And just for the sake of completeness, here's the cct. of the earlier model, the 1220 / 1.
[attachment=6226]
Hint: Easier to read if it is opened in a new window: right-click the mouse.
Notice that us has a fat diode connected across its output as protection against the supply being connected to another supply but of reversed polarity. Also note that it features an adjustable crowbar cct.: the usual thyristor affair. The O/P has a 12-v. indicator lamp fitted, in series with a resistor. The output can be adjusted by the 4k7 variable resistor over a limited range: the 4k7 is in series with a fixed value of resistance to limit the adjustment range.
Al. / Nov. 16th., 2012 //
[attachment=6226]
Hint: Easier to read if it is opened in a new window: right-click the mouse.
Notice that us has a fat diode connected across its output as protection against the supply being connected to another supply but of reversed polarity. Also note that it features an adjustable crowbar cct.: the usual thyristor affair. The O/P has a 12-v. indicator lamp fitted, in series with a resistor. The output can be adjusted by the 4k7 variable resistor over a limited range: the 4k7 is in series with a fixed value of resistance to limit the adjustment range.
Al. / Nov. 16th., 2012 //
