The main components of the RT9000 unit are: a full duplex synthesized VHF/UHF radio with adjustable RF power from 1 to 20 Watts, a 6 or 5 cavity duplexer, a microprocessor controller board, an optional 4 channel expansion board, and an optional 110/220Vac or 24/48Vdc to 12Vdc internal power supply.

Designed and manufactured to telephone carrier industry standards, the RT9000 radio complies with Industry Canada (formerly DOC), FCC and CCITT regulations.

Standard Features of the RT 9000

• One Voice channel supporting 14.4kbs Fax or up to 28.8kbs Internet connections
• Identical field programmable Subscriber and CO units
• 4 Wire E&M operation
• Microprocessor controlled with self diagnostics and alarms
• 3825Hz out of band FSK signaling
• User activated compander to reduce noise during voice calls
• User activated scrambler for secure communications
• PC or handset programmable RF channels and user ID,
• Two digit signal strength indication from 1 to 32 µV in 1µV steps
• Bar graph signal strength in 6dB steps
• RS 232 port for diagnostics and software downloading
• Compatible with rotary or DTMF (pulse) dialing
• Transparent to payphone signals and line reversal
• Transparent to 12/16 kHz SPM (Subscriber Pulse Metering)
• Transparent to Coded Ringing and caller identification signals.
• Voltage transient and lightning protection of telephone line and power supply
• Subscriber automatic number identification - ANI
• Over-voltage line protection

Optional Features of the RT9000

 

Dual Tx/Rx continuous tone coded sub-audible squelch (CTCSS) to reduce interference from co-channel users

Diagnostics, alarm and link polling (with optional alarm board at CO unit)

Dual 12 or 16kHz subscriber pulse metering signals (SPM) and line reversals for payphone applications (with optional SPM chip)

Built in 110/220Vac to 12Vdc power supply with trickle charge for an external battery

Built in 48Vdc to 12Vdc converter for Central Office operation

Operate up to 4 private-line subscribers (with optional 4-line concentrator board at CO unit)

 

System Configurations

 

The operating parameters of the RT9000 unit can be programmed by a combination of 8 "on-off" DIP switches located on the controller board and software downloads into the EEPROM through the RS232 port or via DTMF commands from the telephone set. There are two types of programming modes, namely: "Progmode" that is permanently stored in EEPROM and "Techmode" that is only temporary and is reset to the default values when the radio is powered up again. Progmode and Techmode are restricted operations and are usually only accessed by technical personnel after a security access code is entered. There is also a limited number of user-activated DTMF commands such as turning on-off the compander and scrambler features.

The following lists the different system configurations that the RT9000 can be programmed for:

2-wire single channel

• 2-wire single channel with 4-line concentrator
• 4-wire E&M single channel
• 4-wire E&M link radio
• Repeater
• Payphone with line reversal or SPM

Central Office Unit

When the RT9000 unit is configured as a CO unit and is connected to the tip and ring of the CO exchange telephone line, the exchange interprets the RT9000 unit as a telephone set with two states (on-hook and off-hook). In the standby mode, the unit is in the on-hook state, its transmitter is off and the line coming from the exchange is connected to a high impedance ring detector circuit. In this configuration, the CO unit performs the following functions:

Detects ring frequency between tip and ring and transmits this information together with the corresponding subscriber ID via FSK signaling to the subscriber unit

Detects line reversal and 12/16kHz SPM pulses for payphone applications and transmits this information via FSK signaling to the subscriber (payphone) unit

Decodes the ID and off-hook state of the remote subscriber unit and seizes the telephone line corresponding to the calling subscriber

Decodes pulse dialing from the subscriber unit and activates the pulse dial relay

Decodes scrambler/compander codes from the subscriber unit and actives the corresponding scrambler/compander

Subscriber Unit

When the RT9000 unit is configured as a subscriber unit and is connected to the subscriber’s telephone set, the telephone interprets the RT9000 unit as a CO exchange. In the standby mode, the unit is in the on-hook state and its transmitter is off. In this configuration, the subscriber unit performs the following functions:

• Decodes the subscriber ID and ring information from the CO unit and generates a ring voltage to activate the telephone ringer
• Transmits a connect signal (subscriber ID) to the CO unit when the subscriber goes "off-hook"
• Transmits pulse dialing information as FSK format
• Decodes and duplicates 12/16kHz SPM pulses from the CO unit for payphone applications
• Decodes a line reversal from the CO exchange and duplicates it at the subscriber’s end
• Generates a constant 30mA line current (18mA for low power applications) to operate the subscriber telephone set

Signal Strength Meter and Faults

The front panel of the radio has two sets of LED’s and a 2-digit display for signal strength indication. The first set of 5 LED’s provide indication of signal strength and light up in increments of 6dB.

The 2-digit display provides an indication of the signal strength from 1 to 32µV in 1µV steps. In normal operating mode the display indicates signal strength and in "Techmode", the display indicates the last activated function.

