AC/DC POWER SUPPLY KIT MODEL K-11 Assembly and Instruction Manual ELENCO ® Copyright © 2014, 1989 by ELENCO® All rights reserved. Revised 2014 REV-N No part of this book shall be reproduced by any means; electronic, photocopying, or otherwise without written permission from the publisher.
PARTS LIST If you are a student, and any parts are missing or damaged, please see instructor or bookstore. If you purchased this AC/DC power supply kit from a distributor, catalog, etc., please contact ELENCO® (address/phone/e-mail is at the back of this manual) for additional assistance, if needed. DO NOT contact your place of purchase as they will not be able to help you. RESISTORS Qty. r 1 r 1 r 1 Symbol R1 R3 R2 Value 1kΩ 5% 1/4W 2.7kΩ 5% 1/4W 10kΩ Potentiometer Qty.
INTRODUCTION The electrical power that is supplied by your power company is what is known as Alternating Current or AC. This current is constantly changing amplitude and polarity (see Figure 1). The electrons (current) move back and forth at a rate of 60 times per second. This type of current is not suitable for most electronic circuits. It must be converted into a Direct Current or DC which moves in one direction only. Your MultiPurpose Power Supply does exactly that. It converts AC into DC.
FILTERING used in our power supply. The DC filter output voltage will vary between 18 minimum and a higher voltage, depending on load current. The voltage across the zener diode will remain constant at 17V. This constant voltage is important to control the output of the regulators as 18V min. 17V Filtered Output you will see in Reference Voltage at C1 Voltage the following R1 section. D8 Filtering is the process of smoothing out AC hills produced by the full wave rectifiers.
CONSTRUCTION ● Turn off iron when not in use or reduce temperature setting when using a soldering station. Introduction The most important factor in assembling your K-11 Power Supply Kit is good soldering techniques. Using the proper soldering iron is of prime importance. A small pencil type soldering iron of 25 watts is recommended. The tip of the iron must be kept clean at all times and well-tinned. ● Tips should be cleaned frequently to remove oxidation before it becomes impossible to remove.
ASSEMBLE COMPONENTS TO THE PC BOARD T1 - Transformer, two 6-32 x 5/16” Screws, two 6-32 Nuts, Shrink Tubing, Cable Clamp, & Line Cord 1” Shrink Tubing Line Cord Red Transformer Wires Cut the shrink tubing into two 1” sections. Slip a section of tubing onto each of the two lead wires on the line cord. Twist each of the two wires on the line cord with the two black wires from the transformer. Solder these wires. Slide the shrink tubing down over both black wires to cover the solder joints.
OPERATING PROCEDURE To operate the K-11 Power Supply, plug the line cord into a 120V, 60Hz AC outlet, turn the switch (S1) to the ON position and rotate the potentiometer (R2) to make the output voltage climb from 0 to 15 volts DC. The red wire from P1 is the positive output, the blue wire from P2 is the negative DC output, and the two yellow wires are the AC output - 8.5V without regulation. Output AC OUTPUT Positive DC: 0-15V @ 250mA AC: 8.
QUIZ Mark the box next to the letter with the correct answer. 1. AC voltage is supplied to the rectifier stages by the . . . r A. step-up transformer. r B. step-down transformer. r C. 1-to-1 transformer. r D. AC-to-DC transformer. 2. The secondary windings of the transformer are . . . r A. 90O out of phase. r B. 180O out of phase. r C. 270O out of phase. r D. 320O out of phase. 3. Diodes allow current to flow . . . r A. when the anode is more negative than the cathode. r B.
