TXM-900-HP-II Linx Technologies Inc, TXM-900-HP-II Datasheet - Page 13

• Manufacturer Part Number: TXM-900-HP-II
• Description: TRANSMITTER RF 900MHZ 8-CHANNEL
• Manufacturer: Linx Technologies Inc
• Series: HP2r

Specifications of TXM-900-HP-II

• Frequency: 902MHz ~ 928MHz
• Applications: ISM, RKE, Security and Fire Alarms
• Modulation Or Protocol: FM, FSK
• Data Rate - Maximum: 50 kbps
• Power - Output: -3dBm ~ 4dBm
• Data Interface: PCB, Through Hole
• Antenna Connector: Through Hole
• Voltage - Supply: 2.17 V ~ 16 V
• Operating Temperature: 0°C ~ 70°C
• Package / Case: SIP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -
• Memory Size: -
• Current - Transmitting: -
• Other names: TXM-900-HP2; TXM-900-HP2

Whip Style
1/4 wave wire lengths
902-928MHz =3.06”
Loop Style
COMMON ANTENNA STYLES
HP Antenna Selection Chart
for HP-II frequencies:
Helical Style
PARAMETER
Ultimate performance
Ease of design setup
Size
Immunity to proximity effects
HP Range (
and variations that can be employed. Following is a brief discussion of the three
styles most commonly utilized in compact RF designs. The selection chart
broadly categorizes key areas of antenna performance. In reviewing this section
it is important to recognize that each antenna style will produce widely varying
antenna information can be found in Linx application notes #00500, #00100,
#00126 and #00140.
From a coat hanger to a tuned Yagi, there are literally hundreds of antenna styles
results based on the specific design execution and optimization. Additional
open ground to similar antenna
=FAIR
A whip-style antenna provides exceptional performance and is easy to
integrate. A low-cost whip is generally made of a wire or rod while more
expensive whip designs are encapsulated in rubber or plastic to
antenna element. A whip is often combined with a helical winding to
“base loading”. The wavelength of the frequency to be received or
is generally used. For testing, or even production, a whip can be easily
made from a piece of solid conductor wire cut to the appropriate
length.Length for a half-wave is easily determined using the following
detuning (i.e., a user’s body) and is easily concealed inside products
applications requiring maximum range-performance.
improve appearance and minimize the potential for damage to the
reduce the overall length. This technique is commonly referred to as
transmitted determines an antenna’s length.Since a full-wave antenna
is quite long, a partial wavelength antenna such as a 1/2- or 1/4-wave
formula.The resultant length may be divided in half for a quarter-wave.
making it the most cost-effective of antenna styles. There are many
different styles and shapes of loops which can be utilized, including
spirals and rectangles. A loop has excellent immunity to proximity
which have a plastic case. Despite these advantages, a loop is difficult
to match and tune without expensive RF test equipment.An improperly
designed loop will have a very high SWR and may induce harmonics.
For this reason a helical or whip style is usually a better choice for
antenna is very efficient given its small size. The helical is an excellent
choice for products requiring good ra n g e - p e r fo rmance and a
concealed internal antenna element. Care must be exercised in
placement, however, as a helical detunes badly when located in
proximity with other conductive objects. Because a helical has a high
“Q” factor its bandwidth is very narrow and inter-coil spacing has a
pronounced effect on antenna performance. For this reason, it is
usually best to utilize a premade helical which has been professionally
optimized to achieve maximum performance.
A loop or track-style antenna is usually printed directly on the PCB,
A helical is a wire coil usually wound from steel, copper or brass. This
=GOOD
)
Where:
L=length in feet of half-wave length
F=operating frequency in megahertz
LOOP
400 ft.
=EXCELLENT
HELICAL
600 ft.
1,000+ ft.
WHIP
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