The Simple Tech Behind Hidden Camera Detectors

If you’ve ever been concerned about privacy in a rental space or hotel room, you might have considered trying one of the many “spy camera detectors” sold online. In the video after break [Big Clive], tears one down and gives us  an in-depth look at how these gadgets actually work, and their limitations.

Most detector follow the same basic design: a ring of LEDs through which the user inspects a room, looking for reflections indicating a potential hidden camera. Although this device can help spot a camera, it’s not entirely foolproof. The work best when you’re close to the center of a camera’s field of view, and some other objects, like large LEDs can produce similar reflections

The model examined in this video takes things one step further by adding a disc of dichroic glass. Coated with a metallization layer close to the wavelength of the LEDs, it effectively acts a bandpass filter, reducing reflections from other light sources. [Big Clive] also does his customary reverse-engineering of the circuit, which is just a simple flasher powered by USB-C.

[Big Clive]’s teardowns are always an educational experience, like we’ve seen in his videos on LED bulb circuits and a fake CO2 sensor.

Continue reading “The Simple Tech Behind Hidden Camera Detectors”

An Unexpected Appearance Of An Iconic Motorola Chip

Big Clive's reverse-engineered schematic of the USB charger containing the MC34063 IC.
Big Clive’s reverse-engineered schematic of the USB charger containing the MC34063 IC.

Generally when you crack open a cheap car-to-USB charger unit that came with some widget, you do not expect to find anything amazing inside. That’s why it was such a surprise to [Big Clive] when said car USB charger revealed a blast from the past in the form of an MC34063. This is a switching regulator that supports buck, boost and inverting topologies, but perhaps it most notable feature is that it was first produced by Motorola in the early 1980s.

This particular IC is marked as having been produced by ON Semiconductor which means that it’s technically still manufactured by Motorola – with ON Semiconductor being the Phoenix division that was spun off in 1999 – but it’s somewhat remarkable that this particular chip isn’t only produced by ON Semi today, but also by Texas Instruments. Much like the venerable NE555 timer IC and Intel’s 8051 MCU architecture, it would seem that certain chips and designs are simply made to become commodities in the future.

This appears to be the case for the MC34063 as well, which may lack some niceties of more modern ICs, such as built-in thermal protection, and it switches at only up to 100 kHz, but it can be bought for peanuts, has a wide input voltage range of 3 to 40 V, can switch up to 1.5 A and supports multiple common topologies. Often a 100 kHz switching regulator is all you need, in which case it’s handy to have a stack of such commodity chips lying around, plus the MC34063 comes in PDIP packaging as well, which is a boon for prototyping.

Continue reading “An Unexpected Appearance Of An Iconic Motorola Chip”

Bug Clive goes into detail about electrical safety even at the most basic level of wearing gloves.

The Unofficial Guide To (Avoiding) Electrocution

If you’re reading this sentence, there’s a pretty good chance that you interact with electricity more than just as an end-user. You’re a hacker. You aren’t afraid of a few volts, and your projects may involve both DC and AC voltage. Depending on what you’re working on, you might even be dealing with several thousand volts. And it’s you who Big Clive made the video below the break for.

“Familiarity breeds contempt” as the old saying goes, and the more familiar we are with electronics, the more cavalier we may tend to get. If we allow ourselves to get too lax, we may be found working on live circuits, skimping on safety for the sake of convenience, or jokingly saying “safety third!” far too often as we tear into a hazardous situation without scoping it out first.

Who better to bring us down to earth than Big Clive. In this video, he explains how electricity has the potential to impede the beating of our hearts, the action of our lungs, and even break bones. You’ll find a candid discussion about what electric shock does to a person, how to avoid it, and how to help if someone near you suffers electric shock.

Of course, if safety isn’t your thing, then maybe you’re ready to Shake Hands With Danger.

Continue reading “The Unofficial Guide To (Avoiding) Electrocution”

Reverse Engineering Self-Powered Wireless Switches

The plethora of wireless communications technologies have cut the comms wire for many applications, but these devices still require power. For home automation, this might mean a battery or mains power, but there is also an alternative that we don’t see often: Kinetic power. [Bigclivecom] bought some kinetic switches from eBay and gave it his usual reverse engineering treatment.

True to the marketing, these switches do not require external power or a battery to send a wireless signal. Instead, it harvests energy from the magnetic latching action of the switch itself. When the switch is actuated, a small current is induced in a coil as the polarity of the magnetic field through its core changes rapidly. Through a series of diodes and resisters, the energy is stored in a capacitor, which is then used to power a small transmitter chip. The antenna coil is wrapped around the switch housing.

The receiver side is powered by mains and includes a relay output for lights. It would be really nice to have a hacker-friendly module for projects. We would be curious to see the range that these devices are capable of.

The same technology is used inside the Philips Hue Tap switch, of which Adafruit did a teardown a few years ago. If you want to learn more about RF modulation, check out the crash course article we put out a while back. Of course, the RTL SDR is an indispensable and affordable tool if you want to do some experimentation.

Continue reading “Reverse Engineering Self-Powered Wireless Switches”

Hacking A Cheap Disco Light For UV Effects

Back in the early days of disco, filament bulbs were all the rage. Whether tungsten, halogen, or other obscure types, party lighting involved lots of watts and lots of heat. These days, the efficiency of LEDs makes everything a lot cheaper, lighter, and lower power. [Big Clive] decided to dive into a cheap moonflower-type disco light from China, replacing the insides along the way.

The final effect particularly shines when used on fluorescent materials.

The light originally consisted of an 8×8 grid of LEDs, driven by shift registers for a simple chase effect. Surprisingly, the power supply and other hardware inside seemed to at least make an attempt to meet UK regulations. However, [Big Clive] had other plans, whipping up a replacement PCB packing 64 UV LEDs. The video is informative, showing how with a few simple passive components, it’s easy to drive these LEDs from mains without excessive circuitry required to step down to more usual DC voltages.

The final result is a neat UV grid light that would look excellent through some fog on the dance floor. We’ve seen [Big Clive]’s teardowns before, too – like this nefarious CAN bus interceptor found in a Mercedes. Video after the break.

Continue reading “Hacking A Cheap Disco Light For UV Effects”