... for beginners who are new to RF like me, and even the cheapest RF power meters cost hundreds of RMB. For electronics enthusiasts who follow the principle of "spend when you should, save when you can", DIYing an RF power meter is a great alternative. The first step WAs to define the functions and design the hardware circuit. To test RF power, a chip called a detector is required. I had not found a suitable option for a long time as it WAs my first time working with an RF detector, until I saw the power detection module on the E25-C test baseboard, which use ...

How is this negative? I just Pointed out there's no Point in upgrading if you already have the original Pico. You hardly require additional memory and power for most of the projects that Pico 1 can't handle

@nathan I personally think if you already own a PICO or PICO W and not utilizing it to its full extent, there's no Point in upgrading. Because the PICO 2 does not have a USB C which is a major turndown. But obviously, if you WAnt to try the RISC-V, it's one of the best options considering the community support.

Measuring a transformer with an oscilloscope, especially in mains-powered circuits, requires caution to avoid damaging your equipment or risking personal safety. One major risk comes from grounding. Most benchtop oscilloscopes connect their probe ground clips directly to earth ground through the power cord. If you attach the ground clip to a Point in the transformer circuit that isn’t referenced to earth ground—such as a floating secondary—you can unintentionally create a short circuit. This short can damage the oscilloscope, harm the transformer, or even cause electric shock. To prevent this, always ensure the oscilloscope and the circuit under test share the same ground reference. If that’s not possible, use an isolation transformer to power the circuit. This isolates it from the mains ground, allowing you to safely connect the oscilloscope. You can also use a differential probe, which measures the voltage between two Points without relying on a common ground. This makes it ideal for measuring floating or ungrounded circuits. You also need to pay attention to voltage ratings. Oscilloscopes and their probes can only handle a limited amount of voltage. If you exceed that limit, you risk damaging both the probe and the oscilloscope. To stay within safe limits, use attenuating probes like 10:1 or 100:1 when working with high voltages, and always verify the maximum input ratings before connecting anything. Improper connections can also cause short circuits and overloads. If you connect probes incorrectly or create a ground loop, large currents might flow through unintended paths. This can burn out transformer windings, destroy probes, or even start fires. To stay safe, always double-check your connections before powering the circuit. Set the oscilloscope’s input impedance correctly to avoid incorrect readings or signal distortion. When working with floating circuits, rely on isolation techniques or differential probes to create a safer test environment. If you follow these steps you can surely measure a transformer with an oscilloscope but make sure safety first.

A good rule of thumb when reading resistor color codes is to start from the end where the color band is closest to the lead. That first band usually marks the most significant digit, so if one side has a band that's clearly closer to the edge than the other, that’s your starting Point. For instance, in many 4-band resistors, you’ll see something like red on one end and gold on the other. The gold band is usually spaced a bit farther from the edge, and since gold and silver are never used as the first digit, that’s a solid hint they mark the tolerance and should be read last. Resistors can have up to 6 color bands, with the extra ones representing things like tolerance and temperature coefficient. These can be a bit trickier to read, but once you're familiar with the basic rules, it gets easier. Here’s a quick breakdown: 4-Band Resistor 1st Band = 1st digit 2nd Band = 2nd digit 3rd Band = Multiplier (i.e., how many zeros to add) 4th Band = Tolerance (accuracy) Example: Red (2), Violet (7), Orange (×1,000), Gold (±5%) → 27,000 ohms or 27kΩ ±5% If you still find it tricky, you can use an online calculator to make things easier: 👉Resistor Color Code Calculator

Yep, you're on the right track—mechanical switch bounce is the most likely culprit here. Mechanical contacts don’t just close once—they physically bounce for a few milliseconds, causing multiple rapid transitions that your SR latch interprets as separate inputs. That’s why you're seeing multiple or unstable output changes. To fix this issue, I recommend using a resistor and capacitor on the input line. A typical starting Point is a 10kΩ resistor and a 0.1µF capacitor. This will help smooth out the bounce. Also, make sure the inputs aren’t floating and are properly pulled up or down. That should clean up the behavior of your SR latch.

Yeah, losing the neutral in a 3-phase 4-wire system can cause major issues, especially if the loads aren’t balanced (which they usually aren't in real-world setups like homes or small businesses). What actually happens is this: the neutral Point “floats” because there's no solid reference anymore. So instead of each phase staying around 230V, the voltages start to shift depending on the loads on each phase. Light load = lower voltage, heavy load = higher voltage. In the worst cases, one phase might go up to nearly 400V—way more than your appliances are built for. As a result, you'll see major voltage fluctuations in your supply. There are protection relays and devices that can catch this (like a phase failure relay or neutral monitoring), but not every system has them—especially older setups. In short: broken neutral = unpredictable and often destructive voltage swings. A real pain to troubleshoot if you don’t catch it quickly.

