The first 5 circuits described in the following sections were reverse
engineered from commercial HeNe power supplies. There may be errors in
transcription as well as interpretation. In many cases, the transformer
secondary voltage was not marked and where the actual hardware was not
available for testing, an estimate of its value was made. Many of these designs are quite old since modern commercial units tend toward
inverter designs since they can be more compact and have higher efficiency.
Unfortunately, these are nearly always potted in Epoxy and impossible to
The last one I built using the scrounged power transformer from a long dead
and cannibalized tube type TV and a pair of high voltage capacitors (for the
main filter on the doubler) that had been sitting in a box minding their own
business for the last 15 years. My total cost for the remaining components
was about $5.
AC Line operated power supplies will drive HeNe tubes just as well as fancy
inverters and are somewhat easier to construct and troubleshoot.
The line side circuitry is not shown for any of these. See the section: "AC
input circuitry for HeNe power supplies" for details.
Edmund Scientific HeNe power supply:
There were some inconsistencies in the component values of this circuit when
I first saw it. I have adjusted the RMS value of the transformer down from
710 to 650 VRMS so that the numbers work out closer to what one would expect.
Estimated specifications (Edmund Scientific):
* Operating voltage: 1,700 V.
* Operating current: 4 mA.
* Starting voltage: around 5,300 V.
* Compliance range: NA - no regulation.
(Portions from: Steve Nosko (email@example.com)).
The 650 V transformer output feeds a voltage doubler (D1 to D6 and C1 to C4)
resulting in about 1,750 V across all the electrolytics. (Slightly less than
2 times the peak value of 650 VRMS.)
D7 to D12 and C5 to C7 form a classical voltage multiplier ladder which
generates a peak...
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.....
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to....