So I was rebuilding my Nikko Alpha-1 amplifier...and tracked down to a bad power transistor an NEC 2SB600...
The Japanese who built this unit in the 70's were very meticulous and of course there are a LOT of obsolete parts...
When they show the power amp boards in the schematic they kind of cheat the actual build by putting all the positive transistors on the left channel and all the negative transistors on the right channel...due to my own lack of "take a damn picture before you take it apart" I has to take apart the entire left channel (wherein is the failure) and what they ACTUALLY did was sandwich the transistors both negative and positive on each side, so that there are 3 power transistors per side, both +/-...on each side with wiring harnesses connecting the sides...(you have to pay attention because on the schematic it shows both types of transistors PER side, but only LABELS them as one type...obvious typo...ie: the left side ONLY labels the transistors as SB600's when in truth both SB600 and SD555's exist per side.
So now obviously have to track down in the actual schematic how they are wired because I removed all of them on one side to test and left the wiring harness hanging...with no pictures of how to put it back.
Here's my rant...
Why in the hell is there not a standard numbering naming nomenclature for parts?
In my limited approach it would seem wise to make NEGATIVE power transistors numbered with ODD numbers and positive transistors numbered with EVEN numbers...just makes sense right?
And I'm sure the industry has moved a bit towards this in the last 50 years, but still...
On the schematic the negative power transistors are numbered Q4/6/8/10/12/14
The positive power transistors are Q3/5/7/9/11/13
Just freaking dumb...kinda like me not taking a picture of the harness before I disassembled it.
The Japanese who built this unit in the 70's were very meticulous and of course there are a LOT of obsolete parts...
When they show the power amp boards in the schematic they kind of cheat the actual build by putting all the positive transistors on the left channel and all the negative transistors on the right channel...due to my own lack of "take a damn picture before you take it apart" I has to take apart the entire left channel (wherein is the failure) and what they ACTUALLY did was sandwich the transistors both negative and positive on each side, so that there are 3 power transistors per side, both +/-...on each side with wiring harnesses connecting the sides...(you have to pay attention because on the schematic it shows both types of transistors PER side, but only LABELS them as one type...obvious typo...ie: the left side ONLY labels the transistors as SB600's when in truth both SB600 and SD555's exist per side.
So now obviously have to track down in the actual schematic how they are wired because I removed all of them on one side to test and left the wiring harness hanging...with no pictures of how to put it back.
Here's my rant...
Why in the hell is there not a standard numbering naming nomenclature for parts?
In my limited approach it would seem wise to make NEGATIVE power transistors numbered with ODD numbers and positive transistors numbered with EVEN numbers...just makes sense right?
And I'm sure the industry has moved a bit towards this in the last 50 years, but still...
On the schematic the negative power transistors are numbered Q4/6/8/10/12/14
The positive power transistors are Q3/5/7/9/11/13
Just freaking dumb...kinda like me not taking a picture of the harness before I disassembled it.
