ˆ15. Install Q3 and Q4, 2N3904 NPN transistors, observing proper orientation of the flat side. These two transistors amplify the signal diode's output to a level high enough to close relay K1.

ˆ16. Install diode D4, 1N4002 style black epoxy diode. Check positioning of the banded end.

ˆ17. Install jumper JMP2. Use a piece of scrap component lead wire bent into a "staple" shape and inserted into the board like a component. Jumpers act as electronic "bridges" carrying signals over PC board circuit traces underneath.

ˆ18. Install C13, .1 µf disc capacitor (marked .1 or 104).

ˆ19. Install L4, 10 µH inductor (green body with brown-black-black bands).

ˆ20. Install R3, 10 K ohm resistor (brown-black-orange).

ˆ21. Install C2, 10 µf electrolytic capacitor. Electrolytic capacitors are polarized with a ( + ) and a ( - ) lead and must be installed correctly for proper operation. Generally, capacitors have their ( - ) lead marked with a black stripe while PC boards have the ( + ) hole indicated.

ˆ22. Install D1, 6.2 volt Zener diode (gray body with a black band). This diode provides a stable voltage which is used to provide bias for the power transistors.

ˆ23. Install R5, 1 K ohm resistor (brown-black-red).

ˆ24. Install R2, 6.8 K ohm resistor (blue-gray-red).

ˆ25. Install R1, 1 K ohm resistor (brown-black-red).

ˆ26. Locate another 1 K ohm resistor (brown-black-red). Trim back one lead to a length of ¼ inch. Bend this wire into a small loop as shown. This loop will act as a convenient point to connect a test probe for setting the bias voltage. Insert the resistor into the PC board and hold it carefully while you solder it to the board.

ˆ27. Install R8, 270 ohm resistor (red-violet-brown).

ˆ28. Install C11, .001 µf disc capacitor (marked .001 or 102).

ˆ29. Install R9, another 270 ohm resistor (red-violet-brown).

ˆ30. Install C12, another .001 µf disc capacitor (marked .001 or 102).

ˆ31. Install C8, .1 µf disc capacitor (marked .1 or 104).

QAMP20 • 8

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Ramsey Electronics QAMP20 manual
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QAMP20 specifications

The Ramsey Electronics QAMP20 is a versatile high-fidelity audio amplifier designed to meet the needs of audio enthusiasts and professionals alike. This compact amplifier is characterized by its exceptional sound quality, robust construction, and user-friendly features, making it suitable for a wide range of applications, from home theater systems to professional audio setups.

One of the standout features of the QAMP20 is its power output. With a maximum output of 20 watts per channel, the amplifier delivers clear and powerful sound, capable of driving a variety of speaker types with ease. The QAMP20 is particularly well-suited for small to medium-sized speakers, providing ample power to enhance the listening experience without distortion, even at higher volumes.

The QAMP20 employs advanced technology to ensure the best possible audio performance. It features a class AB amplifier design, known for its excellent linearity and low distortion. This technology strikes a balance between performance and efficiency, ensuring that users receive high-quality sound while minimizing power consumption. Furthermore, the unit utilizes high-grade components, including capacitors and transistors, which contribute to its overall durability and reliability.

In addition to its impressive audio performance, the QAMP20 boasts a user-friendly interface, making it easy to integrate into any audio setup. It includes multiple input options, allowing users to connect various audio sources, including CD players, computers, and digital music players. The rear panel features standard RCA inputs, while the front includes a 3.5 mm auxiliary jack, providing flexibility and convenience.

Another noteworthy aspect of the QAMP20 is its compact design. The amplifier is lightweight and small enough to fit seamlessly into most setups without taking up much space. This portability makes it an excellent choice for both home and on-the-go applications, allowing users to enjoy high-quality audio wherever they are.

In conclusion, the Ramsey Electronics QAMP20 stands out in the crowded market of audio amplifiers due to its combination of power, advanced technology, and user-centric design. With its ability to deliver exceptional sound quality and its flexible connectivity options, it represents an excellent investment for anyone looking to enhance their audio experience, whether at home or in a professional setting.
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