TXM-433-RM Linx Technologies Inc, TXM-433-RM Datasheet - Page 9

• Manufacturer Part Number: TXM-433-RM
• Description: TRANSMITTER RF 433MHZ
• Manufacturer: Linx Technologies Inc
• Series: RMr

Specifications of TXM-433-RM

• Frequency: 433MHz
• Applications: ISM, Remote Monitoring, Telemetry
• Modulation Or Protocol: ASK, OOK
• Data Rate - Maximum: 10 kbps
• Power - Output: -4dBm ~ 4dBm
• Current - Transmitting: 6mA
• Data Interface: PCB, Through Hole
• Antenna Connector: Through Hole
• Voltage - Supply: 5.9 V ~ 9 V
• Operating Temperature: -10°C ~ 55°C
• Package / Case: SIP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -
• Memory Size: -
• Other names: TXM-433-RM-R

COMMON ANTENNA STYLES
Whip Style
418MHz = 6.7"
433MHz = 6.5"
Loop Style
1/4 wave wire lengths fo r
R M f r e q u e n c i e s :
Helical Style
There are literally hundreds of antennas styles that can be successfully employed with
the RM Seri e s. Fo l l owing is a brief discussion of the three styles most commonly utilize d
in compact RF designs. Additional antenna info rmation can be found in Linx application
notes #00500, #00100, #00126 and #00140.
A helical antenna is precisely fo rmed from wire or rod. A helical
antenna is a good choice for low-cost products requiring ave ra g e
range perfo rmance and internal concealment. A helical can detune
badly in proximity to other objects and its bandwidth is quite narrow
so care must be exercised in layout and placement.
product's PCB. This makes it the most cost-effe c t i ve of antenna
u t i l i ze d . The element can be made self-resonant or ex t e rn a l l y
resonated with discrete components. Despite its cost adva n t a g e s,
A loop- or trace-style antenna is normally printed directly on a
s t y l e s. There are a va riety of shapes and layout styles which can be
PCB antenna styles are generally inefficient and useful only for short -
range applications. Loop-style antennas are also ve ry sensitive to
changes in layout or substrate dielectric which can introduce
consistency issues into the production process. In addition, pri n t e d
styles initially are difficult to engineer, requiring the use of ex p e n s i ve
equipment including a netwo rk analyze r. An improperly designed loop
will have a high SWR at the desired frequency which can introduce
substantial instability in the RF stages.
Linx offers a low-cost planar antenna called the “ S P L AT C H ” which is
an excellent alter n a t i ve to the sometimes problematic PCB tra c e
s t y l e. This tiny antenna mounts directly to a product's PCB and
requires no testing or tuning. Its design is stable even in compact
applications and it provides excellent perfo rmance in light of its
compact size.
from wire or rod, but most product designers opt for the improve d
p e r fo rmance and cosmetic appeal of a professionally made model.
To meet this need, Linx offers a wide va riety of straight and
c o n n e c t o ri zed mounting styles.
The wavelength of the operational frequency determines an
a partial 1/4-wave antenna is normally employe d . Its size and
n a t u ral radiation resistance make it well matched to Linx modules.
The proper length for a 1/4-wave antenna can be easily fo u n d
height of the antenna by using a helical winding. This decreases
A whip-style monopole antenna provides outstanding ove ra l l
p e r fo rmance and stability. A low-cost whip can be easily fa b ri c a t e d
redu ced-he ight w hip - sty le ant en nas in per m an en t and
antenna's ove rall length. Since a full wavelength is often quite long,
using the fo rmula below. It is also possible to reduce the ove ra l l
the antenna's bandwidth but is an excellent way to minimize the
antenna's physical size for compact applications.
W h e r e :
L=length in feet of quart e r - wave length
F = o p e rating frequency in megahert z
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