JPH0523689B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a direction finder, and more particularly to a portable direction finder that can be used in mountains, ocean recreation, etc.

[Technical background of the invention and its problems]

Direction finders, compass magnets with scale rulers, and direction finders with compass magnets are each commonly commercially available individually.

If only a direction finder is used, even if the direction of a radio station whose radio wave emission location is known is known, the direction is not known, and in order to know the direction, another compass must be used together. Additionally, a protractor is required to mark the current location on the map, and a ruler with a scale is required to measure the distance to the destination, making it very inconvenient to carry.

Compass magnets with scale rulers are very convenient to carry, and are widely used because they allow you to see the direction of magnetic north and the distance on a map. However, when the target cannot be seen at night, in fog, or in a sea of trees, only the magnetic north is known, and the current position cannot be accurately estimated.

If you use a direction finder with a compass magnet, you can find magnetic north and the direction of the radio station, but you will need a protractor to mark your current location on the map. Furthermore, measuring distance requires a ruler with a scale, which is inconvenient to carry.

All of the above-mentioned methods have various drawbacks when used alone.

[Purpose of the invention]

The present invention was made in order to eliminate the above-mentioned drawbacks, and combines a direction finding receiver, a compass, and a scale ruler into an integrated unit, thereby providing both portability and usability. It was done for a purpose.

[Summary of the invention]

The portable direction finder according to the present invention is composed of a wireless direction finding section equipped with a ferrite bar antenna, a direction measuring magnet section, and a ruler section with a distance measuring scale provided parallel to the ferrite bar antenna. Place it on an expanded map, align the north of the map with magnetic north, and use the wireless direction finder to find the direction where the electric field strength is minimum. If the location of the radio station is known, the azimuth line segment can be found on the map from the location of the radio station and the detected azimuth. When two azimuth line segments are obtained for a plurality of radio stations whose transmission positions are known, the intersection of the two azimuth line segments becomes the observer's current position. Measure the distance to the destination using a scaled ruler.

There is one wireless station with a known transmission position and one azimuth line segment.
If all you have is a book, check the map for a clear target and find other direction lines. The intersection of the other azimuth lines obtained from the target and one azimuth line detected by radio becomes the observer's current position.

[Embodiments of the invention]

Hereinafter, one embodiment of the portable direction finder according to the present invention will be described in detail with reference to the drawings.

In FIG. 1, 1 is a portable direction finder. The portable direction finder 1 is composed of a thin radio receiver, and is provided with a volume 2, a tuning dial 3, and earphones 4 for receiving broadcast waves. Further, inside the main body, a ferrite bar antenna 4 is provided along the longitudinal direction as shown by the dotted line. The receiving sensitivity is maximum in the direction perpendicular to the ferrite bar antenna 4, and the receiving sensitivity is minimum in the parallel direction. Reference numeral 6 denotes a compass, which is installed on the surface 1a of the portable direction finder 1 so that its longitudinal direction corresponds to magnetic north. Further, a scale is engraved on the side surface 1b, so that when the portable direction finder 1 is placed on a map or the like, the side surface 1b becomes a scaled ruler 7 for distance measurement.
The unit of the scale is, for example, a scale of 1/50,000.

The portable direction finder 1 is placed on a map spread out on a flat surface, and the north of the map is aligned with the magnetic north of the compass 6. The azimuth line segment of the point where the electric field strength of a plurality of known wireless stations is the minimum is determined on the location of the wireless station. The user estimates his or her current position from the point where each of the extension lines intersects, and measures the distance to the destination using a scaled ruler 7 for distance measurement.

If there is only one radio station that can be received at the current location, check a clearly visible target on the map, and find the current location at the intersection of the azimuth line segment and the azimuth line segment from the radio station.

FIG. 2 is a perspective view showing another embodiment in which the surface 1a of the portable direction finder 1 is formed in a different arrangement. In the figure, 5a is an earphone jack. The parallel direction of the ferrite bar antenna (not shown) provided inside the main body is indicated by an arrow labeled DIRECTION.

In the embodiment, a radio receiver equipped with a ferrite bar antenna is used as a radio direction finding unit which is a means for measuring the direction of a radio station, but the present invention is not limited to this. Also, if you use a radio receiver that can receive regular medium wave broadcasts, you can receive weather forecasts, typhoon information, etc.

Further, although the horizontal directionality of the ferrite bar antenna installed in the radio direction finding section shows a figure 8 pattern, it is also within the scope of the present invention to equip a sense antenna to make the directionality heart-shaped. be.

〔Effect of the invention〕

The portable direction finder according to the present invention is composed of a wireless direction finding section equipped with a ferrite bar antenna, a magnet section for measuring direction, and a ruler section with a distance measuring scale provided parallel to the ferrite bar antenna. This has the effect of making it easy to estimate the current location on the map. Furthermore, with current circuit technology, it is possible to make the direction finder thinner and lighter by adjusting the dimensions to the desired scaled ruler for measuring distance, so it is possible to provide a direction finder that is convenient to carry and compact at a low price. Therefore, it can be expected to be applied to various leisure facilities, whether in the mountains or the ocean.

[Brief explanation of the drawing]

1 and 2 are perspective views showing an embodiment of a portable direction finder according to the present invention. Code in the figure, 1
is a portable direction finder, 2 is a volume, 3 is a tuning dial, 4 is a ferrite bar antenna, 5 is an earphone, 5a is an earphone jack, 6
is a compass, and 7 is a scaled ruler for measuring distance.

Claims (1)

[Claims] 1. A means for measuring the direction of a radio station using a ferrite bar antenna and a compass, a means for measuring magnetic north using a compass, a means for recognizing the azimuth line segment using a ruler with a scale set parallel to the ferrite bar antenna, and a method for measuring the direction on a map. A portable direction finder characterized by comprising: a means for measuring the distance of.