An inductive conductivity meter I promised to release it.
There might be plenty of errors.
u/Time-Routine2006 — 6 days ago
▲ 0 r/embedded
In my spare time, I work a bit on issues related to polarization.
Just to clarify: this is a quick 5-second express method for rapid on-site inspection, not a replacement for a laboratory microscope. It allows you to instantly spot hidden bridges and whiskers without even taking the board out of the chassis or adjusting optical gear. Fast, cheap, and mobile.
u/Time-Routine2006 — 1 month ago
Thinking about the physical vacuum led me down a rabbit hole... (and maybe an experiment?)
I was just sitting around thinking—nothing too serious—and I started wondering why we see light from a source and not as a continuous glow everywhere.
The usual answer: photons travel in straight lines. Fine.
But then I thought: why does a photon have no mass, while something like gold does?
Don't all particles interact with the Higgs field?
And this led me down a very long train of thought:
What if mass isn't a fixed property of a particle, but rather the result of how strongly it "resonates" in sync with other particles?
Think of it like a choir.
A single electron = one quiet voice.
Three quarks inside a proton, moving in sync = a strong chord (mass of the proton is 938 MeV, while the quarks themselves are only ~10 MeV).
A gold atom with 79 electrons and its quarks = a massive choir. More resonance = more mass.
Yeah, sounds a bit crazy, I know.
Then I went further:
What if our "deep vacuum" isn't the bottom of everything, but simply a boundary with other layers of reality? Layers that have their own physics, their own fields, maybe even a different speed of light.
The virtual particles we see in the Casimir effect? Maybe they’re not random noise, but projections from those neighboring layers trying to push into ours—and failing, which is why they annihilate so fast.
And what if coordinates in our layer don't match coordinates in theirs? One point here might be a whole "cloud" over there. That could explain entanglement, nonlocality, wave-particle duality... just a thought.
So, being an engineer, I started thinking: can we test this?
Here's the idea:
Take two materials with different densities.
Build them on top of each other at the atomic level (like a microchip).
Hit them with microwave radiation (100 GHz+), creating a resonance at the boundary.
Suddenly cut the power and see what happens.
Possible outcomes:
The plate heats up → energy released from the vacuum.
The plate cools down → energy absorbed by the system.
Now, this isn't a perpetual motion machine. Energy would come from the neighboring layer, not from nothing. We're just opening a valve, so to speak.
If this worked, we'd be looking at compact energy sources and passive cooling.
If not... well, I just had a fun thought, and I wanted to write it down somewhere. 😄
I'm not a physicist—just an engineer who likes to wonder.
Curious what you think. And if any of this sounds plausible, or if I've completely lost it.
u/Time-Routine2006 — 2 months ago
▲ 20 r/embedded
I've built my first prototype. The inductive EC method seems to work in this configuration (ESP-WROOM-32D + STM32F407VET6 + ADC (DC/DC) + RS485 (STM32) + 18B20 + DHT22 + SSD1306). What else do I need to connect? I'll be making a second version of the board.
A working prototype for inductive liquid conductivity (LC) measurement, currently measuring conductivity in parrots. xD
u/Time-Routine2006 — 2 months ago
▲ 1 r/Hydroponics
Inductive TDS/EC Meter for Monitoring Changes in Dissolved Solids Concentration. Primary Testing. Part 3
Continuing the series on my non‑contact inductive EC/TDS meter. Part 1 covered the concept, Part 2 showed initial frequency sweeps and differences between distilled and tap water.
Part 3 is about calibration, temperature compensation, and a closer look at ion behavior.
I built a thermostatic cell using a Peltier element. The lowest stable temperature I can reliably get is around 8.3°C, so I’m working with a practical calibration range from 10°C to 30°C. I’m currently recording calibration curves for distilled water and a NaCl reference solution (6000 µS/cm) across this range. The sensor response is linear within 10–30°C, which simplifies things.
One interesting observation: inductive sensors respond not only to total conductivity, but also to ion mobility. Two solutions with the same EC but different ions (e.g., NaCl vs MgSO₄) give different readings.
To handle this, I’m introducing a correction factor:
K = inductive reading / EC (contact meter)
K ≈ 1.0→ ions behave like NaClK > 1.0→ more mobile ions (“light”)K < 1.0→ less mobile ions (“heavy”)
This gives not just EC, but also a rough indication of ion type — useful for hydroponics, aquariums, and general water monitoring.
Next steps: complete the calibration curves, test the correction factor with real nutrients, add MQTT logging, and prepare a small batch of boards for early testers.
The project is moving forward. More updates soon.
u/Time-Routine2006 — 2 months ago
▲ 2 r/Hydroponics
Inductive TDS/EC Meter for Monitoring Changes in Dissolved Solids Concentration. Primary Testing. Part 2
Measurements were taken using distilled water (37 µS/cm at 25.1°C) and tap water (414 µS/cm at 25.1°C). The water was in its original state, without any pre-treatment. Measurements were run from 3 kHz to 400 kHz.
Link to chart in excel format: https://docs.google.com/spreadsheets/d/1IAYgtrlVxO6IRboaOY9aEJKo9f_IM9OJ/edit?usp=sharing&ouid=113272371396080140970&rtpof=true&sd=true
I'm currently waiting for a thermostat with a built-in magnetic stirrer. I want to calibrate the device.
u/Time-Routine2006 — 3 months ago
▲ 1 r/Hydroponics
Inductive TDS/EC meter for monitoring changes in dissolved solids concentrations. Initial testing.
The liquid frequency scanning test rig performed measurements in the range from 10 kHz to 240 kHz in 10 kHz increments.
I am sharing the first results of distillate measurements:
According to the first result, the ADC values at 10 kHz are 44653, 20 kHz 33495, 30 kHz 41507, and 40 kHz 41507. There are some camel humps, but from 50 kHz to 170 kHz, the signal is very good. There's a drop from 230 kHz to 240 kHz. It would be worth expanding the range to 500 kHz later... and that's distilled water.
The results for simple running water also show an interesting picture: a significant signal drop is clearly visible, but at frequencies from 230 kHz to 240 kHz there is no sharp drop. The range definitely needs to be expanded; operating frequencies from 50 to 120 kHz are excellent readings for the first time.
u/Time-Routine2006 — 3 months ago
▲ 2 r/Hydroponics
How to eliminate contact oxidation when measuring EC/TDS. Inductive method (proof of concept)
Anyone who tinkers with hydroponics or aeroponics knows: Chinese TDS meters with two protruding contacts are convenient, but they don't measure accurately over time. The contacts oxidize, the salt composition changes, and you have to calibrate them every other time. I decided to try a fundamentally different method—one without direct contact with the liquid.
The core consists of two ferrite rings (tori). One transmits the signal into the liquid (Tx), the other receives it (Rx). The liquid functions as part of the communication circuit. I install a peak detector on the Rx—then the alternating voltage is rectified, and the circuit can be assessed. Any exposed metals in the solution—there's nothing to oxidize.
I won't go into detail about the technical implementation yet; I'm still working on it. But it's already clear that the method works in principle.
This is a preliminary prototype. It doesn't have any contact with the electrodes. You can already see the change in size when adding salt to the water. The fact that it works is encouraging.
u/Time-Routine2006 — 3 months ago