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Ramsey Electronics QRP20 manual WHO should USE a QRP TRANSMITTER?, Circuit Description

Models: QRP20

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On the other hand, if you hear a 1000 watt station producing a moderate signal such as S4 or S5, you can reasonably assume that you will not have a lot of luck over that path right now with the theoretical S1 signal level of your QRP transmitter.

While these figures also can be used to show how nice it is to have a power amplifier and beam antenna, they indeed serve to show that reasonable signal levels indeed are achievable with low power and a dipole antenna.

"QRP" enthusiasts have their own rituals, jargon, strategies, QRP operating contests, magazine columns and books, and convention get-togethers. They constitute a vital segment of the amateur radio community, because they consistently demonstrate the feasibility of low-power communication. In fact, the most avid QRP enthusiasts would not regard communication with a Ramsey transmitter especially challenging, since they prefer the new world of milliwatt operation, known as "QRPp"! And, yes, the ones who have conquered the "milliwatt" world ARE setting records with "milliwatt" tests. With the world record set in 1970 between Alaska and Oregon on ONE microwatt, think about it this way: your Ramsey QRP transmitter is almost one million times more powerful than the transmitter used in that historic test!

WHO SHOULD USE A "QRP" TRANSMITTER?

There is a philosophy that "Novices" should not get started with a very low power transmitter. The reasoning is that most newly-licensed amateurs need to build up the confidence that comes with actually making contacts and that they do not need the additional challenge and pressure of low-power operation. There is some wisdom in this view, but that opinion should not make newcomers apprehensive about trying a Ramsey QRP transmitter, IF:

1.This is where your budget is.

2.You can count on somebody to help you with assembly.

3.You can count on somebody to listen to your signal during initial tests.

4.You have a reasonably good receiver.

5.You have space for a normal, no-compromise antenna for the band you wish to operate, either a standard dipole, or the "inverted V" dipole, or quarter-wave vertical.

CIRCUIT DESCRIPTION:

In brief, Q1 is a crystal oscillator, amplified by buffer stage Q2, which drives Q3 as the RF output amplifier. Q4 is a PNP keying circuit which opens and closes the 12VDC supply line to Q1 and the T-R circuitry of D1 and D2.

S1 selects either of two crystals. R1,D3,D4 and L1 form a varactor controlled series resonant circuit with the crystal. Adjusting R1 permits a crystal frequency swing of up to 7 KHz, about the crystal frequency.

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Ramsey Electronics QRP20 manual WHO should USE a QRP TRANSMITTER?, Circuit Description
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QRP20 specifications

The Ramsey Electronics QRP20 is a compact and innovative low-power transceiver designed for amateur radio enthusiasts who appreciate both portability and efficiency in their operations. This QRP (low power) radio is primarily aimed at those who seek to operate on the HF bands, providing an exhilarating experience for operators who thrive on the challenges and satisfaction of making contacts with minimal power output.

One of the standout features of the QRP20 is its compact design. This radio can easily fit into a backpack, making it ideal for field operation, portable use, or emergency communication scenarios. Weighing in at just a few pounds, it’s lightweight enough for extended outings without burdening the operator.

The QRP20 operates on a range of HF bands, specifically covering 20 meters, which is especially popular among amateur radio operators for its relatively consistent propagation and activity level. The transceiver leverages solid-state technology, ensuring reliability and optimizing performance. It can produce an output of up to 5 watts, which is standard for QRP operations, allowing operators to experiment with different antenna configurations and propagation techniques.

Another significant aspect of the QRP20 is its user-friendly interface. The radio features a straightforward layout with well-placed knobs and buttons for efficient tuning and operation. The built-in digital display provides clear visibility of frequency information and operational status, enhancing the overall user experience. In addition, the QRP20 includes a narrow bandwidth filter, which effectively reduces noise and enhances signal clarity, enabling clearer communication even in crowded band conditions.

The QRP20 is equipped with an internal speaker as well as a headphone jack for private listening. It also features a built-in keyer for CW (Continuous Wave) operation, making it versatile for various modes of amateur communication including voice and Morse code.

Powering the QRP20 is effortless, as it can be run off a standard 12V power supply or a rechargeable battery, giving operators flexibility in power sourcing. Whether during portable activations or in a home setup, the QRP20 is adaptable to different operating situations.

In conclusion, the Ramsey Electronics QRP20 is a remarkable choice for amateur radio users who value portability, versatility, and performance. Its efficient design, solid technology, and ease of use make it a compelling addition to any operator's gear, offering a satisfying QRP experience while staying connected with a global community of radio enthusiasts.