Automatic 9V battery charger circuit diagram.
The circuit details are based on european standards: 120E, 150E, etc. The ‘E’ just stands for Ohms so 120 ohm, 150 ohm. The original circuit specified the HEF type of CMOS IC’s that are not readily on the market in most of worldwide country. So just get any other kind of CMOS chip like the MC4011, MC4020, MC4047 from Motorola. Any other type will work fine too. The BC548B is replaceble by a NTE123AP (NOTE: ensure it’s the ‘AP’ type, the typical NTE123A is a total different transistor), ECG123AP, and also the 2N3904 will be work. Watch for the proper pin locations because the BCE may be reversed with this european type. The LM317T is a TO-220 type and replaceble with a ECG956 or NTE956. The LM339N could be changed using a ECG834 or NTE834
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