TRANSMITTER OPERATION

ACTIVE-TUNING ANTENNA SYSTEM (ATAS-100/-120)OPERATION

The optional ATAS-100/-120Active-Tuning Antenna System provides operation on a number of HF bands (7/14/21/28 MHz) plus 50 MHz, 144 MHz, and 430 MHz. The FT-857pro- vides microprocessor control of the tuning mechanism in the ATAS-100/-120for conve- nient automatic tuning.

Before operation can begin, you must instruct theFT-857’s microprocessor that the ATAS- 100/-120is being used. This is done using the Menu Mode:

1.Press and hold in the [FUNC] key for one second to activate the Menu mode.

2.Rotate the SELECT knob to recall Menu Mode No-001[EXT MENU], then rotate the DIAL to change the setting to “ON” to enable the extended Menu Mode.

3.Rotate the SELECT knob to recall Menu Mode N0-085[TUNER/ATAS]. The default setting for this Menu is “OFF.” Rotate the DIAL to change the setting to “ATAS (ALL),” if you are using the ATAS-100/-120for all bands (you must connect an external diplexer to combine the two antenna ports so as to use the ATAS-100/-120on all bands). Or make the setting “ATAS (HF&50),” if you are using the ATAS-100/-120on 7 ~ 50 MHz, with a dual-band VHF/UHF antenna connected separately to the 144/430 MHz antenna port. If you are just using the ATAS-100/-120on the HF bands only, with a dual-band VHF/UHF antenna connected separately to the 144/430 MHz antenna port (no 50 MHz operation) make the setting “ATAS (HF).”

4.Press and hold in the [FUNC] key for one second to save the new setting and exit to normal operation.

Automatic Tuning

1.Press the [FUNC] key, then rotate the SELECT knob as needed, to recall Multi Func- tion Row “k” [TUNE, DOWN, UP].

2.Press the [A](TUNE) key to turn the ATAS-100/-120on (this action only supplies volt- age to the antenna at this point; re-tuning does not begin). The “ATAS” will appear on the LCD.

3.Now press and hold in the [A](TUNE) key for one second to initiate ATAS-100/-120tuning. The transmitter will automatically be activated, a carrier will be sent, and the antenna’s length will be adjusted for best SWR.

4.If the microprocessor determines that the antenna’s length is radically incorrect from the optimum value, no carrier will be sent out. Instead, in the receive mode, the antenna will retract to its longest or shortest position (this may take up to one minute). While this is happening, do not press the [A](TUNE) key again.

When the ATAS-100/-120reaches its minimum length, automatic tuning will be initi- ated, and the transmitter will automatically shut off when a satisfactory SWR is achieved.

5.On the 144 MHz and 430 MHz bands, the ATAS-100/-120does not require a tuning process. SWR will be satisfactory when the antenna is fully retracted.

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FT-857 Operating Manual

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Vertex Standard FT-857 manual Automatic Tuning, ACTIVE-TUNING Antenna System ATAS-100/-120OPERATION
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FT-857 specifications

The Vertex Standard FT-857 is a compact and versatile all-mode transceiver that has become popular among amateur radio operators since its introduction. With its ability to operate in VHF, UHF, and HF bands, the FT-857 caters to a diverse range of communication preferences and provides exceptional performance for both mobile and base station applications.

One of the key features of the FT-857 is its coverage of a broad frequency range, spanning from 160 meters to 2 meters and covering the 70 cm band. This wide frequency coverage allows amateur operators to communicate with fellow enthusiasts across various bands, ensuring versatility in operational environments. The FT-857 offers an output power of up to 100 watts on HF and 50 watts on VHF/UHF, providing sufficient power for effective communication, whether in local or distant contacts.

Another distinctive characteristic of the FT-857 is its all-mode capability. It supports various modes of operation, including SSB, CW, AM, and FM, making it suitable for different operating styles and preferences. The inclusion of advanced digital signal processing (DSP) technology enhances audio clarity and offers noise reduction features, which are crucial in crowded bands. This DSP capability also aids in improving signal quality and overall communication experience.

Portability is a significant advantage of the FT-857. Its compact size and lightweight design make it an excellent choice for field operations and portable setups. Additionally, the transceiver is well-equipped with features such as built-in memory channels, allowing users to save and quickly access frequently used frequencies. The FT-857 also includes a built-in automatic antenna tuner, which makes it easier for operators to set up and optimize their antenna configurations without requiring additional external devices.

The FT-857 is designed with user-friendly controls and a clear LCD display, enabling operators to quickly adjust settings and monitor communication details without confusion. The visibility of the display is especially vital for use in different lighting conditions, ensuring that users can operate efficiently whether in bright sunlight or low light conditions.

In summary, the Vertex Standard FT-857 is a highly capable, compact transceiver that offers an effective solution for amateur radio communication. With its all-band, all-mode capabilities, robust DSP technology, and user-friendly design, the FT-857 remains a popular choice for both enthusiasts and professionals alike, facilitating engaging communication experiences across multiple bands and modes.
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