I, like many hams-designers in recent times dealing with electronic devices, focusing on powered by the vehicle electrical system. It is a powerful receiver and radio stations, and also special electronic systems. Such devices consume a current of about 3 And, therefore, during their operation in stationary conditions, the problem arises to block power.
To solve it helped me rectifier WU - 1" Ulyanovsk instrument-making plant, intended for charging car rechargeable batteries. The fact that WU - 1" is essentially half of my desired device. It has enough power (up to 100W). Can only add to its stabilizing attachment for a voltage of 12V when currents up to 6 A.
Console (see diagram) is made according to the classical scheme of the voltage regulator from non-deficient parts of the low cost. The work of the composite transistor VT1 controls the DC amplifier transistor VT2: its emitter connected to the reference voltage source consisting of a Zener diode VD1 and the resistor R2, and the base - to the measuring circuit R3R4. Resistor R1 is used to supply bias the base of transistor VT1. Resistor R4 sets the desired output the tension.
Capacitors C4 and C5 prevents the excitation of the stabilizer at a high frequency, and C1 - C3 form a filter, a smoothing output voltage ripple WU - 1".
Details consoles mounted on the PCB from any foil material. Traces of high-current circuits shall be a minimum width of 10 mm and well tinned. The cross-sectional area of connecting wires is not less than 2 mm2.
All fixed resistors - MLT, trimpot R4 may be of any type. Capacitors C1 - C3 and C5 - C50-35 or K50-24 (I used oxide capacitors foreign production companies UPTRON and HONSING), the capacitor C4 is any non-polar. Powerful transistor VT1 is mounted on a heat sink, designed for power dissipation at least 60 watts.
The circuit Board device can be mounted directly on insulated from housing heat sink transistor VT1.
The establishment of consoles comes down to setting a trimming resistor R4 of the output voltage 12 V.
For stabilizing the prefix in the nominal mode switch S1 WU - 1" should be "More".
The capacitor C4 is better to include between the base of transistor VT1 and General wire.
Author: A. Sokolov, Dimitrovgrad, Ulyanovsk region