The other set of 4 LED’s provide status indications of "ON", "Tx" (transmit), "COR" and "Fault". Whenever the microprocessor detects a malfunction of the radio operation, the "Fault" LED comes on and a fault code is activated on the 2-digit display. The following fault code indications are provided:

• EB Low battery alarm, if battery is below approx. 10.5Vdc
• EF Receive frequency out-of-lock
• EE EEPROM checksum failure, EEPROM corrupted or accidentally erased
• EC Main program checksum failure
• EA RAM checksum does not match, unit resets and reloads information from EEPROM

Link Polling (optional)

 

An optional alarm board can be installed at the CO unit to provide two alarm indications: one for link failure and one to indicate that the Subscriber battery is low. With the alarm board installed, the CO polls the subscriber radio once every 3 hours to verify its integrity. This integrity check is also performed at the end of each ring cycle on a land line call. The CO unit is equipped with a set of dry contacts on the DB15 connector or on a terminal block when mounted inside the weatherproof housing to signal a radio link failure.

In case the battery voltage drops below 10.8V, the subscriber is warned by means of an audible tone that is generated at the subscriber’s unit. The alarm condition is also provided at the CO unit by means of dry contacts. The alarm condition will revert to normal when the subscriber’s battery voltage is restored.

 

Accidental Off-Hook

The subscriber radio reverts to sleep mode if no DTMF or pulse dialing occurs for 30 seconds following an off-hook detection. The accidental off-hook mode reverts to normal operation when the telephone is placed on-hook again thereby preventing unnecessary power consumption.

 

Current Saving Feature

 

The RT9000 features a current saving operation which drastically reduces standby current requirement. For minimum power consumption, the microprocessor of the RT9000 unit operates in a sleep mode where it checks every few hundred milliseconds for activity on the radio channel or on the telephone line. If it detects any change, it wakes up and activates all other circuitry. The average idle current consumption is the sum of the current in sleep mode plus the current during the time where it checks for activity, multiplied by the respective duty cycle. This way, a very low idle current can be achieved, typically 15mA for a 10 to 1 duty cycle for the 1watt version.

 

Optional Accessories

• Built in RPX-912 Power Supply 220/110Vac/12Vdc
• Built in RPX-924 Power Supply 24Vac/12Vdc
• Built in RPX-948 Power supply 48Vdc/12Vdc
• Four channel extender board for four private line concentrator operation
• Alarm board, provides dry contacts in case of link failure
• 6 element 9dB gain Yagi Antenna
• RG 213 coaxial cable
• Coaxial connectors for antenna mounting
• Stainless steel out door cabinet
• Solar panels
• Standby battery

Power Supplies

 

For maximum system performance, it is important to choose a power supply capable of providing a hum and noise free 13.6Vdc voltage, <50mVpp.

To operate the RT9000 radio telephone unit at 20watts RF output, a 13.6Vdc power source rated at 8A continuous duty is required. At 1 to 10watts RF output, a 13.6Vdc power source rated at 5A continuous duty is required.

Various power supplies for operation on 110/220 Vac or 24/48 Vdc are available from RF-TEL. All power supplies have a dc input for connecting a stand-by battery. During stand-by, the battery is trickle charged and will switch over to the radio in case of a power failure without interrupting a call. The RF-TEL power supplies are of a high efficiency switching regulator type dissipating very little power, offering noise free operation of the radio system.

Programming the RT9000

 

The RT9000 can be programmed either from a telephone set or via the RS232 port.

There are two types of programming, Progmode programming that is permanently stored in EEPROM and Techmode programming that is temporary and is reset to the default values when the radio is powered up again.

An 8 position DIP switch located on the controller board allows the radio to be configured for:

• Subscriber operation
• Central Office operation
• 4 Wire E&M operation
• Repeater operation

Programming from a PC

Personalities are stored in EEPROM and become the default mode of the radio on power up. Personalities can be programmed via RF-Tel’s programming software on a graphic layout page and downloaded to the radio via the RS 232 port. Most of these parameters can also be changed directly from a DTMF telephone using the appropriate security access code.

• Transmit frequency
• Receive frequency
• CTCSS Tx frequency
• CTCSS Rx frequency
• Scrambler on / off default can be selected
• Compander on / off default can be selected
• Current saving enable / disable
• Repeater mode
• Subscriber ID
• Access code for programming mode
• Access code for techmode
• Customer Name
• Diagnostic mode
• Auto SPM pulse
• 4 Wire E&M
• 1st ring duration (used for caller ID function)
• Transmitter control, on/off
• Front end filter tuning
• Transmitter output level
• Reference oscillator tuning
• 1000 Hz test tone generation
• Generate ringback

User Programming

User programming allows the Subscriber to activate or de-activate the compander and scrambler from his telephone after a connection has been established.

When going off hook, the radio will initially come up in the default mode (compander on, scrambler off) established in personality programming.

To activate the compander, the user dials #*11, to de-activate the compander he dials #*10.

To activate the scrambler, the user dials #*61, to de-activate the scrambler he dials #*60.

A double audible beep indicates to the user that the function selected has been activated, a single audible beep confirms that the function has been de-activated. When going on hook, the radio system reverts to the default mode.

RT 9000 Manual in PDF format