All you need to know about Linear PSU (Power Supplies) To Build And Fix Stuff – Tutorial Guide
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Let’s take a look at Linear Power Supplies. These are much simpler than Switch Mode PSU but there is still plenty to learn, We’ll put together a small dual positive/negative power supply mostly using parts salvaged from a NiCAD/NIMH battery charger. Of course things don’t quite go to plan and it doesn’t work! So we have to diagnose and fix the problem. There is some very good advice about the fundamentals of Electronics Repair here – watch it through and you may have a ‘light bulb’ moment!
CHAPTERS
00:00:00 Prologue
00:02:08 The Battery Chargers
00:07:31 Salvaging The Components
00:27:40 Schematic (Pt 1)
00:32:13 Connecting The Transformer
00:33:24 DANGER! Autotransformers
00:37:01 Rectifier Diodes
00:40:29 Half Wave Rectification
00:42:23 Schottky Diodes
00:46:44 Schematic (Pt 2)
00:48:52 Smoothing Capacitors
00:52:08 Schematic (Pt 3)
00:55:08 Voltage Regulators
00:56:20 It Doesn’t Work!
00:57:05 Diagnosis
00:59:05 *** THE IMPORTANCE OF IMPEDANCE ***
01:05:25 Fault Finding (Pt 1)
01:06:50 Ohms Law
01:09:14 Fault Finding (Pt 2)
01:18:00 Load Testing
01:23:08 Full Wave Rectification
01:31:41 Battery Chargers (Reprise)
01:38:01 Epilogue
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