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RE: Motor driver not working properly

Admin — Fri, 06 Mar 2026 05:24:06 +0000

@noochee Can you please share more details? Circuit diagram, connection photos, code etc.

Motor driver not working properly

Noochee — Fri, 20 Feb 2026 22:50:49 +0000

I built an obstacle avoiding robotic car using Arduino, dc motors and a motor driver(L293D) , ultrasonic sensor and servo, i added LCD, a buzzer, an LED and a bluetooth module, but it's getting overloaded i guess and it doesn't work, what do i do?

Answer to: Bluetooth Speaker won't turn on

servitec — Tue, 20 Jan 2026 07:01:40 +0000

Sorry, this is the second pic

Side-B.jpg

Bluetooth Speaker won't turn on

servitec — Tue, 20 Jan 2026 07:00:52 +0000

I know is not probably the best place for a newbie, the AI somehow helps but I definitely prefer go with the experts. I am fascinated with the laws of electronic, but more than ever I know it demands a serious compromise to enter this amazing world.

Board Description: HXYT-A0-665-REV1.1 (A bluetooth speaker)
The speaker wont turn on, is doing nothing.
SIDE A
Compt.1= 56HS5, B310B (5 pins)
Compt.2= J6 (3 pins) ?
Compt.3 4004A, 33580KM
Side B
Compt.1= 4R7 (inductor)
Compt.2= SS54 (SCHOTTKY BARRIER RECTIFIER)
Compt.3= M8889, Y4D371 (8 Pins) ?
Compt.4 PNSA15E7E, X0B253, 2359

--When connected the battery in the terminals, it shows normal (aprox 5V)
--I tested the negative and positive spots in reverse of battery connector and off course no shorted
--When first tested pin C of power button, it shows 0.840V, after some tests is showing 2.4V when first push the power button it drops to 0V but now no more drops and it gets 2.4 V no matter if push the power button
--Tested all capacitors of Side A and all of them are ok, also the capacitor X which is connected to the Compt.3, the component 3 seems to be a DC-DC converter, the capacitor X is in parallel of pins 4 and 6. When checking the VIN in Compt.3 (pin5) is ok, but when I push the power button there is no VOUT (pin1)
--When connected to the charger, the device’s charging led turns on and the board battery terminals shows the charging voltage.

In Side B

We can see the battery port, the left pin is the + one, that pin goes to the compt.1 through pad named in the image as “pad positive pin”, then the compt.1 is connected to the compt.2 (I tested both and they seem to be ok). I tested all capacitors in Side B, all of them are ok except capacitor X. The capacitor X is connected to the pin that is marked with a yellow face sticker in compt.4, and I'd like to have the PCB's information or at least the compt.4's (or the M8889) in order to know that capacitor values.
What more testing do you recommend me to apply, what is component 2 in side A, what is component 4 in side B, is it a multiplexer? What is component 3 in side B, is it a switch IC? What recommendations can you give me when is hard to find a component by its code?

Side-A.jpg

Answer to: Why Fluke multimeters are so expensive?

maryjlee — Sat, 08 Nov 2025 11:29:40 +0000

Totally agree with the points above. In my experience, the premium price of Fluke multimeters comes down to real reliability and safety engineering, not just branding. These devices are built for professionals working in hazardous environments: high-energy mains, industrial settings, etc.

Tough housing, drop-tests, high-CAT safety ratings.
High accuracy, true-RMS, stable calibration.
Long lifespan, support and warranty which reduce long-term cost.

If you’re replacing a hobby-meter and don’t work in heavy duty applications, yes you might be fine with a cheaper brand. But if you need one tool that you can trust under serious conditions, the extra cost makes sense.

Answer to: Can Raspberry Pi Replace a Home Router or Firewall?

Divyam — Thu, 30 Oct 2025 05:17:50 +0000

Yes, it’s definitely possible to turn a Raspberry Pi (especially Pi 4 or Pi 5) into a router or firewall using software like OpenWRT, Pi-hole, or pfSense (via ARM builds).

The Pi 4/5’s Gigabit Ethernet and USB 3.0 ports allow decent throughput—around 600–900 Mbps in real-world tests—suitable for small to medium networks.

However, it lacks hardware NAT acceleration and enterprise-grade security features, so performance may drop under heavy traffic or multiple VPN connections.

For basic routing, ad-blocking, and light firewall duties, it’s reliable and stable; for high-load or mission-critical use, a dedicated router or firewall appliance is still preferable.

Answer to: How can I safely power a BLDC motor from a hard disk drive?

Divyam — Thu, 30 Oct 2025 05:13:19 +0000

Use a small sensorless 3‑phase BLDC driver board (made for fans/HDDs) and power it from a current‑limited supply; start at 3–5 V with about 0.5–1 A limit (1–2 A for 3.5″ motors) and only increase if needed—don’t jump straight to 12 V.

An RC sensorless ESC with a servo tester can work but may be difficult; a microcontroller + driver is great for learning but not the easiest.

To find the pinout, measure resistance with a multimeter: with 3 wires, all pairwise readings should match (the three phases); with 4 wires, the pin that reads the same to all others is the neutral; phase order only affects direction, so swap any two leads to reverse.

To avoid damage, never apply DC across two leads, don’t stall the rotor, keep leads short (with a decoupling capacitor near the driver), and watch temperature.

Answer to: Why Fluke multimeters are so expensive?

Kanishk — Tue, 28 Oct 2025 05:39:05 +0000

Fluke meters are pricey because they’re engineered for people working around high‑energy mains who need gear that’s safe, accurate, and durable.

You’re paying for true CAT III/CAT IV protection with independent certification, high‑rupture fuses, proper creepage/clearance, robust housings and leads, stable True‑RMS accuracy, and features like LoZ, VFD filtering, and fast continuity.

Add tight QC, long warranties, service/parts availability, and strong resale/calibration support, and the cost reflects safety engineering and longevity more than branding.

How can I safely power a BLDC motor from a hard disk drive?

Anil_Tech — Tue, 28 Oct 2025 05:32:49 +0000

I have a brushless DC motor taken from an old hard disk drive and I want to power it safely for testing or small DIY applications. Since these motors are usually designed for specific control circuits, I’m not sure about the correct voltage, current, and driving method.

What’s the safest way to power and control a hard drive BLDC motor?

Should I use a dedicated ESC, a custom driver circuit, or a microcontroller-based solution?
Any tips for determining the correct pinout and avoiding damage to the motor would also be helpful.

Answer to: How can I interface an AI camera module with Arduino?

cooper — Mon, 27 Oct 2025 06:36:10 +0000

Arduino Uno and Nano primarily function as control interfaces rather than image processors when working with AI camera modules.

These boards have extremely limited resources (2KB RAM on Uno, 32KB flash memory) which makes it impossible to store even a single 320x240 pixel image, let alone process it. Instead, AI modules like HuskyLens, OpenMV, or ESP32-CAM contain dedicated processors (like STM32H7 in OpenMV or ESP32 in ESP32-CAM) that handle all the computationally intensive tasks internally.

These modules run neural networks, perform image processing, and extract features, then send only the interpreted results to Arduino - such as "face ID:1 detected at position (150, 120)" or "red line detected at angle 45°".

The Arduino then uses these simplified data packets to make decisions, like turning a servo to track the face or adjusting motor speed to follow a line.