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ANTENNA CONSIDERATIONS

The SC-PA transceivers feature a unique RP-SMA

antenna connector. This connector is designed to

allow the convenience and flexibility of a detachable

antenna while maintaining compliance with FCC

guidelines.

Linx and other manufacturers sell a variety of

antenna styles and connectors designed to mate

with the module’s RP-SMA connection. It is

important to note, however, that the module must

be used with the appropriate Linx antennas in order

to retain its pre-approved status. Other antennas

may be used; however, recertification would be

necessary prior to offering the product for sale.

The antennas pictured below illustrate styles that

would be commonly employed. Please contact Linx

or visit www.linxtechnologies.com for the most

current information on compliant antenna styles.

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Clamps into

molded case

Clamps into

molded case

Flange hides

hole

Serves as

rear flange

Plastic/Metal

Case

Use of nut

optional

Figure 9: Compatible Linx Antenna Styles

Figure 10: Mounting Options

CW

RH

RCS

RCL

The following general rules should help in maximizing antenna performance:

1.

Proximity to objects such as a user’s hand or body, or metal objects will

cause an antenna to detune. For this reason the antenna shaft and tip

should be positioned as far away from such objects as possible.

2.

Keep the antenna away from other metal components, particularly large

items like transformers, batteries, and PCB tracks and ground-planes. The

space around the antenna can be as important as the antenna itself.

3.

The ground-plane acts as a counterpoise, forming, in essence, a 1/2-wave

dipole. For this reason adequate ground-plane area is essential. As a

general rule the ground-plane to be used as counterpoise should have a

surface area

≥ the overall length of the 1/4-wave radiating element.

4.

Remove the antenna as far as possible from potential interference sources.

Any frequency of sufficient amplitude to enter the receiver’s front end will

reduce system range, cause increased bit errors, and can even prevent

reception entirely. There are many possible sources of internally generated

interference. Switching power supplies, oscillators, even relays can also be

significant sources of potential interference.