CDI System
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Elektronik Design LABoratoriet
CDI - Capacitor Discharge Ignition:

The Tesla HV supply TBU12V25KHZ with the CDI400 is a Capacitor Discharge Ignition system ready to be used for petrol engines or other purposes where a heavy spark is needed.

CDI400 has been developed with modern fast switching circuits to increase rate of change. Considerable design effort has been put into obtaining the best result. Special attention to high frequency technique and components has enhanced the spark properties and thus its energy without increasing consumed energy.
It is possible that such a better spark may utilize energy derived from quantum fluctuations. This is the only explanation we have for the enhanced efficiency.

Maximum spark frequency is 200 Hz.
Signal input is 8 to 20 V, 20 mA.

The TBU12V25KHz with CDI400:
Weight is 380 grams (0.38 kg).
Size is 125 * 88 * 70 mm.

Connect this unit to any standard engine ignition coil and obtain 20 KV to 30 KV sparks.
The high rate of change, achieved with CDI400, generates hefty sparks which emanates flaming plasma clouds and micro ball lightning. This is an area we would like discuss. If you have any knowledge of these phenomena please send e-mail to Gunnar  .

A Little CDI History:
In 1967 a CDI ignition equipment was designed. (See the '1967 CDI' diagramThe '1967 CDI' diagramto evaluate
this early design).
To the surprise of the engineer, the released sparks were enormous. A standard ignition spark
could hardly ignite silk paper, let alone thick cardboard, but the CDI supply not only ignited
2 mm thick cardboard in a flash, but made veritable flames shoot out from the spark plug.

Kavazaki 90cc with CDI system

The result from this CDI fitted on a 90cc Kawasaki (pictured above) was very encouraging. In those
days CDI ignition was, by many, considered worthless and dangerous. Today most vehicles are
fitted with some kind of electronic ignition.