Hi, I've noticed there are A LOT of threads on the topic already. I have used the search function but I have some questions in addition to those already asked/discussed, so please bear with me!
The PSU board is Indigo 600109.
q401 and q402 are both broken (IRF740) - this part is readily available. As this seem to be a common problem, why not put in a tougher component? Any suggestions? (I buy components at Farnell if possible. Otherwise ELFA or RS)
Apart from these and a couple capacitors starting to gain a bit of ESR, the board seems to be ok.
The board next to it (with the power amplifier transistors on it) is simply labeled Indigo (c) 2002. Again a few bad capacitors as expected, but here's the puzzle:
One transistor Q100 is labeled 108 C930AB. My first guess is sanyo 2sc930 - but the 2SC930 is ancient and discontinued long ago, and the marking on the casing does not resemble what I find if I google the part. Also according to the datasheet, the gain is marked by C, D, E or F. Nothing on the AB suffix. Pins 1+2 are shorted so the part has to go (unless it's not a transistor at all, and meant to behave this way 😕), so what do I replace it with?
The PSU board is Indigo 600109.
q401 and q402 are both broken (IRF740) - this part is readily available. As this seem to be a common problem, why not put in a tougher component? Any suggestions? (I buy components at Farnell if possible. Otherwise ELFA or RS)
Apart from these and a couple capacitors starting to gain a bit of ESR, the board seems to be ok.
The board next to it (with the power amplifier transistors on it) is simply labeled Indigo (c) 2002. Again a few bad capacitors as expected, but here's the puzzle:
One transistor Q100 is labeled 108 C930AB. My first guess is sanyo 2sc930 - but the 2SC930 is ancient and discontinued long ago, and the marking on the casing does not resemble what I find if I google the part. Also according to the datasheet, the gain is marked by C, D, E or F. Nothing on the AB suffix. Pins 1+2 are shorted so the part has to go (unless it's not a transistor at all, and meant to behave this way 😕), so what do I replace it with?
I'm happy to report some progress:
I put the C930AB into my LCR meter and it says it is an N-channel JFET. Strangely the LCR meter recognizes the part even though pin 1 and 2 (Drain-Source) seems shorted.
I also discovered that the FSB SS5i have almost the exact same boards, and the service manual is available in one of the older threads on this forum. I'd already downloaded the file (among a whole bunch of other Indigo SMs and schems), but had overlooked how extremely similar the boards are.
The board hosting the C930AB is very similar, but some components differ (possibly a different revision of the same board). The C930AB is replaced by a J113. Also an N-channel JFET, and readily available - so I orderd one of those as a possible replacement.
I put the C930AB into my LCR meter and it says it is an N-channel JFET. Strangely the LCR meter recognizes the part even though pin 1 and 2 (Drain-Source) seems shorted.
I also discovered that the FSB SS5i have almost the exact same boards, and the service manual is available in one of the older threads on this forum. I'd already downloaded the file (among a whole bunch of other Indigo SMs and schems), but had overlooked how extremely similar the boards are.
The board hosting the C930AB is very similar, but some components differ (possibly a different revision of the same board). The C930AB is replaced by a J113. Also an N-channel JFET, and readily available - so I orderd one of those as a possible replacement.