DE948308C - Audio frequency remote control receiver - Google Patents

Description

Audio frequency remote control receiver For remote control of so-called Network command systems are known to various methods, the recipient in each case are trained in accordance with the procedure. Mostly it is for the execution of the various commands in the manner of rotary selectors, a number of switching contacts are available, and the rotary knife is driven by a magnet (as with a voter) or - and this is likely to be the case in the majority of cases - by means of a synchronous motor.

What all procedures and all recipients have in common, however, is the disadvantage that in the event of a mains voltage failure, both when using synchronous motors and Even with rotary selectors for executing the switching commands, no operational readiness or execution option is available.

It is already a remote control receiver for audio frequency systems has been proposed that an auxiliary voltage from a power failure switches on the battery present at the receiving location and thus allows commands to be transmitted. In contrast, the arrangement according to the invention does not require and requires no auxiliary voltage also no AC relay to monitor the mains voltage.

The subject of the invention is a simple arrangement, which allows in connection with receivers for each of the commercially available Systems or the most important switching commands and messages on their own even in the event of a power failure, such as B. Aircraft alarm, fire alarm and similar.

The audio frequency remote control receiver according to the invention is thereby characterized in that by a winding of its resonant circuit tuned to the transmission frequency the readiness for work established and he when the first arrives, after failure the. mains voltage incoming command pulse is put into action.

The extremely straightforward circuit consists of a polarized relay with two windings, one of which is used to monitor the mains voltage. When the normal mains voltage is present, the receiver of conventional design (or no receiver) is connected through a corresponding switching contact. If the mains voltage fails, the winding I of the relay is de-energized and the tongue of the relay moves to a central position, whereby the connection of the second receiver (according to the invention) is prepared. The coil II, which together with a capacitor forms an oscillating circuit tuned to this frequency, is only excited when additional impulses or a continuous tone of the frequency characteristic of the network command system arrive. In the case of resonance, and with appropriate design also in the vicinity of the resonance point, a relatively high voltage of about 30 volts occurs on this resonant circuit, which is easily enough to excite winding II of the relay. This means that either an auxiliary circuit (with a battery) available at the receiving location can be switched or, if the oscillating circuit is appropriately adapted (at the terminals of which a relatively high voltage occurs in the case of resonance), a highly sensitive loudspeaker, also tuned to the corresponding frequency due to its dimensions, through the loudspeaker provided by the The audio frequency transmitted from the commanding authority can be operated.

If there is an auxiliary circuit with its own voltage source, it is possible to transmit pulse series or any desired pulse sequences to carry out remote communications or remote control commands. In the absence of an auxiliary voltage source, the audio frequency that is specific to the network command system - or changes in this frequency in one area (howling) - can be transmitted directly in the connected loudspeaker with a good room volume (without amplifier). As is well known, a power of 0.3 watts is sufficient for a commercially available loudspeaker to fully excite and achieve room volume.

Instead of the loudspeaker it would be one with the interposition of one Transformer, the secondary side of which is provided with rectifiers, also possible, convert the audio frequency into DC pulses and using a cook-sensitive Relay chain, even without an auxiliary voltage source, in the event of a power failure directly via the Network pulse series or any desired pulse trains for the transmission of commands or To transmit remote control measures.

Claims (3)

PATENT CLAIMS-i. Audio frequency remote control receiver for command transmission in the absence of mains voltage, characterized in that its The resonant circuit tuned to the transmission frequency is ready for work and when the first command pulse arrives after the mains voltage has failed is put into action. 2. Audio frequency remote control receiver according to claim i, characterized in that in the presence of an auxiliary circuit through a Relay the reception and transmission of pulse trains and pulse series to a downstream Relay switching is made. 3. audio frequency remote control receiver according to claim i, characterized in da.ß the incoming control command - in the absence of an auxiliary voltage source at the receiving location-is given directly to an adapted loudspeaker and thus an acoustic signal sounds. q .. audio frequency remote control receiver according to claim i, characterized in that in the absence of an auxiliary power source at the receiving location the audio frequency commands transmitted by the network command system, with the interposition of a transmitter or similar link, are used after rectification to control a relay chain. Publications considered: German Patent No. 930 075.