There are two capacitors bulged(10uf and 220uf), 120 and 2.2ohm resistors, show a weir value also.
That transitor is completely shorted. The other one next to it it's fine.
Is that tested out of circuit or in? The caps are in parallel IIRC. I have no access to a service manual right now but I will try and get one.
Nothing happens.
I have tried uTorrent too and it can't parse the link.
That link it's complete?
Back to the receiver, it works!!!!
How to adjust the bias?
There are two pin test points, close to the final transistors and each channel has an adjustable resistor, on the pre amp board.
I believe, that these receivers fail with this error, because some final transistor are not tightened properly. I mean, I could tighten a half a turn on some screws.
Anybody has a good source of 0.22 ohm/5W dual resistor?
I have only 3W one.
You can measure the Voltage drop on the 0.22 Ohm Emitter resistor which will represent the current draw through the power transistor.
Do you know what the bias current should be? Just multiply the 0.22 Ohm with the bias current to get the voltage drop on the resistor.
I.E. 50mA bias current = 0.22 x 50mA = 11mV.
Then I have no idea what those two pins are connected to and if they are for bias adjustment or not, but you do have have another channels that have the same 0.22 Ohms resistors for the power amp section, you can take the voltage reading and see what you get compared to the one channel that you just repaired, typical bias current for the output transistor is between 30~60mA range, it is set to give minimum crossover distortion but too much bias will cause transistor to get hot, such as the one with Class A amplifier.
It may not apply here but some of these Onkyo Receivers can be repaired no charge under Onkyo's Special Service Program http://www.onkyousa.com/Support/ Check your model/serial to see if it qualifies.
08/19/2014 Loss of Audio/Network Connection Customer Care Program
This one, it was in protect mode, so it doesn't apply.
In my opinion this type of defect should be included as well in a recall.
To me, it seems like some final transistors are not properly tightened down and they eventually will fail.
Across the two test points, (white plastic base with two pins sticking up) Onkyo specification calls for 9mv per FL FR and C channels and 6mv across all others.
As I said, I haven't got the service manual to hand to prove it but that is the correct specification.
Cut off an old fan connector and glue it to the end of a biro pen, run the wires out of the other end and splice them into some banana plugs for your meter. Nice, cheap adapter!
At 0.006V yes that's fine - Sorry I've just scrolled up and read the rest of your posts since.
On these 626s, often replacing the 0.22 ohm resistor will lead to a monstrously high quiescent current on that one channel as it usually takes out some of the resistor network I mentioned previously. Keep an adapter on it as you power it on and be prepared to pull the plug if it starts to ramp.
I will try and get you the proper information for the above for before your 0.22 replacements arrive. I'm no longer working for the Onkyo warranty centre so don't have immediate access to the service manuals (if I'd seen this a week ago there'd have been no problem..!)
I don't know anything about that quiescent current, or what to do about it.
I'm not an expert.
I have already turned it on with a 3W resistor and it's working.
The pre-amp section, seems quite hot.
I have transferred the fan's plug to the empty one, to run constantly. I have done it, on my other 616 also.
Quiescent current = the 6mV reading you took from the test points..! (before anyone jumps in and says the current can't be taken in mV and that it doesn't make sense; this is word for word from the service manual!)
The Pre-Amp section does run hot, mind, but you shouldn't be able to feel anything more than mild warmth if you put your hand on the top of the heatsink. Worth running through and checking each channel is in spec after 6-8 minutes of power-on time (no inputs or outputs connected).
Comment