Hello everyone

I’ve found this circuit on YouTube channel for electronics
Need discuss it with you, that it really can test the uc3845,3842,3843?, these series?
With only vcc input?
Please give your experience regarding this circuit as I’m willing to make one for test this ic as I’ve met a lot in repair work and had doubts that it’s faulty, so such a circuit can be a solution
Regards

 

Looks good to me, though I'd use 100nF decooupling on pins 6 and 7.

 

What is the device claimed to do in the line of testing?? I was not able to access whatever was posted.
Knowing what the test is supposed to consist of is very useful towards determining towards seeing if a test circuit can be useful.

 

It allows the voltage on Vfb to be adjusted, and it produces as sawtooth ramp of variable amplitude on CS.
So the output pulsewidth can be observed (it needs a 'scope) as the amplitude of the signal on CS is varied and as the voltage on FB is varied.
A voltmeter could be used to check that the reference voltage is OK.
And that's about all that a 3842 does!