donbosco: Dom Bosco Mosquito Injector

ID: 468600
donbosco: Dom Bosco Mosquito Injector 
27.May.18 14:32

David Sanderson (GB)
Articles: 4
Count of Thanks: 3

My example was not functioning and I decided to dismantle the probe to understand its function and design.

The dismantle process can only be done in a destructive manner but yielded useful information as follows:

The device is essentially composed of a non blocking oscillator comprising only a pulse transformer with two windings, a PNP transistor (2N408) and a capacitor of value around 500pf.  The precise value was not readable as the capacitor appears to have been damaged (probably by connection to a high voltage equipment under test).

The circuit appears very similar to the Eico injector of a similar vintage (details on


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