There are numerous ways to make current, to the ball of yarn did not run away and not out somewhere. The easiest is to put it in a box, basket, or, as shown in the drawing, just the right size jar.
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PLUG ALARM
I've been familiar with the "Modelist-Konstruktor" magazine for more than a year now. Mainly as an avid reader and somewhat less as a DIY enthusiast, trying to implement in practice some...
FOR BIPOLAR TRANSISTORS
This device whose description was published in the journal "Funkamateur" (GDR), used in various measuring devices or equipment, where necessary intermittent light or sound alarm....
