BASIC QUESTIONS & PROBLEMS

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• Instead of the TIP120 Darlington that you specified, I built my own Darlington with two transistors.

• Instead of the 12-volt supply that you specified, I run my circuit off 18 volts.

• I proportioned all the resistors for another voltage. Why doesn't the circuit work well?

• The circuit doesn't respond properly to 1-volt video signals.

• The amplifier provides too much current or voltage for my display.

• Where do I connect the negative power supply?

ADVANCED QUESTIONS & PROBLEMS

• I want to use the LED driver with the line output of my CD player. How would I do that?

• I tested this circuit on a Spice simulator. For modeling purposes, I used a single LED, not the array. Linearity and frequency response are poor.

• I tested this circuit on a Spice simulator. I used "generic" transistor models, not the parts you prescribed. I see lots of nonlinearity.

• I tested this circuit on a Spice simulator. A "324" integrated front end would work better.

• This circuit inverts. Does the club video standard specify inverted video?

• This circuit provides too much gain. To fix that, you should add (or increase) an emitter resistor, etc...

• The input capacitor seems too small. Isn't that capacitor contrary to the idea of preserving the low frequencies?

• How might I improve this circuit?

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