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Stages hUp/Ał-w^talkingelectronicscomprojecb:

This is the same as the output raił of a power supply. When the electrolytic is added, the raił does not move up and down. The electrolytic also adds to the ability of a power supply to deliver a high current. It is really an amazing component.

If a power supply cannot deliver a high current, the voltage on the output will drop and this can cause distortion or faulty operation of the rest of the project.

THE SIMPLEST POWER SUPPLY

The simplest power supply is a celi or battery. A cells is either 1,5v (or 3v). A battery is a number of cells.

The term IMPEDANCE still applies and the CURRENT PATH is though the celi or battery.

The current path

The current path

A new celi or battery has a Iow impedance as proven by its ability to deliver a high current.

As the battery gets older, the voltage across its terminals reduces and the maximum current it can deliver also reduces.

The reason is the active Chemicals get used up, and the resistance of the by-products is higher.

Ali projects work perfectly with a new battery, but unless you remember some simple rules for correct designing, a new battery can still cause problems.

When deigning high frequency projects such as 100MHz "bugs" or FM transmitters, the leads to the battery must be as short as possible to keep the impedance of the power supply LOW.

Here is an example:

This FM transmitter Circuit does not work:

The 3v supply is too far from the Circuit. The Circuit is operating at approx 100MHz and