with R3 to the junction with the battery positive point. Because the resistance of the photocell changes according to how much light is present, this will cause the audio tone to change as well. In the same way you can try placing a thermistor either across R4 or in place of it (depending on the value of the thermistor). Thermistors are devices whose resistance changes depending on temperature. Be creative! Experiment! That’s what Ramsey kits are all about.

CHANGING YOUR CRYSTAL

It is possible to change the frequency of your MR6 kit in two ways. The first is to change the value of C12. Increasing or decreasing the value of C12 will cause the circuit to oscillate at a slightly different frequency. Remember that you’ll still be in the 2 meter band, since that’s what the kit was designed for. The other way to change the frequency is to change the crystal. The sche- matic shows the different multiplication factors for different common crystals. If you need to order a crystal, one of the places you can call is Jan Crystal at 800-JAN-XTAL. The specifications you need are as follows: parallel resonant, 32pF load capacitance, HC-18/U holder, wire leads.

CONCLUSION

We sincerely hope that you have enjoyed the construction and use of this Ramsey Kit. As always, we have tried to compose our manual in the easiest, most “user friendly” format that is possible. As our customers, we value your opinions, comments, and additions that you would like to see in future publications. Please submit comments or ideas to:

Ramsey Electronics Inc.

590 Fishers Station Drive Victor, NY 14564

And once again, thanks from the folks at Ramsey!

MR6 • 14

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Ramsey Electronics MR6 manual Changing Your Crystal, Conclusion
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MR6 specifications

The Ramsey Electronics MR6 is a sophisticated communication device tailored for amateur radio enthusiasts, providing a blend of innovative technology and user-friendly operation. This versatile receiver primarily operates within the 2-meter FM band, allowing users to access a wide array of frequencies while ensuring clarity and efficient signal processing.

One of the hallmark features of the MR6 is its exceptional sensitivity, which enhances reception quality for both local and distant transmissions. The receiver employs advanced filtering technologies that minimize interference from adjacent channels, ensuring that users receive crisp, clear audio. Additionally, the low noise figure of the MR6 contributes to its ability to pick up even faint signals, making it an invaluable tool for radio communication.

The front panel of the MR6 is designed with user accessibility in mind, featuring clearly labeled knobs and buttons for quick adjustments. The large frequency display allows operators to monitor their current channel effortlessly, while the ergonomic layout ensures that essential controls are readily accessible during operation. This user-centric design makes the device suitable for both seasoned operators and newcomers to the world of amateur radio.

Another notable characteristic of the MR6 is its built-in repeater capability. This feature allows users to access repeaters in their area, extending communication range significantly. Repeater functionality is essential for hobbyists looking to connect with other operators over greater distances, facilitating collaboration and community engagement.

The MR6 also supports a variety of modulation modes, including FM and narrowband FM, which are important for adapting to different communication needs. This flexibility further enhances its usability in various environments, whether for casual chatting or emergency communications.

Power efficiency is another strong point of the MR6, as it offers low power consumption without sacrificing performance. This attribute is particularly valuable for field operations, where battery life can be a concern. Users can operate the device for extended periods, making it ideal for outdoor adventures or emergency preparedness scenarios.

In summary, the Ramsey Electronics MR6 is a well-engineered, feature-rich communication device designed for amateur radio use. Its sensitivity, user-friendly interface, repeater functionality, and power efficiency make it a top choice for both casual and dedicated radio operators looking to enhance their communication capabilities. Whether for hobbyist exploration or critical communications, the MR6 stands out as a reliable and effective solution.
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