I’ve read that a broken neutral in a 3-phase 4-wire system can cause serious problems, especially in systems with unbalanced loads, but I’m not entirely clear on what exactly happens when the neutral is lost. Let’s say the system is supplying a mix of single-phase loads (like in a commercial or residential setup). If the neutral breaks at some Point—what are the actual consequences for the connected loads? Do voltages across phases shift dangerously? Can it damage appliances or equipment? How does the system behave differently under balanced vs. unbalanced load conditions? I’m looking for a practical explanation of what happens electrically and what kind of damage or safety risks it introduces. Real-world examples or typical protection mechanisms would be great too. Thanks!

Decoupling capacitors are essential for stabilizing the power supply and suppressing noise in microcontroller and digital circuits. A common starting Point is placing a 100 nF ceramic capacitor (X7R type recommended) close to the Vcc and GND pins of each IC to handle high-frequency transients. To support sudden current demands and filter lower-frequency noise, it's also good practice to add a bulk capacitor—typically 1 µF to 10 µF—near the microcontroller or groups of ICs. The exact values depend on several factors, including the switching speed of the ICs, current consumption, and the quality of the PCB layout. Faster ICs may require additional smaller capacitors like 10 nF or 1 nF in parallel with the 100 nF to cover a broader frequency range. High-current circuits may benefit from larger bulk capacitors up to 47 µF. Proper placement is critical—capacitors should be located as close as possible to the power pins, with short, direct traces. Using a mix of capacitor values in parallel helps improve overall decoupling performance. While 100 nF is a solid default, evaluating layout and load conditions can help you fine-tune your choices for a more robust and reliable design.

When you simply connect an oscilloscope to a signal, the screen may show a WAveform that appears unstable, jittery, or rolling. This happens because the scope doesn’t know when to start drawing each WAveform—it just keeps refreshing as data comes in. That’s where the trigger comes in. The trigger tells the oscilloscope when to begin drawing the WAveform on the screen. It locks the display to a specific event—like when the signal crosses a certain voltage level going up (rising edge) or down (falling edge). By doing this, it ensures that each sweep starts a ...

You're absolutely right—when moving into high-frequency PCB design (in the MHz to GHz range), layout becomes critical for ensuring signal integrity and performance. At these frequencies, traces behave like transmission lines, so maintaining controlled impedance is essential. For most RF applications, a 50-ohm microstrip or stripline trace is standard, and you’ll need to calculate trace width based on your PCB stack-up, dielectric material, and copper thickness. Trace layout should avoid right-angle bends, use 45° angles or curves, and keep high-speed traces as short and direct as possible. Differential signals (like USB or LVDS) require matched trace lengths and consistent spacing to maintain impedance and minimize skew. The PCB stack-up plays a huge role in high-frequency performance. It's best to place signal layers adjacent to solid ground planes to provide a continuous return path and minimize loop area, which helps reduce EMI. A 4-layer or higher board with dedicated power and ground planes is generally recommended. When choosing a stack-up, consult your PCB fabricator to ensure the dielectric thicknesses and materials support your impedance requirements. Common mistakes in high-speed PCB design include failing to provide a solid ground reference under signal traces, using excessive or poorly placed vias that introduce unwanted inductance, and improperly terminating high-speed lines, which can result in reflections and ringing. Power integrity is also crucial—decoupling capacitors should be placed close to power pins, and using a mix of values helps cover a wider frequency range. Lastly, improper grounding between analog and digital sections can lead to noise coupling, so careful partitioning or single-point grounding is advised. With proper attention to these details and the use of simulation tools, designing high-frequency PCBs becomes much more manageable and repeatable.

... to bake a cake. Your loop() function is carefully measuring flour, mixing ingredients, and so on. Now, what if the doorbell rings? Without interrupts (the loop() WAy): You'd have to finish a major step in your recipe (like mixing the batter) and then quickly run to the door to check if anyone is there. If your recipe step takes a long time, your visitor might get impatient and leave. This is called polling – repeatedly checking the state of something. With interrupts: The moment the doorbell rings, you'd immediately pause what you're doing (even if you're ...

I feel like you are referring to Earthing(in Electrical systems) but got confused between Earthing and Grounding. Let me explain: Grounding in electronics provides a common return path for the current. Without a proper ground reference, your circuit just won’t function reliably. Even a simple LED needs a return path to complete the loop. And it’s not just a good design habit, it’s a foundational principle for how circuits work. In digital and analog systems, ground acts as a voltage reference Point. For instance, when you say a signal is 5V, it means 5V above ground. Earthing (also called grounding in some countries) in an electrical system means physically connecting certain parts of the electrical installation—like the metal frames of appliances to the Earth using a low-resistance wire. If a fault occurs and a live wire touches a metal body (like your fridge), earthing provides a direct path to the ground. This causes a large current to flow, which trips the breaker or blows a fuse—disconnecting the supply quickly and protecting people from electric shock. But here's a thing: Your Electrical system/appliances will still work without earthing, but it is very risky. So in conclusion, grounding in electronics is very different from Earthing in an Electrical system.