This type of eye fatigue or eye strain is sometimes known as computer vision syndrome. It affects about 50%-90% of computer workers. Some estimates say computer-related eye symptoms may be responsible for up to 10 million primary care eye examinations each year.
MAST MOUNTED PREAMPLIFIERS. Chapter Eight-TV ANTENNA-MOUNTED AMPLIFIERS. A mast or TV antenna-mounted amplifier (preamp) is used primarily to eliminate snow on the TV screen.Snow is actually electrical noise that is generated by the TV receiver and other electrical devices.he preamp itself is mounted on the TV antenna boom or on the mast as close to the TV antenna as possible. The power supply unit is mounted indoors. Power is supplied to the preamp unit through the transmission line.
There are basically two types of amplified TV antennas. The first type most referred to as an amplified TV antenna are those antennas with the antenna amplifier built into the antenna housing. Usually the built-in preamplifier is hidden inside of the antenna plastic housing and you can't see it.