Hi Max ... so happy I found you. I was reading here at this old posting about Johnson Fitness power board and I need some help if you can.
Link : https://forum.allaboutcircuits.com/...ol-board-johnson-fitness-jdyf02l-revg.110355/
At first I thought my UC3842 was cooked ... it has a very odd crater like mark on it but removed and built test circuit and is fine ... bought a new one anyway. What I found next is Q6 (beside Q7) is cooked ... so would you happen to know what those part numbers are ? Closest I can see on the smd marking (A6 for Q7) is it's a N chan mosfet ... but who knows. The marking on Q6 is completely gone and Q7 has BBH and A6 on it. It was described in that post that these two Q6 and Q7 are a set of push pull transistors ... I also removed Q7 to test it and it doesn't read like a mosfet should ... could use yer help there master.
Journey11
Link : https://forum.allaboutcircuits.com/...ol-board-johnson-fitness-jdyf02l-revg.110355/
At first I thought my UC3842 was cooked ... it has a very odd crater like mark on it but removed and built test circuit and is fine ... bought a new one anyway. What I found next is Q6 (beside Q7) is cooked ... so would you happen to know what those part numbers are ? Closest I can see on the smd marking (A6 for Q7) is it's a N chan mosfet ... but who knows. The marking on Q6 is completely gone and Q7 has BBH and A6 on it. It was described in that post that these two Q6 and Q7 are a set of push pull transistors ... I also removed Q7 to test it and it doesn't read like a mosfet should ... could use yer help there master.
Journey11