Hi everyone, in the “RPi’s Supported” section of the Raspberry Shake documentation (Technical Specifications), it states:
“We do not recommend using the Raspberry Pi Zero (any version). Be aware that this version of the Raspberry Pi computer introduces high amplitude RF noise into the Raspberry Shake, seriously compromising the seismic signal by introducing high amplitude low-frequency spikes.”
According to this, the Pi Zero generates high-amplitude RF noise that compromises the quality of seismic signals. Does anyone know why the Pi Zero behaves this way compared to other models like the Raspberry Pi 3 or 4? Is it due to design, components, or something else? I’d appreciate any technical insights or shared experiences. Thanks!
We suspect (from our tests with the Pi Zero) that either how power is managed on such a small board, or increased interference from the onboard WiFi module, or a combination of both was the reason behind the increased RF interference we detected.
This is also why we, in a more general way, recommend not to use the onboard WiFi on our Raspberry Shakes.
Considering the increased RF interference with the Pi Zero, are there any practical ways to mitigate this issue? For instance, would applying electromagnetic shielding (EMC shielding) to the board or specific components help reduce the noise levels? Alternatively, could adjustments in the setup or external hardware potentially minimize the interference?
I’d appreciate any suggestions or insights on this. Thanks again!
To my knowledge, we have not tried to apply a shield to individual components, but it could be considered if you want to experiment a bit and see what kind of results this solution could provide.
I think our development team has tested different configurations and possible setups (I don’t have details on such tests), but with no luck, as the interference levels were always above the acceptable limits, introducing too much noise in the recorded seismic signal.
I am also interested in this, I am trying to reduce the size, power consumption, and (therefore) portability of my Shake.
Per the information here: Technical Specifications, it seems like only 11 pins are being used by the Shake?
You do not need to answer about the viability of reducing the RF interference reduction, but if you were to individually connect just those 11 pins between the Pi board and the Shake board (for testing purposes, say, with breadboard jumper cables or the like)…would the Shake work just fine?
If so, I might experiment with physically separating a zero board from the shake board/geophones and seeing if that works.
Yes, even if the Shake board connector covers all pins between 01 and 26, it actually uses only 11 of them.
I don’t know if this has been tried, but yes, if you managed to connect all pins between the two boards solidly, I think you could proceed with your test. You could also use a GPIO extender cable to achieve this.
However, if the extender cables are too long, you could start seeing more and more “noise” in what you record, so you should find (if possible) a separation distance that allows good data transmission and the least possible amount of noise.