
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Unofficially supported frequencies: 281-361 MHz, 378-481 MHz, and 749-962 MHz (from [YARD Stick One](https://greatscottgadgets.com/yardstickone/) CC1111 docs)
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Official currently does not allow anything outside of the officially supported CC1101 specs.<br>
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RogueMaster & CodeGrabber (Unleashed) allows unofficially supported frequencies with the `extend_range` and `dangerous_settings` files.
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**NOTE: Going outside the officially supported frequencies may DAMAGE YOUR FLIPPER AMP.<br>
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Please understand what you're doing if trying to break out of official frequencies.**
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Here's what the [manufacturer of the chip (CC1101) says](https://e2e.ti.com/support/wireless-connectivity/sub-1-ghz-group/sub-1-ghz/f/sub-1-ghz-forum/1120743/cc1101-operation-outside-datasheet-frequencies/4154832) about going outside the limits:
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```
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The frequency range of the chip is always tested in the verification tests and there is always some design margin included before
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the VCO and/or PLL has problems operating for a specified frequency range. Working outside the frequency range can cause issues
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with the VCO and/or PLL and/or divider not operating correctly. If the VCO is operating outside it's standard frequency range,
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there are risks of unwanted emissions and no oscillation. The PLL can also fail to lock if operating outside it's standard
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frequency range and will still apply power to the antenna.
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Risks with antenna mismatch are increased harmonics, reduced output power and increased current consumption. Generally, the antenna
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mismatch can be large and the output stage will not be damaged when presented with a large mismatch for short periods of time.
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However, if the antenna mismatch is very poor for long periods of time, then this can effect the longevity of the chip especially
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if further stressed with maximum voltage and maximum temperature. Recommend keeping VSWR better than 5:1 for worst case scenarios.
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```
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You'll need to edit some code and recompile if you want to break outside of the officially supported frequencies. [Proceed with caution.](https://github.com/UberGuidoZ/Flipper/blob/main/Sub-GHz/Restaurant_Pagers/SubGHz_changes.md)
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