Ramsey Electronics CT255 manual

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ˆ16. Install C2, 10 uF electrolytic capacitor. Remember to observe polarity with electrolytic capacitors! Check the parts placement diagram for correct orientation.

ˆ17. Install R34, 10K ohm (brown-black-orange).

ˆ18. Install R30, 10K ohm (brown-black-orange).

ˆ19. Install R4, 10K ohm (brown-black-orange).

ˆ20. Install R2, 10K ohm (brown-black-orange).

ˆ21. Install C1, 1 uF electrolytic capacitor. Remember to observe correct polarity!

ˆ22. Install R1, 47K ohm (yellow-violet-orange).

ˆ23. Install R15, 100K ohm (brown-black-yellow).

ˆ24. Install C6, .1 µF disc capacitor (marked 104 or .1). Disc capacitors are not polarized, so either direction is fine.

ˆ25. Install R39, 1K ohm (brown-black-red).

ˆ26. Install R37, a precision 1K ohm (brown-black-black-brown-brown).

ˆ27. Install headers H2 and H1 by slipping the protruding pins on the short side through the circuit board and soldering. Solder all three pins.

ˆ28. Install C3, .1 µF disc capacitor (marked 104 or .1).

ˆ29. Install R31, a precision 4.22K ohm (yellow-red-red-brown-brown).

ˆ30. Install R27, a precision 1.43K ohm (brown-yellow-orange-brown- brown).

ˆ31. Install R40, the last 10K ohm (brown-black orange).

ˆ32. Install R23, a precision 1.82K ohm (brown-gray-red-brown-brown- brown).

ˆ33. Install R22, a precision 10K ohm (brown-black-black-red).

ˆ34. Install C5, .1 µF disc capacitor (marked 104 or .1).

Whew! That was some work. But we’re almost done and some decisions need to be made before continuing. It’s a good time now to re-check all your work up to this point. Carefully inspect the circuit board for stray leads or open solder connections, trim and touch up any that need work.

Next, while we are at our best, we will install the LED segments for the display. (L)ight (E)mitting (D)iodes are just that, a diode junction that emits light of a particular wavelength when forward biased, so pay attention to the polarity of the diodes as shown in the parts placement diagram. Remember that this will be the most observed part of the entire kit, so take your time and

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Contents Computemp 255 Binary Thermometer KIT Ramsey Transmitter Kits KIT Assembly CB B OA RD in CA SE IntroductionCircuit Description Binary counterScaling to Celsius DAC Digital to Analog ConverterADC Analog to Digital Converter? In a sense… More on the ADC Oh that extra countFor the complicated Fahrenheit design How the counter oscillator worksRestarting the conversion cycle CT255 Binary math Bit # Value 128 Some random parts, and what they do CT255 Schematic Diagram CT255 Parts Layout Diagram Parts Supplied with Your CT255 KIT CapacitorsResistors SemiconductorsRamsey LEARN-AS-YOU-BUILD KIT Assembly Enough of that ... let’s get startedCT255 Thermometer Assembly Instructions CT255 CT255 CT255 Front View LM35DZ Assembly Instructions for Custom Case CongratulationsUSE of Your Computemp Troubleshooting Guide Still Having TROUBLE?Conclusion Ramsey Kit Warranty Required Tools Additional Suggested ItemsRamsey ELECTRONICS, INC Fishers Station Drive Victor, New York Phone 585

CT255 specifications

The Ramsey Electronics CT255 is a versatile and advanced communication tool designed for radio enthusiasts and professionals alike. As a 2-meter FM transceiver, it is known for its robust performance and extensive feature set, making it ideal for both casual users and serious operators.

One of the standout features of the CT255 is its compact design, allowing for easy integration into various environments such as home stations or portable setups. The unit is built with user-friendliness in mind, featuring an intuitive interface with a clear display and easily accessible controls. This ensures that users can quickly tune into their desired frequencies and modify settings without extensive technical knowledge.

The CT255 operates on a frequency range from 144 to 148 MHz, providing access to the popular 2-meter amateur radio band. This frequency capability is complemented by an impressive output power of up to 25 watts, ensuring robust communication over extended distances. It also includes a built-in automatic repeater shift, which simplifies contacts through repeaters, making it an excellent choice for those looking to enhance their communication range.

In terms of technology, the CT255 employs advanced digital signal processing (DSP), which significantly improves audio clarity and reduces background noise. This makes communication clearer, even in less-than-ideal conditions. Additionally, the transceiver features an array of scanning functions, including memory scan and priority scan, allowing users to monitor multiple channels effortlessly.

The CT255 comes equipped with multiple memory channels, enabling easy access to frequently used frequencies. This feature is particularly useful for users who participate in various nets or have multiple repeaters they commonly contact. Moreover, the unit supports CTCSS and DCS tones, which adds an extra layer of privacy and reduces interference from unwanted transmissions.

Safety and durability are also key characteristics of the CT255. The robust construction ensures it can withstand the rigors of regular use, making it suitable for field operations. It is designed with heat dissipation features to prevent overheating during prolonged use, ensuring reliability during critical communications.

In conclusion, the Ramsey Electronics CT255 is a well-rounded transceiver that brings together advanced technology, user-centric design, and excellent performance. Its range of features makes it an appealing choice for radio amateurs seeking a dependable and efficient communication solution. Whether for casual chatting or emergency communications, the CT255 stands out as a reliable tool that meets the demands of modern radio users.
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