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kexodusc
07-09-2004, 06:29 AM
I bought a NAD 3300 Power Envelope (what's that?) integrated amp yesterday for $10 bucks. The unit will not switch off completely. When depressing the power switch, the amplifier part disengages (kills the sound output) but the LED's remain lit and I can still hear a slight electric hum.
Anybody have any ideas what might be the root of this evil? Faulty switch? Relay?

I have a few extra swiches around I could pop into it.

The thing works great, except for the fact it is perpetually on, requiring me to use a wall switch or unplug the unit.

Any help appreciated.

skeptic
07-09-2004, 06:37 AM
Here's a wild stab. Look for a small pc board mounted relay. Within the last year I've had an electric wall over and a television set fail because of one of these cheapo relays (both were the same brand relay.) It may just be jammed and need replacement.

kexodusc
07-09-2004, 07:11 AM
Here's a wild stab. Look for a small pc board mounted relay. Within the last year I've had an electric wall over and a television set fail because of one of these cheapo relays (both were the same brand relay.) It may just be jammed and need replacement.
Yeah, I wasn't holding my breath on the switch. Since I have some I'll replace it anyway...just curious, do you recall the brand of relay?
Where did you find a replacement?

skeptic
07-09-2004, 10:19 AM
I haven't replaced them. I called GE to repair the wall oven. They sent several different replacement boards which were wrong and then the closest thing they had to a right one. Then they sent a technician to install it. He was on the phone to his boss and his office on and off for an hour and was also on his laptop as well most of the time before he got it right. In the new and improved design, they had eliminated the relay that failed altogether because it was totally unnecessary. The technician was highly competent but his instructions that came with the board weren't. Functions of some of the other wires in the harnassing had changed. All this took almost a month. The relay was probably worth about $2. Cost of repairs $248. The Sony TV which failed popped a 1.6 amp fuse in the power supply. It looks to me like the relay failed and took the fuse with it but I really haven't checked it out yet.

kexodusc
07-09-2004, 10:24 AM
Thanks for the info.

Just curious, have you ever painted the chassis of an amplifier before? This thing has a few scratches, but it's got a billion sticker remains left behind that I can't get off...I'm thinking of sanding it down and refinishing it in a nice metallic black.
Never painted anything metal before, any suggestions?
By the way, I just realized I'll have more fun with this thing for less than the price of a movie. Cool.