The common wiring method had one side of the line cord going to a pin on the rectifier tube and the other side going to one terminal of the on/off switch. The other terminal of the on/off switch went to chassis. Suppose you plugged it in so the chassis was `cold` when the radio was turned on. That would mean that the bottom prong of the plug was c
Click here to download the full size of the above Circuit.
onnected to the power line neutral. Everything would be fine until you turned the radio off. Now the top prong of the plug is connected to the hot side of the power line. The tube heaters are cold and have a very low resistance (very approximately 100 ohms). This resistance is connected from the hot side of the power line to the chassis of the radio. You could connect a clip lead from the radio chassis to a water pipe and the radio would come on and play. If part of your body should complete the circuit instead of a clip lead you might never play again. Before starting to modify the radio go to a discount store and buy a polarized 2 prong plug extension cord. They are usually a dollar or less. Cut away the old power cord but leave short pieces of it on the rectifier tube and switch. If the insulation is in good shape (not always the case in these old sets) leave enough wire to reach to the switch. If the insulation on the old cord is rotten replace it with a piece of wire cut from the extension cord. Decide how long you want the new cord on the radio to be and cut the cord that length from the plug end. You will most likely never find a use for the socket end so cut off the extra cord, save it, and throw the socket end away. Thread the new cord in through the chassis hole. Position the end of the cord near where it is to be connected, the on/off switch and rectifier tube. Leave enough extra to be sure it will be long enough...
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.....
characters left: