This modification is to be done AT YOUR OWN RISK and there is no guarantee that the modification will work for you. Failure to properly install this design correctly may result in damage to you and/or your laserdisc player. This web site takes no responsibility for any modification you may attempt. The following shows a step-by step description on
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how I modified my Pioneer CLD-1950 laserdisc player to output the Dolby* Digital (AC-3) RF signal needed to drive Dolby Digital demodulators/decoders. My intention is to help those interested in modifying their own player; thereby avoiding the cost of upgrading to a new machine or paying a large sum of money to services that provide the Dolby Digital modification. The custom board shown here holds the required AC-3 circuitry. Once installed, the card enables older, non-AC-3 laserdisc players the ability to output the much talked about AC-3 RF signal. The circuit I used came from Kevin`s web page. Instead of the 2SA1037K and the UN2112 I used the BC808, which is available in Europe. This made it necessary to add a pullup from the base of Q2 to +5VDC, and a series resistor from the same base to the mute input of the board. I used 22k for each resistor, the value is not critical though. This version of the board uses metal film surface mount resistors as well as surface mount ceramic capacitors and transistors to minimize the level of noise in the signal. Players which have the AC-3 circuitry from the factory, typically use surface mount components as well. The card was constructed using a printout from the circuit board program I have written myself. The new circuit card needs two voltage forms (+5VDC, -5VDC) and a ground. Power is tapped from these three lines as indicated in the photo. Red carries the +5VDC; Yellow carries...
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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