The 8901-02 transmitter sends a signal down the sheath of a fiber optic cable
The 8901-02 transmitter sends a signal down the sheath of a fiber optic cable and the receiver then translates the electromagnetic field into a path and depth location.
The transmitter is permanently installed at the central office or regeneration station. The unit may be equipped with either 19" or 23" rack mounting brackets. The transmitter is designed to operate off a -48 VDC supply voltage. Every transmitter order includes the custom programming required to meet your unique application. The use of an EPROM chip in the transmitter makes it simple to install a new custom programmed chip to meet your changing needs. The 8901-02 Fiber Optics System was the pioneer in direct field-to transmitter remote control operation. Field access is achieved through DTMF keypad tones from a telephone or a two-way radio. Microprocessor controlled circuitry allows for remote access with either a four-wire or standard two-wire telephone line.
Each transmitter has a switch-settable DTMF access code. When being accessed via a two-wire telephone line, the transmitter allows 45 seconds for entry of it's individual access code. If the transmitter does not receive a code or receives invalid codes, it will go off-line at the end of 45 seconds to prevent tampering. If the transmitter receives a valid access code, it is then ready to receive DTMF codes to access it's many functions. If the transmitter is installed on a four-wire telephone system, the unit remains on at all times listening for it's access code. The 8901-02 provides a synthesized voice response that verbally confirms each DTMF command.
Four Frequency Selection
Four different frequencies can be programmed into the EPROM chip. Any frequency in the range of 128Hz to 10kHz can be programmed. Any low frequency portable receiver operating within this range can be used with the 8901-02 transmitter. RYCOM recommends the 8875 model receiver because it is highly sensitive with 126dB gain and a excellent noise filter, which eliminates misleading 50-60Hz power line indications.
A morse code signal can be sent down the cable at pre-programmed intervals. The Identification code is picked up by the receiver, audibly identifying your cable in crowded areas. Wildcard Command
The EPROM chip is programmed to perform each start-up function individually, or as a series of commands by using a single wildcard command.
Line Protection Devices
When the Line Protection Devices are installed between sheath and hard grounds, the 8901-02 can achieve up to 60 miles of tracing distance.
Remote Line Output Relay Control
Located at the cable entrance to the building, the Relay Control provides a hard ground when the tracing signal is off. When the tracing signal is on, the Relay removes the cable sheath from the ground. It connects to the transmitter, and allows the Line Protector to provide foreign voltage and transient energy limiting.
Rycom Instruments, Inc., 9351 E 59th Street, Raytown, MO 64133-3895. Tel: 816-353-2100; Fax: 816-353-5050.