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Ramsey Electronics Model No. MX-5 Now here’s the simple easy to use mixer for all of you home brew DJs out there! This mixer has two line inputs and one microphone so that you can hook up all of your audio sources to any transmitter or audio amplifier.
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COPYRIGHT 1996 by Ramsey Electronics, Inc. 793 Canning Parkway, Victor, New York 14564. All rights reserved. No portion of this publication may be copied or duplicated without the written permission of Ramsey Electronics, Inc. Printed in the United States of America. MX-5 Page 2...
Schematic Diagram ...... 12 Setup And Testing ....... 16 Troubleshooting ......17 Parts Value Diagram ....18 Parts Layout Diagram ....19 Using the MX-5 ......21 RAMSEY ELECTRONICS, INC. 793 Canning Parkway Victor, New York 14564 Phone (716) 924-4560...
CD player and a tape deck. The MX-5 does not have any tonal controls for each channel, but almost all users of this project will want a flat response anyhow. If they do not, they will run the output of the mixer directly into an equalizer to custom-tailor their sound.
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MX-5 CIRCUIT DESCRIPTION We will use the schematic diagram to step through the circuit and find out what makes it “tick”. As you can see, there is only one IC in the entire circuit, but there are four individual operational amplifiers in the one IC. U1:A and U1:B are the main components of the mixer.
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The output from the microphone amplifier is then mixed in with the line level audio as well. Before exiting the MX-5 though, the output of U1:A and U1:B is controlled by the master level control, R6. The power supply for the MX-5 is simple enough, it consists of a 9-18VDC input or battery, and a voltage divider to provide for a split supply.
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(1). The part is then soldered securely to the board (2-4), and the remaining lead length is then clipped off (5). Notice how the solder joint looks on close up, clean and smooth with no holes or sharp points (6). MX-5 Page 7...
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If a problem does occur, the manual will lead you through step by step in the troubleshooting guide until you find the problem and are able to correct it. MX-5 Page 8...
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ASSEMBLY OF THE MX-5 Now we are getting to the good stuff-assembling the MX-5. We will begin by mounting first the low parts, beginning with the parts on the side of the board without the traces. When we are finished with that side, we will begin to install parts on the trace side of the board.
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We will be installing many more of these later in the project so be sure and remember this! 29. Install C4, a 10uF electrolytic capacitor. Again note polarity! 30. Install C2, another 10uF electrolytic capacitor. MX-5 Page 11...
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41. Install D3, a 1N4002 type diode (black body with white stripe on one end). This diode prevents you from inadvertently connecting external power to the MX-5 while there is a battery installed, and trying to recharge a battery. If this diode wasn’t there, you would very quickly have a ruined kit.
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Make sure and solder all four mounting lugs as well as the two pairs of connections on each end. Then flip the board over and solder MX-5 Page 13...
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Then check for cold solder joints and possible solder bridges. INITIAL TESTING THE MX-5 For this portion of the kit building experience you will need the following items: Line level source such as a tape deck, signal generator or CD player.
MAIN is turned up full. SOLUTION: Because the MX-5 has some gain, you will either need to keep the MAIN adjustment from going all the way to full, or you can open the FM- 10A or FM-25, and adjust the controls for level on their inputs.
Above shows a full installation for radio broadcasting using one of the Ramsey micropower transmitters. The parts and pieces are as follows: MX-5, our newly built mixer PH-15, Peak hold meter for watching audio levels STC-1, Stereo transmitter companion. Compression, limiting, bass, midrange, and treble controls.
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Give us a buzz, well send you a catalog. Call or write: Ramsey Electronics 793 Canning Pkwy. Victor, NY 14564 PH# (716) 924-4560 FAX# (716) 924-4555 MX-5 Page 20...
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But on rare occasions a sour component can slip through. All our kit parts carry the Ramsey Electronics Warranty that they are free from defects for a full ninety (90) days from the date of purchase. Defective parts will be replaced promptly at our expense. If you suspect any part to be defective, please mail it to our factory for testing and replacement.
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MX-5 STEREO THREE CHANNEL MIXER KIT Quick Reference Page Guide Introduction .......... 4 How Does It Work? ......5 Learn As You Build ......7 Parts List ..........9 Construction ........10 Schematic Diagram ......12 Setup And Testing ......16 Troubleshooting .........