I've had my Krell KSA300S in storage for several years (climate controlled) and recently removed it to set it up in my house. The right channel didn't come up no lights, nothing. The left channel appears ok. No smoking gun either. So I started the journey to see what is going on.
First the visual check showed nothing obvious and no smell of a dead part. Capacitors look fine (haven't actually check them) but visually fine. To start with I check the voltage going to the output board and on the right side zero or a few millivolts. the left side wash according to the spec (73v).
So, I took the right side apart first thinking that the bridge rectifier could be at fault. Have yet to check it or the caps associated with it, because I did notice something weird. The 6 pin connector (there's 2) one of them had the middle 2 pins missing. Noting the fragile nature of the connectors I was careful separating the driver board from the output board. There were no pins anywhere and I'm very sure I didn't break the 2 since they would still be in the connector if I did. This unit worked fine before storage, so I'm trying to find out if those 2 middle pins were purposely eliminated at the factory. The photo shows the (upper portion of board the 6 pin connector with the 2 missing. The second attachment shows where I was measuring 0 volts.
Any help would be appreciated.
Thanks,
John
First the visual check showed nothing obvious and no smell of a dead part. Capacitors look fine (haven't actually check them) but visually fine. To start with I check the voltage going to the output board and on the right side zero or a few millivolts. the left side wash according to the spec (73v).
So, I took the right side apart first thinking that the bridge rectifier could be at fault. Have yet to check it or the caps associated with it, because I did notice something weird. The 6 pin connector (there's 2) one of them had the middle 2 pins missing. Noting the fragile nature of the connectors I was careful separating the driver board from the output board. There were no pins anywhere and I'm very sure I didn't break the 2 since they would still be in the connector if I did. This unit worked fine before storage, so I'm trying to find out if those 2 middle pins were purposely eliminated at the factory. The photo shows the (upper portion of board the 6 pin connector with the 2 missing. The second attachment shows where I was measuring 0 volts.
Any help would be appreciated.
Thanks,
John
Attachments
Those pins are hard and can only be cut deliberately with a cutter. Even if you bend them, you'll need to do it back and forth many times before they break. I do not see any heat related damage to it so its unlikely they fell out during soldering/desoldering too.
I would tend to agree but I don’t like seeing traces go to empty pins. I could check the other side but thought I see if anyone who had one noticed it to.
On a different note who knows the secret password for (separating) the heatsinks from the output board? All screw have been released and the enclosure plate moves freely but I can separate the board interface from the heatsinks. I don't want to apply force incase there's something else holding together. My first thought was they used heatsink compound and it's dried. The part associated with the blue line moves. The yellow highlight I need to remove.
John
John
