Hi all.
Looking for some help regarding the workings of this unit.
Some time ago I picked up a digital bench power supply from the local flea market here in Rio. It's a 'Sincler SPS 3015/D' which I imagine is 30V, 1.5A 'Digital'.
Even though it would turn on and show a display, it wasn't working, and no matter how hard I have looked, I've found no reference let alone any kind of schematic. I imagine it is from the late 70's or early 80's? I can only assume that all the components are to the original specs although it had clearly had prior work done so it 'is' possible that some component is not to spec.
What keeps happening is that one or both of the 2N3055 transistors keep blowing, and I would love to know why?
Fortunately the main board is really quite basic. A dual voltage transformer, filter caps, rectifier diodes, two voltage regulators (7805/7905), a CA747 dual op-amp, two 2N3055's and various resistors and caps. Separate from that is the display control section.
Anyway, I no longer remember everything that was done, although for sure I changed the caps, and the two large 1Ω wire-wound resistors.
Does anyone have any thoughts as to what is going wrong here?
Adding a couple of photos I took shortly after getting the PSU.
Looking for some help regarding the workings of this unit.
Some time ago I picked up a digital bench power supply from the local flea market here in Rio. It's a 'Sincler SPS 3015/D' which I imagine is 30V, 1.5A 'Digital'.
Even though it would turn on and show a display, it wasn't working, and no matter how hard I have looked, I've found no reference let alone any kind of schematic. I imagine it is from the late 70's or early 80's? I can only assume that all the components are to the original specs although it had clearly had prior work done so it 'is' possible that some component is not to spec.
What keeps happening is that one or both of the 2N3055 transistors keep blowing, and I would love to know why?
Fortunately the main board is really quite basic. A dual voltage transformer, filter caps, rectifier diodes, two voltage regulators (7805/7905), a CA747 dual op-amp, two 2N3055's and various resistors and caps. Separate from that is the display control section.
Anyway, I no longer remember everything that was done, although for sure I changed the caps, and the two large 1Ω wire-wound resistors.
Does anyone have any thoughts as to what is going wrong here?
Adding a couple of photos I took shortly after getting the PSU.
Comment