Maxon SD-270 Series User manual

SD-270 Series Data Radio

User Manual

January 2017

FCC RF Exposure Compliance Requirements

The Federal Communications Commission (FCC), with its action in General Docket

93-62, November 7, 1997, has adopted a safety standard for human exposure to

Radio Frequency (RF) electromagnetic energy emitted by FCC regulated equipment.

Friendcom subscribes to the same safety standard for the use of its products. Proper

operation of this radio will result in user exposure far below the Occupational Safety

and Health (OSHA) and Federal Communications Commission limits.

About your SD-270 Series Data Radio

The SD-270 Series is a PLL synthesized 5-watt FM transceiver module, which is

designed for data transmission and voice communication. It can support

pre-emphasis, squelch CTCSS/DCS and audio amplifier. Two-point modulation

technology provides a good low frequency response and POCSAG protocol is

optional. The radio has a fast start-up time, low power consumption, and the

optional modem boards from 1200-19200 bps add extra applications for its use. The

die cast aluminum cabinet and lid provides resistance to RF interference with the

most requested mechanical footprint in the industry.

Should you have questions regarding the operation of the radio, please consult us at:

Maxon America, Inc. Phone: 913-859-9515

11535 W. 83rd Terrace Email: maxon@maxonamerica.com

L e n e x a , KS 66214 Website: www.maxonamerica.com

Features

C E , F C C , MRC & AS/NZS 4295: 2015 certified

Programmable 16 channels (Dip Switch Select)

External Software Channel Steering

Configurable Power Save Feature

FSK, 4FSK& GMSK Modem Options; Supports 19200 bps

Frequency Step 6.25KHz

CTCSS/DCS Encode/Decode

Fast start-up time: 5ms

SQ Programmable via PC (6 Levels)

POCSAG Modulation (Optional)

PC Programmable & Software Tune & Calibration

Applications

Industrial telemetry & wireless remote control or Paging system

Gas and oil flow monitoring

Electricity, water and gas utilities

Earthquake, weather, environmental protection

Vehicle tracking and asset tracking systems

Water monitoring, waste water management and irrigation control

Railway, police, army automation system

Aerial defense and fire alarm system

Urban lighting control

Specifications

GENERAL

Working Frequency

V: 136-174 MHz

U0: 400-440 MHz

U1: 430-470 MHz

U2: 450-490 MHz

Channel Spacing

12.5KHz/25KHz Programmable

Modulation Type

F3D/F3E

Number of Channels

Nominal Working Voltage

12V DC

Extreme Working Voltage

9.6 V～16V DC

Storage Temperature

-40℃～+80℃

Operating Temperature

-30℃～+65℃

Current

Consumption

Standby

＜100mA (65 mA @ 12V)

Transmit 5 watts RF Power

＜1.5A

Transmit 1 watt RF Power

＜1A

TX to RX Attack Time

＜5ms

RX to TX attack time

＜5ms

Frequency Error

＜2.5ppm

Antenna Connector

BNC 50Ω

External interface

DB15 Female

TRANSMITTER Specification

R F P o w e r

1W/2W/3W/4W/5W Programmable

Frequency

Deviation

25KHz Channel Spacing

＜5KHz

12.5KHz Channel Spacing

＜2.5KHz

Subsonic

0.5KHz

Audio Response

25KHz Channel Spacing

300Hz～3KHz+1/-3dB

12.5KHz Channel Spacing

300Hz～2.55KHz +1/-3dB

Adjacent

Channel Power

25KHz Channel Spacing

＜-70dBc

12.5KHz Channel Spacing

＜-65dBc

Conducted Spurious Emission

＜1GHz,＜-36dBm

＞1GHz,＜-30dBm

Modulation

Sensitivity

V o i c e

8~15mV

Data

80~130mV

TX SNR

25KHz Channel Spacing

＞45dB

12.5KHz Channel Spacing

＞40dB

RECEIVER Specification

RX Sensitivity

(12dB SINAD)

25KHz Channel Spacing

＜-119dBm Extreme＜-115dBm

12.5KHz Channel Spacing

＜-119dBm Extreme＜-115dBm

Adjacent Channel

Selectivity

25KHz Channel Spacing

＞70dB

12.5KHz Channel Spacing

＞60dB

Image Rejection

＞70dB

IF Rejection

＞70dB

Spurious Rejection

＞70dB

Intermodulation Suppression

＞65dB

Conducted Spurious Emission

＜-57dBm

Receiving Audio Distortion

＜5%

RX SNR

25KHz Channel Spacing

＞45dB

12.5KHz Channel Spacing

＞40dB

Audio Output Power

0.5W @ 8Ωload

Exterior View

Description of radio components

①DB15 Female connector

②BNC Antenna connector

③LED (Red for TX, Green for RX)

SD-270 External DB15 female Pin Assignment

SD-270 Series is manufactured by default with modem,iftheradio doesnot havea

built-in modem; the corresponding pin is defined as empty.

No.

Function

Description

Note

①

AUDIO_IN

（MOD IN）

Audio input, 3Khz LPF, Modulation

sensitivity is 100mV.

AUDIO_IN is effective only

when Pin7 (MIC)isvacantor

with +5V high level. 3KHz

LPF filter existed in audio

channel.

②

AUDIO_OUT

（AF OUT）

A u d i o o u t p u t , 3 K h z L P F . O u t p u t l e v e l a t

60% frequency deviation is 250±50mV.

