Ramsey Electronics QRP20 manual Introduction

Page 4

INTRODUCTION:

Most "QRP" transmitters are one-of-a-kind experimental circuits which take some patience and fine-tuning to get clean keying and satisfactory performance. Most QRP building projects presume either unlimited radio junkboxes with all the right coils and capacitors, or that you have a lot of time on your hands to track down needed parts. And that is part of what ham radio can be all about. The purpose of the Ramsey Electronics series of QRP transmitters is to give our amateur radio customers the option of picking up a truly complete and reliable transmitter kit for whenever you need a compact CW rig for a particular opportunity, perhaps a camping or business trip or a weekend contest, or something economical to share with a favorite new Novice.

This transmitter is a serious and practical device for radio amateurs with general interests, as well as for QRP enthusiasts.

NOTE TO NEWCOMERS: "QRP" is amateur radio shorthand referring to operation at "reduced power". As a standard "QRP20-signal", the CW expression "QRP?" really means all of this: "If you are receiving me so well, and since the FCC requires that we use minimum power necessary to maintain useful communication, do you think I should reduce transmitting power?" The act of reducing power output can be the switching off of a linear power amplifier, or switching from 25 to 5 watts on your new Radio Shack 10 meter rig or turning back the carrier level control on most modern transceivers. For equipment description and contest competition purposes, "QRP" refers to transmitter powers under 5 watts.

In our manuals for the Ramsey Amateur Band receivers for the 80 and 40 meter bands, which tend to be of interest to many beginners because of available Novice and Technician operating privileges, we try to be very basic and patient, hoping that such an approach will be helpful to radio newcomers - as well as to casual, licensed amateurs who just did not know that worthwhile radio gear could be constructed at Ramsey's low prices, even in the 1990's.

Talking through a transmitter project presents a different challenge. Talking through a multi-stage transmitter that delivers a grand total of one or two watts to your antenna is an even greater challenge. In these times when a "barefoot rig" is assumed to be an imported, digitally-synthesized transceiver putting out over 100 watts at a cost of $1000-2000.00, we need a sensible and helpful way of talking about this QRP transmitter you are about to construct.

It's easy to prove that Ramsey's popular and economical receivers work just fine. Build one right, turn it on, and we become easily convinced. A transmitter is a different story, especially a transmitter that runs low QRP power! Different from a receiver, you want to see some measurable output power and you especially want to make two-way contacts!

QRP-20 • 4

Page 3 Page 5
Image 4
Page 3 Page 5
Contents CW Transmitter Ramsey Transmitter Kits QRP20 20 Meter CW Transmitter KIT Introduction Watts vs 1 Watt Understanding the Difference QRP-20 WHO should USE a QRP TRANSMITTER? Circuit DescriptionBlock Diagram Parts Supplied with QRP20 Transmitter KIT CapacitorsQRP-20 QRP20 Parts Layout Diagram LEARN-AS-YOU-BUILD Transmitter Assembly Strategy First Assembly StepsQRP-20 Building the VXO Variable Crystal Oscillator Halftime Suggestion Further Assembly Crystal Oscillator TestingBuffer and RF Amplifier Wiring Your Power Supply and RF Output Power Initial TestsVerifying Transmitter RF Output Maximizing RF Power Output TRANS-RECEIVE OperationRamsey Electronics CASE, Knob & Hardware Option Other Enclosure RecommendationsTroubleshooting Guide Final ConsiderationsQRP-20 Ramsey Kit Warranty Ramsey Model NO. QRP20 Meter CW Transmitter KIT

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.
Top Page Image Contents