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© 2012 by RF Monolithics, Inc. DN-900 Series - 07/30/12
DN-900
Series
Rating Value Units
Power Supply Input Voltage Range -0.5 to +24 V
Non-Operating Ambient Temperature Range -40 to +85 oC
DN-900 Series Absolute Maximum Ratings
DN-900 Series Specifications
Characteristic Sym Notes Minimum Typical Maximum Units
Operating Frequency Range 902.75 927.25 MHz
Hop Dwell Time 5 200 ms
Number of RF Channels in a Subband 50
Modulation FSK
RF Data Transmission Rates 38.4, 115.2, 200 and 500 kbps
Standard Antenna Internal 2 dBi directional antenna
Receiver Sensitivity through 2 dBi Antenna:
10-5 BER @ 38.4 kb/s -110 dBm
10-5 BER @ 200 kb/s -100 dBm
10-5 BER @ 500 kb/s -96 dBm
EIRP Output Power Levels through 2 dBi Antenna:
38.4 to 200 kbps 1.58, 15.8, 100, 395, 790, 1580 mW
500 kbps 1.58, 15.8, 135 mW
900 MHz
Wireless
Serial
Modems
The DN-900 series 900 MHz serial modems provide ready-to-use solutions for robust wire-
less data communications in the 900 MHz ISM band. There are currently three products in
the DN-900 series, the DN-900G, the DN-900I and the DN-900U. The DN-900G provides an
RS-232C serial interface. The DN-900I offers a two-wire, multi-drop RS-485 interface plus a
selectable RS-232C interface for configuration programming. The DN-900U provides a USB
interface. DN-900 series modems are based on RFM’s DNT900 frequency hopping spread
spectrum (FHSS) transceiver, and can communicate with other DNT900-based RFM products
as well as customer developed products. DN-900 series modems consist of a radio module in
a NEMA 4X/IP66 waterproof case connected to a serial interface adapter by a power and sig-
nal cable that allows the radio module to be located remotely at a point of good RF propaga-
tion. DN-900 series modems are well-suited for serial data networks carrying moderate traffic
that need robust communications in locations with non-ideal RF propagation and/or where RF
interference or noise are present.
- 900 MHz RS-232C, RS-485/RS-232C and USB Serial Modems
- Optional 128-Bit AES Encryption
- Point-to-point, Point-to-multipoint, Peer-to-peer and
Tree-routing Network Capabilities
- Frequency Hopping Spread Spectrum Transceiver
- Transceiver Housed in a NEMA 4X/IP66 Waterproof Case
- RF Data Rate Configurable from 38.4 to 500 kbps
- Transmitter Power up to 1.58 W EIRP using Internal Antenna
- FCC and Canadian IC Certified for Unlicensed Operation
Preliminary
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© 2012 by RF Monolithics, Inc. DN-900 Series - 07/30/12
Characteristic Sym Notes Minimum Typical Maximum Units
Optional External Antenna Connector Reverse TNC (RTNC)
External Antenna Impedance 50 ohms, VSWR < 3:1
Direct Receiver Sensitivity through RTNC Connector:
10-5 BER @ 38.4 kb/s -108 dBm
10-5 BER @ 200 kb/s -98 dBm
10-5 BER @ 500 kb/s -94 dBm
Direct Output Power Levels through RTNC Connector:
38.4 to 200 kbps 1, 10, 63, 250, 500, 1000 mW
500 kbps 1, 10, 85 mW
Network Topologies Point-to-Point, Point-to-Multipoint,
Peer-to-Peer, Tree-Routing
Access Scheme TDMA/CSMA
Number of Remote Nodes, TDMA Mode 1 16
Number of Remote Nodes, CSMA Mode Limited only by traffic density
DN-900G RS-232C Configuration 9-pin connector, hardware flow control optional
DN-900I RS-232C Configuration 3-wire, no hardware flow control
DN-900I RS-485 Configuration 2-wire, multi-drop capable
DN-900U USB Configuration USB Type B connector
Serial Port Baud Rates 1.2, 2.4, 4.8, 9.6, 19.2, 28.8,
38.4, 57.6, 76.8, 115.2, 230.4, 460.8 kbps
Signal Cable Length Options
(see Ordering Guide on Page 5) 4, 50, 100, 300 ft
DC Power Supply Voltage Range, up to 50 ft signal cable +6 +24 Vdc
DC Power Supply Voltage Range, 50 ft to 300 ft cable +12 +24 Vdc
DC Power Supply Ripple, 1.5 A load 250 mVP-P
Peak Transmit Mode DC Power 6.8 W
Average Receive Mode Power:
Base, Continuous Data Stream 760 mW
Remote, Linked, No Data 317 mW
Remote, Continuous Data Stream, 9.6 kbps 345 mW
Remote, Continuous Data Stream, 115.2 kbps 428 mW
Interface Adapter Nominal Dimensions 3.85 x 1.70 x 0.85 inches
(80x43x22mm)
Radio Module Case Rating NEMA 4X/IP66 outdoor enclosure
Radio Module Nominal Dimensions 5.15 x 5.00 x 1.40 inches
(131 x 127 x 36 mm)
Radio Module Mounting Flange with pre-drilled mounting holes; mount
flange to mast with bolts or hose clamps
Operating Temperature Range -40 85 oC
Operating Relative Humidity Range, Non-condensing 10 90 %
DN-900 Series Specifications
DN-900 Series Modem Operation
The DN-900 series 900 MHz modems provide high perfor-
mance, ready-to-use solutions for robust wireless data com-
munications in the 900 MHz ISM band. There are currently
three products in the DN-900 series, the DN-900G, the
DN-900I, and the DN-900U. The DN-900G provides an
RS-232C serial interface with optional flow control. The
DN-900I offers a two-wire, multi-drop RS-485 interface plus
a selectable three-wire RS-232C interface for configuration
programming. The DN-900U provides a USB interface.
