Power FET
Solder Connections

ˆ11. Install R1, 1K ohm [brown-black-red].

ˆ11. Install Q1, the power FET transistor [marked 7035]. Form the leads as shown prior to

installation. Bolt the

regulator to the circuit Tab board.

ˆ 12. Install L1, the large axial leaded wire wound inductor.

ˆ13. Install D1, 1N4937 fast

recovery diode. Observe the correct polarity! Note also that this is another “stand up” diode, so form the leads as before for a proper fit.

ˆ14. Identify Q2, a 2N3904 NPN transistor. When installing Q2, observe correct placement of the flat side. Press the transistor snugly into the PC board so that only a minimum amount of wire lead is exposed above the board. In soldering, do not be afraid of using enough heat to make a good solid connection.

ˆ15. Install R9, 1K ohm [brown-black-red].

That’s it for the switching high current supply! This part of the circuit provides the “muscle” to charge the batteries.

ˆ16. Install LED D3. This component is polarized and must be oriented correctly. Examine the LED and notice how one lead is longer than the other. Most diodes also have a flat mold in one side of the component body. This flat side is on the same side as the shorter leg. When properly installed, the flat side should face towards S2. Leave the diode leads as long as possible, because this component will mount to the front panel as a charging status indicator.

LED

(-) Leave these leads as long as possible

PC Board

(+)

ˆ17. Using scrap component lead, form a “jumper” wire and install it in the JMP2 position. A jumper acts as an electronic bridge to carry power and signal over the traces run underneath.

ˆ18. Form and install another jumper, JMP1.

ˆ19. Install R7, 470 ohm [yellow-violet-brown].

ˆ20. Install R12, 270 ohm [red-violet-brown].

ˆ21. Install R14, 17.8K ohm 1% [brown-violet-grey-red].

ˆ22. Install R16, 10K ohm 1% [brown-black-black-red].

DN1 • 13

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Ramsey Electronics DN1 manual Led
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DN1 specifications

Ramsey Electronics DN1 is a versatile and compact digital audio transmitter that caters to a variety of audio transmission needs. It is designed for hobbyists, educators, and DIY enthusiasts looking to create their own wireless audio systems. The DN1 offers a reliable solution for transmitting audio signals over short distances without the clutter of wires.

One of the main features of the DN1 is its ability to transmit audio in the FM band, which provides clear sound quality and minimizes interference. The device operates at a frequency range of 88 to 108 MHz, allowing users to choose the optimal frequency for their specific environment. This adaptability makes it suitable for applications like personal broadcasting, classrooms, or small events.

The DN1 is equipped with a simple-to-use interface, featuring adjustable audio input levels and an LED indicator for power and modulation status. It supports both mono and stereo audio inputs, making it a flexible option for various audio sources. Users can connect the transmitter to devices such as audio players, microphones, or computers, which allows for seamless integration into existing setups.

Another significant characteristic of the DN1 is its compact and lightweight design, making it easy to transport and mount in different locations. Its robust construction ensures durability, making it ideal for both indoor and outdoor use. This makes the DN1 an excellent choice for users who need a portable solution for DIY projects or presentations.

The device operates on a low-power consumption model, which is not only environmentally friendly but also cost-effective. It can be powered by a standard 9V battery or an external power supply, adding to its convenience and versatility.

In terms of performance, the DN1 boasts a transmission range of several hundred feet in optimal conditions, ensuring that audio signals remain strong and consistent even in larger areas. This range, combined with its ease of use, makes it an appealing option for those looking to broadcast audio without the limitations of wired connections.

Overall, Ramsey Electronics DN1 stands out as an innovative transmitter that brings together user-friendly features, excellent audio quality, and practical design. Whether for personal use, educational purposes, or event hosting, the DN1 meets the demands of modern audio transmission needs, allowing users to experiment and expand their audio capabilities with ease.
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