Hi all.
I have try to develop an inventer according to the following schematic...
When it was switched ON (I used automatic fuse switch 50 A) after 6 seconds the automatic switch was turned OFF by itself and heatsinks on 2N3055 transistors were a little warm and no output voltage at the secondary winding of transformer. 8O
I started to check parts and execution of schematic, and:
1. The frequency is about 50Hz on pins 10 and 11 of 4047, OK;
2. Also this frequency was after resistors 4.7K goes to LM358 inputs, OK;
3. Let say on pins 3 and 5 of LM358 this frequency also present, OK;
4. But then no frequency outgoes on pins 1 an 7 of LM358! I think it is not good, as far as I can understand the circuit the LM358 is in voltage follower mode and the frequensy has to be also present on output pins 1 and 7. But it doesn't, only voltage is about 0.6V present at bases of 2SC1061.
5. Furthermore no any works after LM358 outputs... Probably can be possible to add an series 10K resistors to pins 3 and 5 of LM358 connected to power supply and ground accordingly, to do some biasing of input signal. Or I am wrong and here should be other serious solutions...
Please can anybody help me to fix my problem with this inverter? Thank you in advance.
P.S. How can I check if the rest of transistors (2SC1061 and 2N3055) are OK and didn't damaged? So, how to check it in PCB by digital multimeter without desoldering of those parts?