| ak_47_boy |
I have an oscilloscope with a bad switching power supply. I have it out of the scope and set up with the correct dummy loads for testing. I see no visible burnt components or capacitor leakage. The switching transistor gets very hot, i would say about 80C (180F). It should output:
+12, +12, -12, -5.2, +3.5, +5.2
I measure:
+12, +12, -2.6, -2.6, +3.5, +5.2
Old electrolytic caps? Bad regulator? It is a double sided board and quite compact so i am having a lot of trouble following traces. I think i am going to start desoldering and testing all the components individually. |
|
|
| Eva |
| Find the diode that feds the negative rails, it may be the same for both, being the -5.2V one derived through a linear regulator. Check that it's not shorted. |
|
|
| ak_47_boy |
| Tested all diodes and rectifiers. They are all good. Could they only be failing to work at high frequency? |
|
|
| star882 |
| Looks like an overload. Check components on negative rails for partial shorts. |
|
|
|
