GB2166928A - Extra low frequency long range wireless signalling/paging pulse sending apparatus - Google Patents

Abstract

This signalling apparatus, by being a stored energy quick discharge pulse system, enables a series of high power pulses to be obtained from only a very small average power input. This signalling apparatus as well as for long range communication can also be adapted for local uses, such as mines or any other underground activities, by using lower pulse voltages and smaller antenna dimensions to restrict the range. <IMAGE>

Description

SPECIFICATION Extra low frequency long range wireless signalling/ paging pulse sending apparatus This apparatus when used with the extra low frequency uninsulated underground antenna as described in patent application No. 8311247 enables reliable long range E.L.F. wireless signalling. As this is a pulse system average power requirements are very low and selective paging is possible with receivers sensitive to the rhythm of the pulses.

The principle of operation is as follows; A high voltage direct current power unit charges up a large high voltage condensor. After a pre-determined period, the timing control device closes a suitable set of contacts (e.g. Thyristors) connecting the charged condensor directly to the terminals ofthe E.L.F. antenna. The very low impedance of the antenna causes an extremely large current pulse to be drawn out ofthe condensor and thence to radiate outwards from the antenna. The timing control device then re-opens the contacts allowing the condensorto recharge from the power unit and after a predetermined period recloses the contacts, to repeat the cycleforasmanytimesasthemasterhand key remains depressed.

If the timing device is setfor a very fast rhythm and the direct current power supply converted into a heavy duty unit, an effectivejamming equipmentforthe E.L.F./L.F. spectrum would exist.

1. Toobtaintheveryhigh powers needed for long range extra lowfrequency signalling, a stored energy system comprising of a charged large high voltage condensorthat is quickly discharged into the earth or sea is proposed. This is best done via the underground/undersea antenna as described in Patent application number8311247.

2. This broadband signalling apparatus could however be used with any conventional overground aerial with the appropriate senderto aerial matching circuitry.

3. This high power pulse system needs only a very low average power input.

4. The pulses can be suitably spaced for selective paging or codes.

5. Local sending for mines and other underground activities can easily be achieved by using lower voltage pulses and reduced antenna dimensions.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Extra low frequency long range wireless signalling/ paging pulse sending apparatus This apparatus when used with the extra low frequency uninsulated underground antenna as described in patent application No. 8311247 enables reliable long range E.L.F. wireless signalling. As this is a pulse system average power requirements are very low and selective paging is possible with receivers sensitive to the rhythm of the pulses. The principle of operation is as follows; A high voltage direct current power unit charges up a large high voltage condensor. After a pre-determined period, the timing control device closes a suitable set of contacts (e.g. Thyristors) connecting the charged condensor directly to the terminals ofthe E.L.F. antenna. The very low impedance of the antenna causes an extremely large current pulse to be drawn out ofthe condensor and thence to radiate outwards from the antenna. The timing control device then re-opens the contacts allowing the condensorto recharge from the power unit and after a predetermined period recloses the contacts, to repeat the cycleforasmanytimesasthemasterhand key remains depressed. If the timing device is setfor a very fast rhythm and the direct current power supply converted into a heavy duty unit, an effectivejamming equipmentforthe E.L.F./L.F. spectrum would exist. CLAIMS

1. Toobtaintheveryhigh powers needed for long range extra lowfrequency signalling, a stored energy system comprising of a charged large high voltage condensorthat is quickly discharged into the earth or sea is proposed. This is best done via the underground/undersea antenna as described in Patent application number8311247.

2. This broadband signalling apparatus could however be used with any conventional overground aerial with the appropriate senderto aerial matching circuitry.

3. This high power pulse system needs only a very low average power input.

4. The pulses can be suitably spaced for selective paging or codes.

5. Local sending for mines and other underground activities can easily be achieved by using lower voltage pulses and reduced antenna dimensions.