Back cover removed showing the power supplies upper deck and the original Dayton 2C915A (220vac - 140cfm blower) mounted to the underside of the cabinet. The RF deck enclosure was removed. Upper deck of the power supply with the original blower removed. From left to right you can see the Filament transformer, HV filter cap in the rear, Bleeder resistors (back right) and the Relay/Control circuit
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transformer (front right). After a great deal of research and measuring, I chose a EBM G2E120-AR38-43 (click link for catalog - 1MB PDF file - see page 19) blower as a replacement for the Dayton. The new blower uses a split capacitor motor which is much easier to speed control by using a capacitor in series with one of the motor leads. Another advantage is the `External Rotor` design which places the motor in the center of the squirrel cage. The motor runs very cool. The EBM blower has a cast aluminum housing and zero maintenance ball-bearings in the motor. This picture shows the air switch mounted. Henry uses an air switch to turn on the tube filaments and relay power supply only when sufficient airflow is present to cool the tubes. End view showing the air vane attached to the air switch. The new blower has a much wider squirrel cage which allows it to move more air at a slower, quieter speed than the original Dayton blower. After dealing with all of the vibration problems of the original blower, I decided not to take any chances with the new one. After more research I found a company that makes small Anti-vibration Mounts ( Part # 62490-2 ) that were perfect for my application. Brad, K7ZSD, made the mounting plate for the new blower out of 3/16" aluminum plate. After further experimenting, it became obvious that an extension arm on the plate would be necessary to properly distribute the weight of the fan. Here`s a side...
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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