... 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 ...

Definetly not, Dont switch to amps or move the red lead to the A/10A jack while your probes are on a live circuit. In A mode the Meter is basically a short; flipping to it or probing voltage with the lead in A can blow the fuse, make an arc, or worse. Set the Meter and leads with power off, break the circuit, insert the Meter in series, then power up. For mains, use a clamp Meter; for 12 V high-current systems be extra cautious or use a clamp/shunt. And always move the red lead back to V when you’re done to avoid the classic “next-time short.”

Not quite—a 6000-count Meter doesn’t extend the 2V range to 5.999V. The range is fixed by the multimeter, not the count. In the 2V range, both 2000- and 6000-count Meters typically max out at 1.999V. A 6000-count Meter would show up to 5.999V only if it's on a 6V range, not 2V. So, a higher count means better resolution, but the voltage range itself stays the same unless the Meter has a higher range setting.

This usually happens due to the high sensitivity of the multimeter’s continuity mode. Some Meters are designed to beep even with very low resistance, which means slight contact, moisture, or even nearby conductive surfaces can trigger a false beep. However, that's not the only cause. Sometimes, while testing components like Semiconductors or capacitors, residual charge or leakage paths within the component can also cause the Meter to falsely detect continuity. In such cases, the beep doesn't necessarily indicate a true short—it could just be the Meter reacting to a small voltage or current still present in the circuit.

EEPROM and Flash are both non-volatile memories built from floating‑gate transistors, but they differ mainly in write/erase granularity. EEPROM lets you update individual bytes (it internally erases just that byte), giving higher endurance and making it ideal for small, frequently changed settings. Flash must erase larger blocks/sectors and program in pages (you typically erase a whole sector before changing any byte), which makes it cheaper Per bit and faster for bulk storage like firmware and large data.

Yes, the 0.6 V drop you’re seeing is the Meter’s burden voltage, which is the voltage lost across the DMM when it measures current. In mA mode, the Meter places a small internal shunt resistor (and often a fuse or protection components) in series with your circuit to sense current, and this resistance causes a voltage drop equal to V=I×Rmeter​. For example, a 0.6 V drop at 60 mA means the Meter adds about 10 Ω in series, which can significantly affect low-voltage circuits by reducing the actual voltage reaching your load. To minimize this, you can use an external low-value shunt resistor and measure the voltage across it with the DMM in voltage mode, then calculate current using I=V/RI = V/RI=V/R. Alternatively, use a dedicated low-burden current sense amplifier or sensor such as the INA219, a DC clamp probe that measures current without inserting resistance, or the Meter’s 10 A input (which usually has much lower internal resistance) if the current is within safe limits. These methods help keep the measurement accurate without disturbing the circuit’s operating voltage.

... of wire—it has very low resistance. If you try to connect it across a live circuit (like you would for voltage), you're basically shorting the power source, and that can result in Blown fuse in the Meter (if you're lucky), Arcs or sparks. So, If you dont WAnt that Always power off the circuit before measuring current. Break the circuit and insert the Meter in series, making sure the probes are in the correct ports—especially the high current port if you're measuring above ~200mA. Once everything's connected, power on the circuit, take your reading, and t ...

Hi everyone, While checking continuity with my multimeter, I sometimes get beeping sounds even when the probes aren’t actually touching the wires.It seems like a false reading.Could this be due to stray capacitance, interference, or a faulty Meter?

I’ve seen WArnings about using the current (amp) setting on a multimeter, and I WAnt to be cautious. I understand that to measure current, the Meter has to be placed in series with the load. But I’m unsure about the risks involved when doing this on a live circuit, especially with higher voltages like AC mains or even 12V DC systems with decent current. Is it safe to switch to the amp mode while the circuit is powered?

Yes, if you measure current like voltage (in parallel), you can short the circuit and blow the multimeter fuse, or worse, damage it. Also, if the probe is left in the current port and you try to measure voltage, it creates a short path and can seriously damage the Meter or the circuit. Always switch the probe back to the voltage port and check your dial setting before measuring.

For a portable IoT device, Li-ion is generally the better choice because of its higher energy density and longer lifespan. It’ll give you more runtime Per charge and is easier to manage in terms of charging circuits and protection. That said, Li-Po can work for IoT devices, but it’s usually overkill unless you have specific design constraints—like needing a really thin form factor or a custom shape that standard Li-ion cells don’t fit. One area where Li-Po might make sense is if your device has occasional power spikes, since Li-Po batteries can handle higher discharge rates.

Hi! I checked the circuit on TinkerCad. There were some mistakes, like wrong capacitor connection and value. Here's the edited one: A couple of points worth mentioning here: 1. On running the simulation, TinkerCad shows too much current drawn from the IC and may damage it. 2. This is true if you are running it continuously. In this case, all LEDs are ON at the same time for a very small duration, so it somehow works. 3. Still, not a good idea in the long run. I will suggest: 1. Use a 220-ohm resistor instead of 100. And connect two LEDs Per pin to only one resistor. Meaning a total of 8 resistors for an 8-pin. This will reduce the overall current draw from the IC and Per pin as well. 2. Better use 330 ohm..but not that it will reduce the brightness of the LEDs further.