help fixing sony De-875 amp

pepsicolla · Joined: 14 Oct 2007 Posts: 4

Hi everyone. Im new to this site and very happy it exists...read some posts and seems as though theres some very smart people on here.
the story:
A friend of mine stayed over my house and hooked up his ipod to my amplifier via the headphone jack and turned the amp on "phono" he fell asleep and the next day the speaker outputs no longer worked. (i was told using the Ipos in conjunction with phono was a big no no but i wouldnt know).
I have since checked for speaker output voltage on the main board (10 pin connector on mother board) and still no voltage.
I have found some schematics on this site which are helpful but give me no resistor values an so on.
I did read someone have a similar problem and a response was to "resoder the speaker protection relays" but i have no idea where to find something like that.
The Amp seems to function in every other way and the earphone jack does still work. If anyone has any other information that would be greatly appreciated.
schematics, ideas, some more detailed direction....anything
thank you in advance
joe.
feel free to call if theres some information that could be hard to explain.
518-368-7150

pepsicolla · Joined: 14 Oct 2007 Posts: 4

anyone?

vtech · Joined: 08 May 2006 Posts: 1264 Location: USA

Can not follow your description? Are you saying that ipod was hooked up to your sony via headphone jack? and amp was set to "phono"?.

While It is correct that "phono" setting should only be used for phono and nothing else, it is simply an RCA input located on the back of the unit---- it absolutely has nothing to do with "headphone" jack located on the front panel, whatsoever!

Now, I do remember that some of the Sony's with 1/4 inch headphone jack on the front panel utilized a switching mechanism inside the jack to shutt off main speakers when you'd insert a headphone which could malfunction---not sure if that's the case here?

pepsicolla · Joined: 14 Oct 2007 Posts: 4

The ipod was hooked up to the amp through the headphone jack (with adapter) on the front of the amp. I was not there (until later) but i was told that the amp was set to the phono selection.
A male to male headphone jack was used from the ipod to the amp. So basically the the jack on the amp (being an output) was being used as an input. I have no idea how but music was produced. In the end the ipod won.
It was left on overnite and all 5 audio outputs arent producing anything. Im pretty sure the sub is still working.

pepsicolla · Joined: 14 Oct 2007 Posts: 4

Im being told the amp was turned up quite high to produce moderate levels of music.