THE 'MINDA' RECEIVER RX-400.
Each 'MINDA' receiver can display two status indications from up to four different transmitter
units, coded 1-4 and all operating with the same group code. Pressing the RED button on a 'key-
fob' style transmitter should light the Red LED on the receiver, whilst the BLACK one lights the
Green LED.
Operation
The receiver is very easy to use, and has two modes of operation, 'SILENT' and 'BEEP'. If the
'BEEP' mode is selected by moving the On/Off switch in the direction away from the eight LED's,
when a 'wanted' signal is received the appropriate status LED will light and an audible pulsed
tone alarm will be heard. The tempo of this pulsed tone is faster for a 'Red' alarm than for a
'Green' alarm, thereby facilitating the aural identification of 'Urgent' and 'Non-Urgent'
transmissions.
When 'SILENT' mode is selected by moving the On/Off switch towards the eight LED's, the
appropriate LED will still light but all audible tone signals are inhibited. Silent signaling will be
provided by means of a built-in vibrator.
Whenever the receiver is initially switched on, all of the eight large LED's will be briefly
illuminated, in pairs, to provide a 'lamp-test' and give visual confirmation that the microprocessor
is operating correctly. The small red LED adjacent to the On/Off switch will then flash regularly as
long as the receiver is operating but not receiving any signals. As soon as the receiver detects a
signal the red LED will light continuously. BE AWARE that any signal received will cause this to
happen, whether it is local electrical interference, a transmission with a different group code, or a
'wanted' signal from a transmitter on your own group code.
Briefly pressing the 'Reset' button will cancel any audible alert, initiate a 'lamp-test' (see above)
and extinguish any LED's that may have been illuminated prior to resetting.
Additional alerts provided
1. Transmitter Low-Battery alert.
A valid transmission received from a transmitter with a weak, but not completely flat, battery will
cause the appropriate LED indicator on the receiver to 'blink' out briefly about once per second.
This will indicate to the operator that that particular transmitter should have its battery replaced at
the earliest opportunity.
2. Receiver jamming alert
Any signal received on the frequency will cause the receiver to lock-on, whether it is local
electrical interference, a transmission with a different group code, or a 'wanted' signal from a
transmitter on your own group code. However, if the 'MINDA' receiver is 'jammed' by a continuous
unrecognized signal, then after a short period of time (set during manufacture to 5 seconds, but
re-programmable) it produces a series of audible 'beeps' to alert the user and enable him to move
to an interference-free location. As soon as the interference clears the 'beeps' will cease.
More about the Battery Economizer
The battery economizer operates by switching the receiver on for a very brief period, looking for a
signal, and if nothing is found switching it off again. If a signal is found, the receiver 'locks-on' for
long enough to process and display any alarm signal that may have been received. The small red
LED adjacent to the On/Off switch displays the status of the battery economizer circuit. While the
receiver is in the pulsing 'standby' mode it is, in fact, switched on for less than two percent of the