[ScottRT]

No good deed goes unpunished. I built a C2 for a VA inmate because I knew it what what he was looking for to improve his lackluster sound.(He bought all the parts and did the chassis drilling, I'm not a complete saint)

I burned it in for 75 hours, mostly to form the Auricaps, and shipped it to him. 4 hours later it develops a noticeable hum, so I had him ship it back. It was only the left channel humming a clean tone, and I found that C207, a Nichicon that was supplied by Digikey, had started leaking both its innards, and AC voltage.

There are 5 of these 450v 47uf caps on the board. Should I replace all 5 of them in case its a 'bad batch' thing going on. I don't want the bloke to have any future issues.

Scott T.

[hagtech]

Was it in backwards?  You can try just replacing the one bad one.  Very uncommon what happend.

jh

[ScottRT]

No Jim, the cap was installed properly, polarity wise, and all the voltages were spot on... when I first fired it up and still now.

I will consider it a fluke and just replace the one. I have the same caps in my C2 I built 2 yrs ago with no issues.

Scott T.

[tubesforever]

Scott, the more I read your posts the more convinced I am that the Nichicons were perfect in your home.  If the cap that failed was cracked you would have heard it in your system.  Your equipment is top notch. 

I highly suspect the caps were frozen.  The customer fired it up before the caps were at room temp and this cause a fissure in the cap.  It was the first cap nearest the rectifier?  Am I right.  This cap and the rectifier are like a husband and a bride. 

I would just replace the failed piece and implore your customer to let it sit at room temp for a while before firing it up.   Let him know that these are chemical pieces.  If the chemistry fails then the capacitor fails. 

I think this was poor dumb luck.  If he had been out shopping and the box had come to room temp he would be singing Hagerman praises.  Actually I think there is a Gregorian Chant for Hagerman.  I just don't know Latin well enough to find one that describes "blessed sound of trumpets".

Happy New Year Scott!  Hope you are enjoying the playoffs.

[ScottRT]

Well, I replaced the bad cap and its nice and quiet now. It's on its way back to its owner, and i advised him to let it warm up before powering it up.

I would be enjoying the playoffs more if the Vikings had beaten Philly 2 weeks ago....

A great New Year to you too, Tubes....

Scott T.