This simple device will help with the help of ordinary hand drills to cut holes of any diameter in the plywood, hardboard and particleboard.
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THE TIMER CONTROLS THE SOUND
The device, whose scheme is published in the journal "Popular electronics" (USA), produces a positive pulse when a sound (for example, firing of the gun) reaches the microphone B1 (see...
STAIRS… KNOTS
Both in the construction and further operation or repair of individual or country house to work on the roof required a special ladder, better wood, with an l-shaped end at the top so you...
