Amateur Radio

Description: This device features crystal-controlled transmitters and tunable superregenerative receivers equipped with RF preamplifiers, designed for operation on the 2, 6, or 10 meter amateur bands. The highly sensitive receivers can detect signals as low as 1 microvolt, providing complete quieting at reasonable signal levels. The transmitters, with an input power of up to 5 watts, are suitable for "local" net operations, and the communication range of all models is extensive under "skip" conditions. Additional features include a built-in RF trap on the 10 meter version to minimize television interference (TVI), frequency multipliers on the 6 and 2 meter versions to enable straight-through finals from an oscillator using a fundamental crystal in the 8 MHz range, a built-in final amplifier metering jack, and a "press-to-talk" transmit/receive switch on the front panel with a "transmit-hold" position. The kit includes a ceramic element microphone and two power cords: one for the built-in AC power supply and another for use with a vibrator power supply, such as the Heathkit GP-11, for 6 or 12 volt mobile operation. Transitioning from a fixed station to mobile operation can be accomplished in minutes. The unit is aesthetically designed in a two-tone mocha and beige finish. It is versatile enough for standby, camping, emergency operation, or as a primary rig. Band changing and tune-up are easily performed with pushbutton band selection and single-control tuning. The lightweight and compact transceiver features pushbutton crystal transmit provisions for novice or QRP roundtables. Main tuning is achieved through a 6-to-1 vernier that is virtually backlash-free. A relative power meter, built-in sidetone, and portable size enhance the operating experience. The HW-8 Handbook, First Edition (1994), by Michael Bryce, suggests replacing the MPF-105 front-end in the HW-8 with a 2N4416 for improved sensitivity. He notes that the additional pin of the 2N4416 can ground the case, which can be achieved by drilling a small hole into the PCB near the new unit, or the ground can be left floating with negligible performance loss. The 2N4416 is priced at $2.50 each from RF Parts, while the 2N4416A is available from Mouser for $2.00 each, with RF Parts imposing a $25 minimum order and Mouser having no minimum order requirement. The DX-60 Amateur Transmitter, with its numerous design features, offers superior quality, performance, and reliability compared to other units in its price and power category. It is designed with high-quality components, robust construction, and an efficient circuit layout, making it an ideal choice for novice operators. Construction is straightforward, aided by comprehensive instructions, and all parts are easily identifiable. A pre-cut, cabled wiring harness simplifies the assembly process. The completed unit features a neat, functional panel layout for optimal ease of operation. From a circuit perspective, the DX-60 incorporates a built-in low-pass filter for harmonic suppression, a neutralized final for enhanced stability, grid block keying for excellent keying characteristics, and easy access to crystal sockets located on the rear chassis apron. A front panel switch allows selection of any of four crystal positions or an external VFO. The controlled-carrier modulator and silicon diode power supply are integrated into the design. Single-knob band switching covers 80 through 10 meters, while pi network output coupling ensures operational convenience. A high-quality panel meter indicates final grid or plate current to assist in tuning.

The circuit design of the described transceiver and transmitter systems emphasizes the importance of signal integrity and operational versatility. The use of crystal-controlled oscillators ensures stable frequency performance, while the superregenerative receivers enhance sensitivity, making them capable of picking up weak signals. The integrated RF trap in the 10-meter version is particularly beneficial for reducing interference from television signals, a common issue in amateur radio operations. The inclusion of frequency multipliers in the 6 and 2-meter models showcases the design's adaptability for different frequency bands, allowing for efficient signal transmission.

For mobile operations, the versatility of the power supply options enables seamless transitions between fixed and mobile setups, catering to the needs of amateur operators who require portability. The ergonomic design features, such as the pushbutton controls and the 6-to-1 vernier tuning, enhance user experience, making the devices accessible to both novice and experienced operators. The recommendation for component upgrades, such as the substitution of the MPF-105 with the 2N4416, reflects an emphasis on optimizing performance, which is crucial for achieving the best possible communication range and clarity.

Overall, the robust construction and thoughtful design of the DX-60 transmitter and the associated transceiver ensure that they meet the demands of amateur radio enthusiasts, providing reliable performance across various operational scenarios. The combination of ease of assembly, operational convenience, and high-quality components positions these devices as valuable assets for both novice and seasoned operators in the amateur radio community.All feature crystal-controlled transmitters and tunable superregenerative receivers with RF preamplifiers designed for operation on the 2, 6 or 10 meter amateur bands. The highly sensitive receivers pull in signals as low as 1 microvolt and produce complete quieting on reasonable signal levels.

The transmitters with up to 5-watt input are more than adequate for "local" net operations and the communication range of all models is unlimited under "skip" conditions. Other features include: a built-in RF trap on the 10 meter version to minimize TVI; frequency multipliers on the 6 & 2 meter versions to provide straight-through finals from an oscillator using a fundamental crystal in the 8 mc range; built-in final amplifier metering jack, and "press-to-talk" transmit/receive switch on the front panel with "transmit-hold" position.

Kit includes a ceramic element microphone and two power cords, one for use with the built-in AC power supply and one for use with a vibrator power supply such as the Heathkit GP-11 for 6 or 12 volt mobile operation. Transfer from fixed station to mobile operation in a matter of minutes. Handsomely styled in two-tone mocha and beige. Less crystal. Whether you use it for standby, camping, emergency operation, or your primary rig, the Transceiver will prove its worth.

Band changing and tune-up are easily accomplished with pushbutton band selection and single-control Tuning. The light-weight and compact Transceiver has pushbutton crystal transmit provisions for the novice or QRP roundtables.

Main tuning is accomplished through a 6-to-1 vernier that is virtually backlash free. A Relative Powermeter, built-in sidetone, and carry-along size make the Transceiver a pleasure to operate. In HW-8 Handbook, First Edition (1994), Michael Bryce recommends replacing the MPF-105 front-end in the HW-8 with a 2N4416 for a significant increase in sensitivity.

He notes, "The extra pin of the 2N4416 grounds the case, and it may be done with a small hole drilled into the PC board nearby the new unit, or the ground simple (sic) may be left `floating` with no noticeable loss in performance. " (This suggestion was not included in the Second Edition of the book. ) The 2N4416 is available for $2. 50 each at RF Parts. The 2N4416A is available at Mouser for $2. 00 each. (Note: RF Parts has a $25 minimum order; Mouser has no minimum order. ) DX-60: The DX-60 Amateur Transmitter with its many design features offers more in quality, performance, and dependability than any other unit in its price and power class!

Superbly designed throughout, the DX-60 with its high quality components, clean, rugged construction and thoughtful circuit layout makes it an ideal "first" transmitter for the novice. Construction proceeds smoothly from start to finish with the complete, informative instructions furnished.

All parts are easily identified and a precut, cabled wiring harness eliminates much of the tedious wiring. The completed unit with its neat, functional panel layout provides for maximum ease of operation. Circuit-wise, the DX-60 features a built-in low pass filter for harmonic suppression, neutralized final for high stability, grid block keying for excellent keying characteristics and easy access to crystal sockets on the rear chassis apron.

A front panel switch selects any of four crystal positions or an external VFO. Controlled-carrier modulator and silicon diode power supply are built in. Single knob bandswitching for 80 through 10 meters and pi network output coupling provide complete operating convenience. A high-quality panel meter shows final grid or plate current to aid in tuning. In every