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Radiometrix Ltd
LMT2/LMR2 Data Sheet
page 10
The antenna choice and position directly controls the system range. Keep it clear of other metal in the
system, particularly the 'hot' end. The best position by far, is sticking out the top of the product. This is
often not desirable for practical/ergonomic reasons thus a compromise may need to be reached. If an
internal antenna must be used, try to keep it away from other metal components, particularly large
ones like transformers, batteries and PCB tracks/earth plane. The space around the antenna is as
important as the antenna itself.
A. Helical antenna
B. Loop antenna
RF
C1
C2
C4
C3
RF-GND
C. Whip antenna
16.4cm
RF
0.5 mm enameled copper wire
close wound on 3.2 mm diameter former
433 MHz = 24 turns
Feed point 15% to 25% of total loop length
track width = 1mm
4 to 10 cm inside area
wire, rod, PCB-track or a combination
of these three
433 MHz = 16.4 cm total from RF pin.
2
RF
Ordering Information:
Ordering Information:
Ordering Information:
Ordering Information:
Part No.
Part No.
Part No.
Part No.
Descript
Descript
Descript
Description
ion
ion
ion
Frequency band
Frequency band
Frequency band
Frequency band
(MHz)
(MHz)
(MHz)
(MHz)
RF power
RF power
RF power
RF power
(mW)
(mW)
(mW)
(mW)
Channel spacing
Channel spacing
Channel spacing
Channel spacing
(kHz)
(kHz)
(kHz)
(kHz)
Data rate
Data rate
Data rate
Data rate
kbps
kbps
kbps
kbps
LMT2-433-5
Transmitter
433.875-434.650
10
25
5
LMR2-433-5
Receiver
433.875-434.650
25
5
LMT2-458-5
Transmitter
458.525 - 459.1
100
25
5
LMR2-458-5
Receiver
458.525 - 459.1
25
5
LMT2-433-5-12k5
Transmitter
433.875-434.650
10
12.5
5
LMR2-433-5-12k5
Receiver
433.875-434.650
12.5
5
LMT2-458-5-12k5
Transmitter
458.525 - 459.1
100
12.5
5
LMR2-458-5-12k5
Receiver
458.525 - 459.1
12.5
5
LMT2-433-10
Transmitter
433.875-434.650
10
25
10
LMR2-433-10
Receiver
433.875-434.650
25
10
LMT2-458-10
Transmitter
458.525 - 459.1
100
25
10
LMR2-458-10
Receiver
458.525 - 459.1
25
10
Note: Also available on the other UHF band frequencies subject to SAW filter availability. e.g. 315, 419, 429, 448,
465MHz etc.
Figure 7: Antenna types