DN-900 series modems are based on RFM’s DNT900 fre-
quency hopping spread spectrum (FHSS) transceiver, and
can communicate with other DNT900-based RFM products,
as well as customer developed products.
As shown in Figure 1, DN-900 series modems consist of a
radio module in a NEMA 4X/IP66 waterproof case with an
internal 2 dBi directional antenna, a signal cable that carries
power and data, and an interface adaptor that includes a
power supply connector and the appropriate serial data con-
nector. The radio module can optionally be provided with a
RTNC antenna connector in lieu of the internal antenna (see
Ordering Guide on Page 5). DN-900 serial modems with the
RTNC connector are compatible with RFM’s complete line of
900 MHz antennas, allowing extended operating range
where allowed by local regulations.
DN-900 series modems are supplied with a 110/220 VAC
wall-plug power supply that includes an international plug
set. Optionally, DN-900 series modems can be powered
from a user-supplied DC source as described in the specifi-
cations table. The signal cable can specified as 4, 50, 100 or
300 feet in length (see Ordering Guide on Page 5), which al-
lows the radio module to be located remotely indoors or out-
doors at a point of good RF propagation. DN-900 modems
can transmit data from 38.4 to 500 kbps, and the transmitter
output power can be set from 1.58 mW to 1.58 W EIRP
when using the internal antenna.
DN-900 series modems are well-suited for serial data net-
works carrying moderate traffic that need robust communi-
cations in locations with non-ideal RF propagation and/or
where RF interference or noise are present. DN-900 serial
modems can operate in point-to-point, point-to-multipoint,
peer-to-peer and tree routing DNT900-based wireless net-
works.
DN-900 data modems are shipped configured to transmit
transparent data, which requires no protocol formatting. All
that is required to set up a transparent point-to-point serial
data link to configure one modem as a base unit using a
simple PC-based utility. DN-900 series modems can also
operate in protocol mode, which is supported by a rich set of
configuration parameters that allow a wide range of network
layouts and configurations to be optimized.
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© 2012 by RF Monolithics, Inc. DN-900 Series - 07/30/12
Figure 1
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© 2012 by RF Monolithics, Inc. DN-900 Series - 07/30/12
Ref Name I/O Description
T +PWR I The center coaxial conductor (tip) is the positive DC power input.
R GND - The outer coaxial conductor (ring) is the DC power ground.
G PWR O Green LED indicates the unit is powered.
A LINK O Amber LED indicates the unit is linked.
DN-900G Serial Port DB9 Connector Description
Pin Name I/O Description
1 DCD O This pin is an output indicating the modem is linked to the radio network.
2 RADIO_TXD O This pin is the DN-900G serial data output.
3 RADIO_RXD I This pin is the DN-900G serial data input.
4 DTR I This pin is the data terminal ready input from the DN-900G host.
5 GND - This pin is signal ground.
6 - - No connection.
7 HOST_RTS I This pin is the request to send input from the DN-900G host.
8 HOST_CTS O This pin is the clear to send output from the DN-900G.
9 - - No connection.
Pin Name I/O Description
1 +PWR I This terminal is the positive power supply input, +6 to +24 V.
2 GND - This terminal is a power supply and signal ground.
3 485 EN I When this terminal is unconnected, serial operation is RS-232C. When this terminal is grounded
to terminal 2 or 4, serial operation is RS-485.
4 GND - This terminal is a power supply and signal ground.
5 TX/A O This terminal transmits data to the host (RS-232C TxD or RS-485 A signal).
6 RX/B I This terminal receives data from the host (RS-232C RxD or RS-485 B signal).
DN-900G/DN-900U Power Connector and LED Description
DN-900I Serial Port Terminal Block Description
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© 2012 by RF Monolithics, Inc. DN-900 Series - 07/30/12
Note: Specifications subject to change without notice.
Part # M-0900-5000, Rev A
4 . 4 0
( 1 1 2 )
5 . 0 0
( 1 2 7 )
3 . 2 0
( 8 1 )
1 . 4 0
( 3 6 )
5 . 1 5
( 1 3 1 )
4 . 8 0
( 1 2 2 )
=
D N - 9 0 0 S e r i e s T r a n s c e i v e r C a s e
D i m e n s i o n s i n
i n c h e s a n d ( m m )
Figure 2
DN-900 Serial Modem Part Number Ordering Guide
Serial Interface Antenna/Connector
Cable Length, feet
4 50 100 300
RS-232C, DB9 Connector Internal 2 dBi Antenna DN-900G-4 DN-900G DN-900G-100 DN-900G-300
RS-232C, DB9 Connector RTNC Connector DN-900GX-4 DN-900GX DN-900GX-100 DN-900GX-300
RS-485/RS-232C, 6-Pin Terminal Block Internal 2 dBi Antenna DN-900I-4 DN-900I DN-900I-100 DN-900I-300
RS-485/RS-232C, 6-Pin Terminal Block RTNC Connector DN900IX-4 DN-900IX DN-900IX-100 DN-900IX-300
USB Type B Connector Internal 2 dBi Antenna DN900U-4 DN-900U DN-900U-100 DN-900U-300
USB Type B Connector RTNC Connector DN900UX-4 DN-900UX DN-900UX-100 DN-900UX-300
