Archive for July 2022

Electrical power in Greece

In Greece the standard mains power voltage is 230 V and frequency is 50 Hz. The power plugs and sockets are of type C and type F. I also saw some Type L (Italian) power oulets at hotel This is a somewhat strange looking extension cord. Thetr are somewhat strange looking outlets on this permanently

Mosquito trap teardown

I got few years ago this cheap USB powered mosquito trap. The idea in it is that Blue/UV light gets the mosquitos to go near the device, and then the device sucks them away. This product was cheap, but was not very effective. When I tried this device this summer, it did not seem to

Mosquito repellent tech

Mosquitos don’t just whine in your ear and drive you mad with itching, but they also spread disease to more than 700 million people every year. Mosquitoes are attracted to carbon dioxide as well as the warmth and humidity you’re giving off. There are many different types of mosquito repellent. From zappers to catchers to

Friday Fun: Absurd Trolley Problems

The trolley problem is a series of thought experiments in ethics and psychology, involving stylized ethical dilemmas of whether to sacrifice one person to save a larger number. Absurd Trolley Problems

Ethernet Network Domination

Venerable Ethernet provides the backbone of the internet. Ethernet has risen to complete dominance for local area networks over its forty years of existence. The first Ethernet experimentals versions started in 1972 (patented 1978). The commercialization of Ethernet started in 1980′s. At first Ethernet technology remained primarily focused on connecting up systems within a single

Old logic analyzer and probe cables

I got an old HP mixed signal oscilloscope HP54645D. This is over 20 years old test instrument with CRT display. The 54645D is a 100 MHz, 2+16 channel Mixed Signal Oscilloscope from Agilent. Measure voltage or current signals over time in an electronic circuit or component to display amplitude, frequency, rise time, etc. Applications include

Ethernet over coax – commercial converters

Nowadays it is possible to buy passive and active device to run Ethernet over Coax – some products support data transfer over larger distances then you can get on regular Cat5. The passive converters are typically limited to 100 Mbps maximum speeds up to 100-200 meters distance maximum. If you need faster speed or longer

Lithium charging security

Don’t do this! (There’s a much safer way) Big Clive discovered there’s a “thing” going around where people are charging lithium cells by attaching a stripped USB lead directly to them. Normally lithium cells are very safe if undamaged and correct charging procedures are used. But overcharging them like this can result in cell