Circuit Project Electronic

12KV output HV supply

admin — Fri, 04 Jul 2008 08:56:48 +0000

Obtain flyback transformer with known good HV secondary winding. primary may be left intact if it is known to be in good condition - non shorted. A flyback removed due to failure may be used if it was the primary that failed and the primary turns can be removed without damaging the HV secondary or losing the secondary return connection! Flybacks fail in both ways (primary and secondary).

Read more original source:
http://www.ee.washington.edu/circuit_archive/circuits/F_ASCII_Schem.html#ASCIISCHEM_018

High Voltage from an Ignition Coil

admin — Fri, 04 Jul 2008 02:43:19 +0000

The peak output voltage will be approximately 15,000 to 20,000 volts, but this will vary with the ignition coil type and the voltage at which the MOV starts conducting. Do not touch any part of the 555 circuit including any leads of the timing resistors or timing capacitor; doing so can inject interference into the circuit.

Read more original source:
http://members.misty.com/don/igcoilhv.html

Ignition Coil High Voltage Generators

admin — Thu, 03 Jul 2008 07:41:20 +0000

Below is the schematic to a high voltage generator using one ignition coil. It runs fine on 6 volts, but you can change the 5 relay to a 9 or 12 volt relay, and run it on 12 volts. The average output (depends on the coil, the input voltage, etc…) is 40kV.

Read more original source:
http://www.geocities.com/mistertippy/schematics/ignition.html

Ignition coil as a generator

admin — Thu, 03 Jul 2008 02:27:55 +0000

My EHT3 project uses a solid-state oscillator and ignition coil to generate a very high a.c. voltage (using a spark gap as a guide suggests ~40kV). The project uses two d.c. supplies: one for the oscillator part and one to supply the power to the coil. This makes the circuit a bit more complex than most but prevents the ignition coil supply from upsetting the operation of the oscillator. Click on the circuit diagram below if you would like a detailed description of the design.

Read more original source:
http://www.hills2.u-net.com/electron/ignit.htm

High-voltage amplifier

admin — Thu, 03 Jul 2008 01:18:32 +0000

This Design Idea presents a simplified ac high-voltage amplifier that uses complementary, cascaded NMOS and PMOS transistors (Figure 1). The OP07 op amp has low input-offset voltage, low input-bias current, and high open-loop gain.

Read more original source:
http://www.edn.com/article/CA468423.html

Nitrogen Laser High Voltage Power Supply

admin — Wed, 02 Jul 2008 12:44:20 +0000

The schematic of the power supply is shown below. It runs off standard household power of 120VAC 50/60Hz, and the output is adjustable up to 25kV or more. For use with 50Hz power, the variable autotransformer shown in the parts list below must be attached to the power line at the ends of the coil, and not the tap as shown in the schematic.

Read more original source:
http://www.geocities.com/mistertippy/schematics/N2Laser.html

DC motor runs off of calculator solar cell in dim light

admin — Wed, 02 Jul 2008 06:38:29 +0000

How do we achive 10nA operation? By using diodes in place of pull up resistors, and by isolating the DC load from the trigger circuit via junction drops and the 10nF capacitor. If there is too much power comming from the solar cell then the motor might run too often or even continuously. You can avoid this by putting a 100K ohm resistor in series with the solar cell.

Read more original source:
http://members.shaw.ca/novotill/SolarPoweredMotor/index.htm

Simple light sensor adapter for oscilloscope

admin — Wed, 02 Jul 2008 02:13:07 +0000

This circuit is a simple visible light or IR detector for testing any equipment which outputs light. The circuit can be also used for measuring ambient light levels. This circuit is based on one photodiode which is used in photocell mode so that the photodiode generates a voltage and current signal when it get light.

Read more original source:
http://www.tkk.fi/Misc/Electronics/circuits/lightsensor.html

Solar garden lamp by CDS photocell control

admin — Tue, 01 Jul 2008 01:39:15 +0000

Reverse engineered circuit diagram of yet another commercially produced solar garden lamp. This one depends upon a CDS photocell to turn the light on at night, and although more complex than the circuits, it allows the battery to charge more efficiently.

Read more original source:
http://members.shaw.ca/novotill/SolarGardenLight/index.htm

Two LEDs perform rudimentary spectral analysis

admin — Tue, 01 Jul 2008 00:26:20 +0000

A pair of LEDs having different wavelengths can supply the stimulus for a rudimentary spectral analysis during quality-control sorting operations. By measuring the reflectance of each LED, the circuit in Fig 1 can provide information about the spectral response of the object under test. The circuit’s operation is akin to the human eye’s using three receptors to deduce information about the entire visible spectrum.

Read more original source:
http://www.edn.com/archives/1994/090194/18di4.htm