HK 330B Question

[mikje]

I just picked up a Harman Kardon 330B receiver. It powers up, but no sound comes out. I checked the 2 speaker fuses and they are both open. Before I replace them, can anyone offer any advice as to what I ought to check, or does anyone know of an issue these old receivers had with blowing the speaker fuses?
Thanks.
Mike

[lineup]

hello
I should search diyaudio.com for 330B
http://www.google.com/search?q=+site:diyaudio.com+330b

found this interesting post

Originally posted by Algar_emi
Harman-Kardon 330B schematic needed

I just found in the garbage (incredible what people are putting to garbage) a nice Harman-Kardon 330B.
I just put the 2 speaker fuses in, then the amp works just fine.
The tuner seems ok too. It has a discrete phono stage, separate bass/treble adjustement for left and right, AM-FM, aux input (for CD) and even a preamp output. It is all discrete amp and tuner.
I would like to have the service manual or just the schematic in case it breaks down.
I'll give it to one of my boys for Christmas.
Thanks in advance.

In the same topic you can download Service Manual. From Harman-Kardon
http://manuals.harman.com/hk/Service...K330b%20sm.pdf

Why does speaker fuses blow in one amplifier output?

If one is blown, we can guess a shortcut of the output terminals, in that channel.
If both are blown, we may look for the answer in the amplifier.
Depeding on the amplifier this can be several causes.
- DC offset on output
- Oscillation on output
... and a number of other things

What we know, is that it takes high current to blow one fuse.
To blow two fuses, it takes two high currents