TL;DR
A DIY alarm clock powered by an ESP32 triggers a relay to overload electrolytic capacitors, causing them to explode and wake the user. The project is experimental and not safe for home use. Its novelty highlights risks in unconventional electronics hacks.
An engineer has created an unconventional alarm clock that wakes users by causing electrolytic capacitors to explode through reverse voltage overload. The device, inspired by viral experiments, uses an ESP32 microcontroller to trigger a relay that applies reverse voltage to a capacitor, resulting in a loud explosion. This method, while effective at waking someone, raises serious safety concerns and is not recommended for home use.
The alarm clock is built around an ESP32 microcontroller that controls a relay. When the alarm triggers, the relay applies reverse voltage to a low-voltage electrolytic capacitor in a socket, causing it to violently rupture and produce an audible explosion. The project was inspired by a video from ElectroBoom and shared on Hackaday, emphasizing its entertainment value rather than safety.
According to Hackaday, this hack is highly unsafe and not suitable for DIY home projects. The explosion results from the capacitor’s venting mechanism, which varies between models. The creator explicitly states that this is a demonstration of what not to do, highlighting the dangers of mishandling electrical components.
The project has garnered attention for its novelty but also for its potential hazards, including electrical shock, fire risk, and injury from exploding components. Experts warn that such experiments should only be conducted with proper safety precautions and professional supervision, if at all.
Implications of Explosive Capacitor Alarm
This project underscores the importance of safety in electronics experimentation. While it demonstrates a creative, if dangerous, method to wake someone, it also highlights the risks of DIY hacks involving high-energy components. For the general public, it serves as a cautionary example of why such experiments should not be attempted at home, especially without proper safety measures.
From a broader perspective, the alarm clock’s design raises awareness about the dangers associated with electrolytic capacitors, which can vent or explode under incorrect voltage conditions. It also sparks discussions about the boundaries of DIY electronics and the need for safety standards in hobbyist projects.

LAFVIN Basic Starter Kit for ESP32 ESP-32S WiFi IoT Development Board with Tutorial Compatible with Arduino IDE
Perfect choice for beginners to learn, electronics and program.
As an affiliate, we earn on qualifying purchases.
As an affiliate, we earn on qualifying purchases.
Background on Exploding Capacitor Projects
Electrolytic capacitors are common electronic components used for energy storage. They are designed with safety vents to release pressure if they overheat or are subjected to incorrect voltage. The recent trend of exploding capacitors for entertainment or shock value has appeared in various hobbyist videos, often inspired by viral experiments like those from ElectroBoom.
This particular project, shared via Hackaday, builds on this fascination but emphasizes its impracticality and danger. Historically, such experiments have been used to demonstrate capacitor characteristics but rarely as a practical or safe wake-up method. Experts have repeatedly warned against attempting such modifications outside controlled environments.
The project’s popularity stems from its shock factor, but safety advocates caution that these are dangerous stunts that can cause injury or damage.
“This kind of experiment is extremely unsafe and should never be replicated at home. The risks far outweigh any novelty value.”
— an anonymous researcher

Velleman Atlas ESR70 Capacitance and ESR Meter
Measure capacitance and ESR
As an affiliate, we earn on qualifying purchases.
As an affiliate, we earn on qualifying purchases.
Safety and Practicality of Explosive Alarm Clocks
It remains unclear whether the creator intends to develop safer versions or if this was purely a one-off experiment. No official safety guidelines or plans for commercial use have been announced. The long-term safety implications and legal considerations of such devices are not yet established.

ELEGOO 4 Channel DC 5V Relay Module with Optocoupler Compatible with Arduino UNO R3 MEGA 2560 DSP ARM PIC AVR STM32
This relay module is 5V active low. Relay output maximum contact is AC250V 10A and DC30V 10A.
As an affiliate, we earn on qualifying purchases.
As an affiliate, we earn on qualifying purchases.
Future of Unconventional Alarm Technologies
Experts and hobbyists are likely to continue exploring creative alarm mechanisms, but with increased emphasis on safety. Regulatory bodies may also issue warnings or restrictions on hazardous DIY experiments involving high-energy components. For now, the focus remains on raising awareness about the dangers of unsafe electronics hacking.

ELEGOO Mega R3 Project The Most Complete Ultimate Starter Kit with Tutorial Compatible with Arduino IDE
The ELEGOO MEGA2560 complete starter kit includes over 200pcs premium components, and is compatible with Arduino kits
As an affiliate, we earn on qualifying purchases.
As an affiliate, we earn on qualifying purchases.
Key Questions
Is this alarm clock safe to build or use?
No. The device involves exploding electrolytic capacitors, which can cause injury, fire, or damage. It is strongly discouraged to attempt building or using such a device at home.
Why would someone create an alarm that explodes capacitors?
Primarily for entertainment or shock value, demonstrating a dramatic way to wake up. It is not intended as a practical or safe solution.
Are there safer alternatives to unconventional alarm clocks?
Yes. Conventional alarm clocks, vibrating alarms, or smart device alarms are safe and effective options for waking up.
Could this project cause legal issues?
Potentially. Using or distributing devices that intentionally cause damage or pose safety hazards could violate safety regulations or laws, depending on jurisdiction.
What lessons can hobbyists learn from this project?
It highlights the importance of safety, proper handling of electrical components, and understanding the risks involved in DIY electronics experiments.
Source: Hackaday