Lrl from Italy

[Inna]

Originally Posted by omar

The bc547c / bc548c / bc549c transistors have a gain in the lower limits of 420hfe.
The circuit needs to adjust and reduce the value of the resistance R12 to achieve the required gain with it. As our friend Franco said.

Note it has a wider bandwidth than the bc183c

I'm sorry Omar, but the 548C has hfe gain from 420 to 800, the ones I selected for my circuit, I tested them with a Chinese multi-tester and they all have hfe values ​​above 500. Do you think it's too low? Better if I replace them or by intervening on the resistors, can I still get a good result?