This week we will also take our first test - the ohm's law / power formula Series and Parallel exercise.  All homeowrks and exercises must be handed in.  We will also begin soldering exercises, starting with making a simple clip lead, then on to making an XLR microphone cable. 

This week, you absolutely MUST be reading chapter's 5-8.  Next week we will learn Transformers and AC-to-DC conversion, A.K.A. R-E-C-T-F-I-E-R-S

3-Lamp Lab

This is a problem-solving lab.  The lamps have a cold resistance that can be directly measured and a hot resistance that must be indirectly measured.  Once again, we get to sharpen out multi-meter skills.



EQ networks

Week-3b: RECTIFICATION: Converts Alternating Current (AC) to Direct Current (DC) There are many ways to convert AC to DC as you will see on this page.  Each Rectifier type can be thought of as application-specific, some are for high current loads (like motors and power amps) and some for low current loads (like phantom power).  Keep in mind that the AC voltage is RMS, which is roughly 70% of the peak to peak value.  This is why the 'predicted' output voltage is stated as 'approximate,' because the efficiency is Load Dependent. 

Unloaded, the DC voltage out will be higher than the AC voltage in, because the AC voltage is stated in RMS terms, but without a load the peak of the sinewave charges teh capacitors, yielding a higher voltage. 

Zener diodes are used to regulate the voltage - to 'clamp' it so that it does not go higher than intended. 

FIGURE-1: Half-Wave Rectifier.  If the transofrmer supplies 10 voltsACrms, then the recitifed output will be approximately 10volts DC

FIGURE-2:  A simple voltage-doubler rectifier can derive two voltages from a single transformer winding.  Like the circuit above, 10-volts AC will yield approximately 10-volts DC, only now, with two diodes, there will be both plus and minus 10-volts DC that's two voltages referencing 'common,' which the symbol implies is also ground, or a single dose of  20-volt DC (from plus-to-minus, ignoring the common). 

FIGURE-3:  Full-Wave Rectifier

FIGURE-4: Full-Wave Bridge Rectifier

FIGURE-5: Bi-polar Full-Wave Bridge Rectifier