A field strength meter is a very handy tool for locating a transmitter. A sensitive field strength meter by itself has some limitations, however: It will respond to practically any RF signal that enters its input. This property has the effect of limiting the effective sensitivity of the field strength meter, as any nearby RF source (or even ones f
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ar away, if the meter is sensitive enough. ) will effectively mask the desired signal. This property can be mitigated somewhat by preceding the input with a simple tuned RF stage and, in most cases, this is adequate. A simple tuned circuit does have its limitations, however: It is only broadly selective. A simple, single-tuned filter will have a response encompassing several percent (at best) of the operating frequency. This means that a 2 meter filter will respond to nearly any signal within to the 2 meter band. A very narrow filter can be tricky to tune. This isn`t usually too much of a problem as one can peak on the desired signal (if it is close enough to register) or use your own transmitter (on a nearby frequency) to provide a source of signal on which the filter may be tuned. An obvious approach is to use a receiver. While many receivers have "S-meters" on them, very few of them have meters that are truly useful over a very wide dynamic range, most firmly "pegging" even on relatively weak signals. While an adjustable attenuator (such as a step attenuator or offset attenuator) may be used, the range of the radio`s S-meter itself may be so limited that it is difficult to manage the observation of the meter and adjusting the signal level to maintain an "on-scale" reading. Another possibility is to modify an existing receiver and interface it with something like the Wide Dynamic Range Field Strength Meter - and that is...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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