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ESP32-C3 SuperMini antenna modification

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Re: ESP32-C3 SuperMini antenna modification

#2
Antenna design is a dark art, I like simple hacks like this.

> The two parts of the antenna are intentionally designed to create an omnidirectional radiation pattern without a pronounced directionality.

I worked on a project a while back to try to utilize this to detect the arrival direction of WiFi signals approximately based on received strength. Do this for enough base stations and you have a very crude positioning system.

Re: ESP32-C3 SuperMini antenna modification

#3
post #2

Antenna design is a dark art, I like simple hacks like this. > The two parts of the antenna are intentionally designed to create an omnidirectional radiation pattern without a pronounced directionality. I worked on a project a while back to try to utilize this to detect the arrival direction of WiFi signals approximately based on received strength. Do this for enough base stations and you have a very crude positionin…

It also immediately invalidates FCC modular component compliance, and may be illegal if operating on dual-use bands like 5G wifi.

Remember the rules limits use the ERP, and EEs may have added a crappy antenna on purpose to meet the legal limits.

https://en.wikipedia.org/wiki/Effective_radiated_power

There are also medical radiofrequency exposure guidelines, and they mitigate deep tissue burns or "G5 Mind control beams" concerns. lol =3

https://www.canada.ca/en/health-canada/services/health-risks...

Re: ESP32-C3 SuperMini antenna modification

#4
post #2

Antenna design is a dark art, I like simple hacks like this. > The two parts of the antenna are intentionally designed to create an omnidirectional radiation pattern without a pronounced directionality. I worked on a project a while back to try to utilize this to detect the arrival direction of WiFi signals approximately based on received strength. Do this for enough base stations and you have a very crude positionin…

It also immediately invalidates FCC modular component compliance, and may be illegal if operating on dual-use bands like 5G wifi. Remember the rules limits use the ERP, and EEs may have added a crappy antenna on purpose to meet the legal limits. https://en.wikipedia.org/wiki/Effective_radiated_power There are also medical radiofrequency exposure guidelines, and they mitigate deep tissue burns or "G5 Mind control beam…

Exactly… they would have added crappy antenna as they likely meet emission, spurious or harmonics requirements..

Engineer might be messing with other 2.4GHz devices by doing this

Re: ESP32-C3 SuperMini antenna modification

#5
post #2

Antenna design is a dark art, I like simple hacks like this. > The two parts of the antenna are intentionally designed to create an omnidirectional radiation pattern without a pronounced directionality. I worked on a project a while back to try to utilize this to detect the arrival direction of WiFi signals approximately based on received strength. Do this for enough base stations and you have a very crude positionin…

It also immediately invalidates FCC modular component compliance, and may be illegal if operating on dual-use bands like 5G wifi. Remember the rules limits use the ERP, and EEs may have added a crappy antenna on purpose to meet the legal limits. https://en.wikipedia.org/wiki/Effective_radiated_power There are also medical radiofrequency exposure guidelines, and they mitigate deep tissue burns or "G5 Mind control beam…

You can just ignore the FCC.

They are completely toothless.

Re: ESP32-C3 SuperMini antenna modification

#6

Earlier quoted context omitted.

It also immediately invalidates FCC modular component compliance, and may be illegal if operating on dual-use bands like 5G wifi. Remember the rules limits use the ERP, and EEs may have added a crappy antenna on purpose to meet the legal limits. https://en.wikipedia.org/wiki/Effective_radiated_power There are also medical radiofrequency exposure guidelines, and they mitigate deep tissue burns or "G5 Mind control beam…

You can just ignore the FCC. They are completely toothless.

As an individual this is mostly true unless you're touching broadcasting proper. As a business this is absolutely not true and noncompliance is a ticking time bomb that will bankrupt you.

Re: ESP32-C3 SuperMini antenna modification

#7

Earlier quoted context omitted.

It also immediately invalidates FCC modular component compliance, and may be illegal if operating on dual-use bands like 5G wifi. Remember the rules limits use the ERP, and EEs may have added a crappy antenna on purpose to meet the legal limits. https://en.wikipedia.org/wiki/Effective_radiated_power There are also medical radiofrequency exposure guidelines, and they mitigate deep tissue burns or "G5 Mind control beam…

You can just ignore the FCC. They are completely toothless.

[deleted]

Re: ESP32-C3 SuperMini antenna modification

#8
post #4

Earlier quoted context omitted.

It also immediately invalidates FCC modular component compliance, and may be illegal if operating on dual-use bands like 5G wifi. Remember the rules limits use the ERP, and EEs may have added a crappy antenna on purpose to meet the legal limits. https://en.wikipedia.org/wiki/Effective_radiated_power There are also medical radiofrequency exposure guidelines, and they mitigate deep tissue burns or "G5 Mind control beam…

Exactly… they would have added crappy antenna as they likely meet emission, spurious or harmonics requirements.. Engineer might be messing with other 2.4GHz devices by doing this

2.4GHz is already incredibly crowded and prone to interference (in urban environments). I remember once picking up emissions on a Bluetooth headset from a leaky microwave oven.

Re: ESP32-C3 SuperMini antenna modification

#9
post #2

Antenna design is a dark art, I like simple hacks like this. > The two parts of the antenna are intentionally designed to create an omnidirectional radiation pattern without a pronounced directionality. I worked on a project a while back to try to utilize this to detect the arrival direction of WiFi signals approximately based on received strength. Do this for enough base stations and you have a very crude positionin…

I'm doing something similar, using the directionality of the antenna to turn an ESP32 into a high RPM gyroscope for use in a combat robot. Standard gyro chips top out well under 1000 RPM, and are much more expensive than an ESP32 board, plus the ESP can serve as the radio control link and brain of the bot at the same time.

Re: ESP32-C3 SuperMini antenna modification

#10
post #4

Earlier quoted context omitted.

It also immediately invalidates FCC modular component compliance, and may be illegal if operating on dual-use bands like 5G wifi. Remember the rules limits use the ERP, and EEs may have added a crappy antenna on purpose to meet the legal limits. https://en.wikipedia.org/wiki/Effective_radiated_power There are also medical radiofrequency exposure guidelines, and they mitigate deep tissue burns or "G5 Mind control beam…

Exactly… they would have added crappy antenna as they likely meet emission, spurious or harmonics requirements.. Engineer might be messing with other 2.4GHz devices by doing this

This seems very unlikely compared to the obvious answer that they added a crappy antenna to keep their BoM and assembly costs low.

The radios on these are weak and adding an Omni antenna is exceptionally unlikely to violate EIRP.

Could this design accidentally radiate something it's picking up from the board outside of 2.4ghz? Sure.

But practically it's quite unlikely to in this context.

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