This line has an internal pull-up resistor

t o + 5 V .

③

PTT

T X c o n t r o l , a c t i v e l o w , o n l y w h e n P T T i s

active AUDIO_IN and MIC IN are

effective. This line has an internal pull-

u p t o 5 V .

④

B+

(9.6～16V DC)

Positive pole input from DC p o w e r ,

nominal +12V.

⑤

P R O G

( D A T A O U T )

Programming data output, 5V TTL

⑥

BUSY

Logical level output to indicate

whether there is a carrier or not. Low

lever means carrier, high level means

nocarrier.Thislinehasapull-up to

+ 5 V .

⑦

MIC IN/RSSI

MIC IN: Microphone input.

RSSI:Todetecttheairsignalstrength.

Jumper selectable.

Can directly connect to

e l e c t r e t s M I C , t h e D C v o l t a g e

of this pin should lower than

3.5V, then MIC transmission

can be activated.

⑧

P R O G

( D A T A I N )

Programming data input, 5V TTL

⑨

SPK/POCSAG

SPK: Audio output from the audio

amplifier, @ 8Ω.

POCSAG: To transmit POCSAG code.

Jumper selectable.

AUDIO_IN is effective only

when PIN7 (MIC) is vacant or

with +5V high level. 3KHz

LPF filter existed in audio

channel.

⑩

RXD

(MODEM)

Theserialdataisinputtomodem

through this pin. Default is RS232.

Thehardwareisoneof

RS232, RS485 or TTL/5V

when delivery.

⑪

TXD

(MODEM)

Serialdataisoutputfrommodemvia

this pin. Default is RS232.

Thehardwareisoneof

RS232, RS485 or TTL/5V

when delivery.

⑫

CD_OUT

(MODEM)

Logical level output to indicated

whetheracarrierornot.Lowleverfor

carrier, high level for no carrier.

⑬

No connection

⑭

GND

Ground

⑮

No connection

Antenna installation

Fasten the antenna to the radio by turning the antenna connector clockwise into the

receptacle on right of radio when looking at front of radio.

Powering the Data Radio

SD-270 accepts variable s o u r c e s o f D C p o w e r t o p e r m i t m o r e v e r s a t i l e u s e . T h i s r a d i o

o p e r a te s f ro m 9 . 6V to 1 6 V DC a n d s t a n d a rd v o l t a ge f o r te s t ing i s 1 2 V D C . T h e 4 th pin

of DB15 female connector is the power input pin.

SD-270 Series Function

Channel Spacing

Theradioiscapableofprogrammablechannelspacing,having12.5KHzor25KHz

channel spacing.

SQ (Squelch) Level

Six SQ leve ls are set in the radio and can be selected by PC software.

The audio signal will continuously transmit. Levels are shown as below:

Level 0 is for fully open mute.

Level 1：0.15uV

Level 2：0.25uV

Level 3：0.35uV

Level 4：0.45uV

Level 5：0.55uV

CTCSS/DCS

To help block out unwanted calls to your radio, the SD-270 can be programmed to

set CTCSS/DCS code. When enabled, receiver can only receive RF signal with the

sameCTCSS/DCScodeofthetransmittertoavoidinterference from unwanted

signals. For fast lock times, the CTCSS/DCS is not recommended for high speed data

transmission.

Channel Scan

The radio enables to detect the channels by initiate scanning mode. Scanning mode

is optional and programmable. Four scan modes are provided as shown below:

0 ---------normal scan with carry only

1 ---------normal scan, Carry with tone

2 ---------priority scan, Carry only

3 ---------priority scan, carry with tone

Channel Select

16 channels can be selected by inner dip (4) switch (HW)onpowerboardorserial

command inputted from our PC s o f t w a r e ( SW). Only in SW control mode, channel

can be selected by PC software in “Channel” feature.

Channel Dip Sw i t c h Chart

TX Protection

This feature, when enabled, limits the amount of time that the radio can

continuously transmit for p r o t e c t ing theradiofromblockofthechanneland

damageonradiowhichiscausedbysustained transmission. In TX mode, if PTT is

effective all through and exceed set time, radio will stop transmitting automatically

until restart the PPT again. The time is set by programming.

V o l u m e

The radio output voice via SPK Pin with 10 vo lume levels. The choice of appropriate

This manual suits for next models

Table of contents

Popular Radio manuals by other brands

EisSound

EisSound KBSound iSelect user manual

Midland

Midland 1001LWX owner's manual

Konig

Konig HAV-SR41 manual

Roberts

Roberts exprssion manual 

VDigi

VDigi DD3.0 Operation manual

Radio Shack

Radio Shack 21-1863 owner's manual

Roberts

Roberts Stream 207 instruction manual

Sony

Sony Walkman SRF-M97 Service manual

Stanley

Stanley FatMax FMC770 manual

auna

auna DAB-Radio 10026947 manual

SOUNDMASTER

SOUNDMASTER UR190 instruction manual

HYT

HYT TC-320 user manual

auna multimedia

auna multimedia Yellowstone 10026851 instructions

B-Tech

B-Tech GMRS-V2 manual

Weierwei

Weierwei VEV-V8 user manual

SOUNDMASTER

SOUNDMASTER DAB750 instruction manual

Telefunken

Telefunken TF-1505 instruction manual

Makita

Makita LXRM03 instruction manual