904L Four Channel Receiver
The Model 904L is a 4 channel receiver for use in the security industry. The Model 904L has 4 independent channel relay outputs. Transmitters are assigned channels and loaded into receiver EEPROM using a “TEACH” function. All transmitters send battery status when activated and there is a receiver output dedicated to monitoring this function. When the DW-101A transmitters are used, the transmitters may be configured such that the receiver output follows the status of the transmitters assigned to a particular channel in the same manner as if the circuits activating the transmitters were a nommally closed loop. The receiver output restores only when all the transmitters have been restored.
Use the part no.'s below when making purchase orders to Alarm Electronics. Please see the Sales page for terms.
- 904L (Four Channel Receiver)
- Operating Frequency - 300mhz
- Outputs - N/C relay contacts
- Contact Rating - 1 amp resistive load
- Power Input - 12VDC
- Current Standby - 15ma
- Max Current - (all relays active) 140ma
- Low Battery Output - Solid state switch to ground via 220ohm resistor
- Decoder Data Output Source Impedence - 3.3K
- Trans. Code Memory Capacity - 30
- Size - 4.75" x 2.2" x 1.4"
- Main Input/Output Connection - 10 Term Strip
Auxiliary output low battery & Data-4 conductor cable DATA OUT: when using an additional channel decoder(s) connect this data out line to the data input lines of the decoder(s). Up to 6 decoders of any type may be connected to expand the number of available zones.
The LOW BATTERY output is momentary and occurs at the same time as the channel output activation (either alarm or restore). The Low battery output is a solid state switch to ground with a current limiting resistor in line (220 ohms). On some control panels where one side of the zone is common with the (-) side of the power input, this output may be connected to the positive side of a panel zone with an end of line resistor across the zone. This will cause an alarm condition by shorting out the zone (normally open operation). If only local indication of low battery is needed, a small audio buzzer may be connected between this output and the (+) 12 volt power. If a low battery condition exists, the buzzer will sound each time the transmitter is activated.
If you have a version of 902L with a wire antenna and it is desired to remote the antenna, RG59 co-ax cable may be used by carefully soldering the co-ax to the antenna port. Using a soldering iron, carefully remove the existing antenna and solder the center conductor of the co-ax to the antenna point and the shield to the nearby brass ground plane.
The remote antenna should be 10 inches in length with an associated ground plane. If possible, mount the antenna in the vertical position clear of metal objects.
The 904L has an open field range of 600 to 800 feet without obstructlons or RF interference. Inside buildings where there is metal or other reflective objects and obstructions, the peak range is decreased considerably.
When using with DW-101A Transmitter
When using the DW-1O1A transmitter(s) in the SUPERVISION mode with the 904L reciever if the RESTORE transmission from the transmitter is missed for some reason then the zone will be in the alarm state even though the opening is restored. To restore the zone simply open and close the opening(s) associated with that particular zone. If this is a persistant problem it may indicate that the range is marginal and the reciever may need to be relocated for more reliable reception.
The 904L is compatible with all Smart-Wave™ transmitters.