Adding pre out to Onkyo HT R494

hello everyone, so I’m trying to mod my Onkyo receiver, and I would like to add some pre-outs to it

I have been looking at the service manual and if you look at the picture below, I think this is the preamp section where I should tap to get the pre-out.
This is the first time I’ve tried doing anything like this, and I would really like some tips.


thank you very much. Looking forward to start a discussion.
 
Better drop the image here...
But without the full schematics, it is difficult to say...
 

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Moderator
Joined 2011
Looks like if you change the Q4130 pin #5 connection from ground to instead Q4130 pin #3,
and then take the pre out signal from Q4130 pin #7, that will give you a buffered preamp output.

Use a series 10uF 35V NP coupling capacitor to each RCA pre out jack, if you like.
Note that IC packages are numbered counter-clockwise from the dot or notch, as viewed from the top.
 
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Moderator
Joined 2011
Ok, then use Q1700 (pin #7 for L, and pin #1 for R), and Q1702 pin #7 for C.

Add a 10uF 35V NP capacitor in series, from each of the above pins, to each RCA jack.
Be careful not to short the take off pins to anything else. Avoid loads under 10k each.
 
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