The following is a layout of my repeater system and what was needed to get it on the air. The ILink system was designed by Graeme, M0CSH, and I take no credit for its success. The circuit below is only required by repeater control stations (sysops) and not by the average PC user of ILink. This information is only provided to help other amateurs li
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nk their repeater to the ILink system. The link receiver consists of a separate Hamtronics R301 VHF receiver with the Hamtronics TD-5 subaudible tone decoder. The VHF receiver is tuned to 147. 240 MHz and receives the repeater activity off-air. Whenever there is activity on the 147. 240 repeater COR, the repeater generates a 77 Hz subaudible tone which in turn un-mutes my link receiver. The link transmitter consists of a separate hamtronics T304 UHF transmitter which sends link audio to the repeater via a UHF link. Whenever the link COR is active at the repeater, the 77 Hz subaudible tone is disabled to prevent a feedback loop into my link system. The UHF link is voted at the repeater and its priority is set very low. This allows any 2 meter activity to override the link which in turn gives us full control of the link system. This is the layout of my iLink board. When building this board, I used screw terminals for all of my external connections. I find this dresses up the board nicely, and makes it very convenient when testing the circuit out; there is no need to solder and unsolder connections. The circuit is build on perf board which was purchased from Radio Shack. A lot of my projects are down with perf board due to the time saved in laying out a board. Also, perf board is easy to work with if there is a time when I need to make a modification to the circuit. The ILink circuit was designed by Graeme, M0CSH. I drew up a...
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....
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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....
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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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