INSTALLATION

ANTENNA CONSIDERATIONS

rest of the vehicle’s body, using a heavy braid bonded securely at both ends, to ensure that as much counterpoise as possible is secured. In portable operation, be sure to lay out radials (or otherwise construct a n image plane for the vertical monopole); it is not adequate simply to connect a vertical radiating element to the rear panel Antenna jack of this transceiver, with- out providing a suitable counterpoise.

Base Station Antenna Installations

When installing a “balanced” antenna such as a Yagi or dipole, remember that the FT-857is designed for use with an (unbalanced) coaxial feedline. Always use a balun or other balanc- ing device so as to ensure proper antenna system performance.

Use high-quality 50 W coaxial cable for the lead-in to your FT-857transceiver. All efforts at providing an efficient antenna system will be wasted if poor quality, lossy coaxial cable is used. Losses in coaxial lines increase as the frequency increases, so a coaxial line with 0.5 dB of loss at 7 MHz may have 6 dB of loss at 432 MHz (thereby consuming 75% of your transceiver’s power output!). As a general rule, smaller-diameter coaxial cables tend to have higher losses than larger-diameter cables, although the precise differences depend on the cable construction, materials, and the quality of the connectors used with the cable. See the cable manufacturer’s specifications for details.

For reference, the chart below shows approximate loss figures for typically- available co- axial cables frequently used in HF installations.

Loss in dB per 30 m (100 feet) for Selected 50-ohm Coaxial Cables

CABLE TYPE

 

LOSS

 

1.8 MHZ

28 MHZ

432 MHZ

 

RG-58A

0.55

2.60

>10

RG-58 Foam

0.54

2.00

8.0

RG-8X

0.39

1.85

7.0

RG-8A, RG-213

0.27

1.25

5.9

RG-8 Foam

0.22

0.88

3.7

Belden 9913

0.18

0.69

2.9

7/8” “Hardline”

< 0.1

0.25

1.3

Loss figures are approximate; consult cable manufacturer’s cata- logs for complete specifications.

Always locate antennas such that they can never come in contact with outdoor power lines in the event of a catastrophic support or power-pole structural failure. Ground your antennas’ support structure(s) adequately, so as to dissipate energy absorbed during a lightning strike. Install appropriate lightning arrestors in the antenna coaxial cables (and rotator cables, if rotary antennas are used).

In the event of an approaching electrical storm, disconnect all antenna lead-in, rotator cables, and power cables completely from your station if the storm is not immediately in your area.

FT-857 Operating Manual

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Vertex Standard FT-857 manual Base Station Antenna Installations
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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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