Audio and Video

HDMI cable EMC failures

It seems that he quality of video cables sold in EU should be much better than it is now. I am not talking about mechanical strength or ability to transfer signal through, but the electromagnetic compatibility. The Swedish Electrical Safety Agency, together with other authorities within the EU, has tested HDMI and antenna cables. EMC


SDI is a one-way, multiplexed protocol designed to carry the highest quality video, audio and metadata over a coaxial cable or fiber. SDI is a professional video signal that is preferred in production environments because of its longer range (up to 300 feet) and reliability. If you’re in an environment in which your cable could

XLR Mic cable tester with one LED

Here is my newest build: Microphone wiring tester. This tester will turn on LED when microphone wiring is OK and phantom power is turned on. If there is any common problem, LED will stay off. This circuit will detect ground connected to wrong pin, broken wires that make no contact and short circuit between wires.

SH-666 microphone

The microphone of the beast? Depends on the culture. We’ve all heard about the infamous number 666, which is rather cryptically referred to as the “number of the beast” in the New Testament, and has more recently become known as the number of the Antichrist. In the Bible, 666 is also the number of talents

Behringer CT100 look inside

Behringer Cable Tester CT100 is a pretty nice and cheap cable tester for all kinds of audio cables.The CT100 accepts many type of cable you might use in a recording or live performance situation: XLR, mono and TRS phone (¼”, 1⁄8″, TT), RCA and even MIDI. here are three operating modes: Cable Test, installed Cable

Faked telephone ring tone

The Western Electric Model 500 and its subsequent variants were so ubiquitous that you almost couldn’t go anywhere without seeing one, especially in the United States. You have seen and heard this literal fixture of American life phone on countless of TV series and movies. Unfortunately many producers have been a little lazy and did

PA amplifier rack

Building a sound system is often a highly personal process, from deciding what to get, to assembling and using it. Here is my PA system I built in 1990′s and used for some mobile DJing. The need for measurements were that it should fit easily to a normal size car with everything else that is

Antenna isolator teardown

A ground loop in your AV system caused by antenna connection or TV cable is very common if you have your computer connected to the same system. This type of ground loop problem can be solved by using suitable isolator between your AV system and the antenna cable. Antenna isolator is very convient way to