- Joined
- May 14, 2014
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- 2,280
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- Southwest Kootenays BC
- Tagline
- No such things as bad days, just bad moments
If anyone likes to tinker with old junk like me, don't believe the data sheets. They show a pin configuration of ECB but that is not correct. At least it isn't for early squarish 2SC548 with the beveled top. Those are actually BCE. It seems that when they changed the shape from square to round the pin arrangement changed as well to ECB.
This has just now confounded me while fixing an Akai CR-83D with a bad noise problem. Having learned through an Akai GX4000 of the existence and reputation of 2SC458's, I figured it likely there were some in the CR-83D and there were - four of them.
I put in replacements with the same pin configuration as per the data sheet but there was no sound of any kind afterwards. I scoured forum threads and found one from 2009 on AK which explained this discrepancy. The GX4000 had fourteen of those things and I did replace them all but I can't remember reversing them. Maybe i did and just forgot in the intervening time - memory is the first to go they say.
In any case after reversing the transistors i just put in, the CR-83D plays fine now.
2SC458's were supposed to have been used by many Japanese manufactures in the 1970's not just Akai - Marantz, Sansui, Pioneer, Kenwood etc. I just thought it worth mentioning the irrelevancy of the datasheet in case anyone runs into this same dilemma.
This has just now confounded me while fixing an Akai CR-83D with a bad noise problem. Having learned through an Akai GX4000 of the existence and reputation of 2SC458's, I figured it likely there were some in the CR-83D and there were - four of them.
I put in replacements with the same pin configuration as per the data sheet but there was no sound of any kind afterwards. I scoured forum threads and found one from 2009 on AK which explained this discrepancy. The GX4000 had fourteen of those things and I did replace them all but I can't remember reversing them. Maybe i did and just forgot in the intervening time - memory is the first to go they say.
In any case after reversing the transistors i just put in, the CR-83D plays fine now.
2SC458's were supposed to have been used by many Japanese manufactures in the 1970's not just Akai - Marantz, Sansui, Pioneer, Kenwood etc. I just thought it worth mentioning the irrelevancy of the datasheet in case anyone runs into this same dilemma.