‰46. Install C14, .01 uf (marked .01 or 103 or 10 nf).

‰47. Install C9, .01 uf (marked .01 or 103 or 10 nf).

‰48. Install D1, 1N4002 (large black epoxy body), notice placement of banded end.

‰49. Install L4, 100 uh inductor [brown-black-brown-silver].

‰50. Install R8, 47K (yellow-violet-orange).

‰51. Install C7, .01 uf (marked .01 or 103 or 10 nf).

‰52. Install C12, 68 pf (marked 68 or 68K).

‰53. Install Q3, 2N3053. Again observe the placement of the tab.

‰54. Install the slip-on metal heatsink on Q3. Insure that it does not contact adjacent components.

The assembly of your QRP transmitter is now completed. If you somehow skipped or improvised on our "halftime" instructions, NOW is the time to make proper preparations for testing and using your transmitter.

As we suggest in all Ramsey Electronics kit projects, now might also be an excellent time to take a break and then come back to re-check your connections, or have a friend go over them. Give extra attention to the work associated with Q2 and Q3. It's always easier to catch an error now, before final testing. Easier on the cicuit parts, and. . . your ego!

INITIAL TESTS:

Connect the following to the transmitter:

•Key, or keyer such as the Ramsey CW-7 CMOS keyer kit.

•12-15 VDC power source capable of 500 ma output.

•Resonant antenna with in-line QRP wattmeter, or 50-ohm 2-watt dummy load.

For initial testing, your receiver may be connected through J2 of the transmitter or to a separate receiving antenna.

•Study the following sections regarding the DC power supply and RF power indication, and test your transmitter in accord with good amateur radio practice.

YOUR POWER SUPPLY AND RF OUTPUT POWER :

For optimum performance, one or two volts of extra DC supply power can make quite a difference for this transmitter. For example, two lantern batteries in series, or 8 "D cells" obviously provide "about 12 volts" with sufficient current capability for casual operating. For maximum RF output power, use a supply of

QRP-20 • 17

Page 16 Page 18
Page 17
Image 17
Ramsey Electronics QRP20 manual Initial Tests, Your Power Supply and RF Output Power
Page 16 Page 18

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