This design was created to overcome a problem I was having with the tailwheel doors of the P-51 Mustang. The problem was that the undercarriage sequence is complicated and would have required 2 independent sequencers. The closing sequence is: Main gear doors open, Tailwheel retracts, tailwheel doors close, main gear retracts, main gear doors clos
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e. The complication is the main gear doors close again after the main gear extends, but the tailwheel doors remain open. Additionally the tailwheel takes 2 seconds to close (electronic servo slow) and the pneumatics for the main gear is restricted to slow their operation. This design simply drives a servo to close the tailwheel doors once the tailwheel has retracted. It runs from the servo battery supply, but has no signal connection to the RX. When the tailwheel is almost completely retracted the wheel (or leg) closes a micro-switch. This circuit causes the door servo to move to the other end of its travel, closing the doors. almost as soon as the tailwheel starts to move the micro-switch is released and the doors open (almost instantly). The signal that the RX sends to the servos (in most systems) is pulses between 1 ms and 2ms long at a rate of 50 Hz. This design produces pulses to drive the servo directly. The schematic and Vero Board layout are (click for full size): The circuit is quite simple to construct, having few components and no particular handling problems with the components. Firstly cut a piece of Vero board the correct size and make the cuts in the tracks as shown. Insert the wire links and solder in place. I normally use PCB pins for the external connections (much easier to work with later) and if used insert and solder these. Fit the resistors to the board and solder. The NE555 is fitted in a socket and...
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....
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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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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....
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