LOPT / FBT Tester
This little instrument identifies faults in horizontal output stages by doing a `ring` test, i.e. it applies pulses to the LOPT / FBT primary circuit, and counts the number of damped oscillations or `rings` produced. For each `ring` down to about 15% of the test pulse amplitude, one LED in the `bargraph` lights up... nearly all faults will greatly reduce the number of `rings` and give a very low reading. visit page.
It can be used on both monitors and TVs because it`s not frequency-sensitive, and the test signal amplitude is only 650mV- low enough not to forward-bias semiconductors in the circuit. To do a basic test, you connect the test leads between chassis