fixed voltage regulator

A heavy duty 13.8V regulated power supply is a fine thing to have in the shack, but unless you acquire one secondhand, is an expensive little beastie to buy. This means building one should be considered, not only for the cost savings, but also because you can brag about it on air to your mates. [...]

This electronic circuit is power supply that is a compact, easy to build and use positive variable power supply module. It is ideal for powering any application requiring a DC supply at current levels up to 1.5A.
Diodes D1-4 form a bridge rectifier which converts the AC input voltage into a DC level. They also allow [...]

The following power supply circuit uses LD1084#12 voltage regulator, which can provide up to 5Amps with only 1.3v dropout. Input voltage must be around 15v. It is highly recommended that you follow this value exactly, if the input voltage is more, the regulator temperature will increase more.
Calculation for the filtering capacitor:
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