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Matching Stages http://ww\v.talkingelectroni<x.com projects/ThePowerSupply/Page79 .

the power-rail is moving up-and-down at this frequency and becomes an ANTENNA! It begins to radiate electromagnetic waves and in the process becomes a HIGH IMPEDANCE linę.

In other words it becomes a high resistance linę and a voltage develops on it that opposes the 3v supply.

The current reduces and the Circuit does not get the required energy from the battery. This is equal to the power supply having a HIGH IMPEDANCE.

The impedance can be reduced by adding a capacitor across the power rails.

The performance of the following Circuit will improve:

By placing the 3v supply very close to the Circuit, the performance will increase enormously:

To keep the impedance of a power supply LOW, we need to:

(a)    Add an electrolytic - for low-frequency circuits,

(b)    Add a capacitor - for high-frequency circuits, and

(c)    keep the leads short.

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