This circuit is from a 1977 publication for radio amateurs presenting a crowbar protection. The transistor Q1 may be a BD136 and Q2 a 2N2955. The transistor and the integrated circuit must be equipped with good heat radiators. The transformer has 5 A of secondary. The indicator lamp can be replaced by a series LED with a 1k resistor.
This circuit is from a 1977 publication for radio amateurs presenting a crowbar protection. The transistor Q1 may be a BD136 and Q2 a 2N2955. The transistor and the integrated circuit must be equipped with good heat radiators. The transformer has 5 A of secondary. The indicator lamp can be replaced by a series LED with a 1k resistor.
