Are they all 2SC458 transistors bad? It seems that there are at least 2 different case styles. Are the 'newer' ones that were made, say in the 80's, also bad?
I have a JVC A/V receiver that uses a few of these in the video circuits. I have my satellite receiver hooked through this and once in a while when I turn everything on - TV, receiver, satellite, the picture is screwy. The picture is like when they used to have pay TV in the 80's- scrambled, colors all screwy. Turning off the receiver and turning it back on will straighten it right out. This is usually accompanied by at least one of the three fuse lamps not coming on. So I guess this could also be a power supply problem. I haven't measured any voltages, other than at the plug that goes to the fuse lamps. It is very close to the -24V that it is supposed to have. Of course that was measured when it wasn't acting up. BTW, the 3 (8V, 200mA) fuse lamps are in series. Each lamp has an 8V zener diode parallel to it. I guess this is so that if one burns out the other 2 remain lit? Anyway, I was just wondering about those transistors. Thanks for reading.
I have a JVC A/V receiver that uses a few of these in the video circuits. I have my satellite receiver hooked through this and once in a while when I turn everything on - TV, receiver, satellite, the picture is screwy. The picture is like when they used to have pay TV in the 80's- scrambled, colors all screwy. Turning off the receiver and turning it back on will straighten it right out. This is usually accompanied by at least one of the three fuse lamps not coming on. So I guess this could also be a power supply problem. I haven't measured any voltages, other than at the plug that goes to the fuse lamps. It is very close to the -24V that it is supposed to have. Of course that was measured when it wasn't acting up. BTW, the 3 (8V, 200mA) fuse lamps are in series. Each lamp has an 8V zener diode parallel to it. I guess this is so that if one burns out the other 2 remain lit? Anyway, I was just wondering about those transistors. Thanks for reading.
