Fact is that the Nixies need a particular cathode current to entirely light up the cathode at all. If you just reduce the anode voltage the current through the anode resistor drops and so does the cathode current. Up to a certain point where the cathode is only partially covered with the discharge glow - or doesn`t come on at all. Both is not what
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we wanted, right So here is my approach that is a bit more complicated but seems to work fine. At least for my taste better than just reducing the anode voltage. Your individual mileage may vary however. The circuit shown above is a simple oscillator with a 555 chip. The only uncommon part of the layout is the 1M Ohm Potentiometer and the two diodes. This part of the circuit allows to vary the duty-cycle of the output signal between 5 and 95 percent. The transistor in the upper part is wired into the high voltage supply line between power supply and the nixie anode resistors. The 555 is driving another transistor that simply cuts off the voltage on the base of that "main" transistor. Result: the lower the duty cycle of the 555 output signal, the longer is the conductive period of the main transistor - during which the full current flows through the anode resistors. The trick is, that the high voltage is switched and not regulated. The component values in the schematic allow a frequency variation between 3 - 8. 5 ms (about 117 - 330 Hz) and the best results with a set of ZM1080s is at about 3. 5 ms (285 Hz). Here the regulation of the duty cycle works from 5 to 95 %, where 95% is pretty dim, but still readable and the cathodes fully covered. The transistors must be any of the high voltage types, since it is either attached to the HV-supply or has to sink the base voltage of the main transistor. For my prototype I picked 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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