OK, thanks for the pic. It seems the location of any solder bridge in lieu of the jumper wires is not obvious, so I have no idea what the author of the procedure was describing.
However, you measured only a few mV across the resistor when a specified 25-35mV should have been read, which I think means there is a bridge across the test points, apart from the 1R resistor or the jumper wire. It should be easy to measure across the TPs for continuity (low resistance) when the 1R resistor was removed. It would read open circuit if there really is no other jumper. Otherwise as I said, that small resistor would have burned up when speakers were connected and used.
Note; if you try to set 25-35mV with a short in place when only the resistors should be used for testing, there will be serious overheating and damage. Test by measuring the voltage again with and without the resistor (just hold it across the TPs) to compare. If the voltage doesn't change much, the resistance is obviously much less than 1R before you even fit it.
Unfortunately, this is not really finding the culprit flagging a protection fault.
However, you measured only a few mV across the resistor when a specified 25-35mV should have been read, which I think means there is a bridge across the test points, apart from the 1R resistor or the jumper wire. It should be easy to measure across the TPs for continuity (low resistance) when the 1R resistor was removed. It would read open circuit if there really is no other jumper. Otherwise as I said, that small resistor would have burned up when speakers were connected and used.
Note; if you try to set 25-35mV with a short in place when only the resistors should be used for testing, there will be serious overheating and damage. Test by measuring the voltage again with and without the resistor (just hold it across the TPs) to compare. If the voltage doesn't change much, the resistance is obviously much less than 1R before you even fit it.
Unfortunately, this is not really finding the culprit flagging a protection fault.
I was comming to the same conclusion about the jumper/solder link issue it just didn't make sense.
I removed the jumper I had installed & the 1ohm resisitor and measured across the TP's and still had continuity. I then disconnected the blue flying lead which is going from TP11 to earth and remeasured. No continuity across TP11 & TP4
I put back the 1 ohm resistor, (it still measures 1.5 ohm in or out of circuit) and I get continuity.
Pwered up measured across the TP's reading 25.1mv turned it off.
I removed the jumper I had installed & the 1ohm resisitor and measured across the TP's and still had continuity. I then disconnected the blue flying lead which is going from TP11 to earth and remeasured. No continuity across TP11 & TP4
I put back the 1 ohm resistor, (it still measures 1.5 ohm in or out of circuit) and I get continuity.
Pwered up measured across the TP's reading 25.1mv turned it off.
Well, I imagine that's what was meant by "solder link". This must have been a manufacturing mod. to avoid fitting the jumper wire but it's not a smart term to use since all links, jumpers etc. are soldered. Anyway, you have found it, bias is OK and that's good as trying to set bias without locating and removing the link could be a disaster.
I've had a closer look at voltages in the protection sensing circuit and I'm doubtful about a few voltages. For a another clue, could you check D203,204 voltages - to either side from ground and also simply across it. From what I can see, both channel protection circuits interact and I'm not sure how TBH. I would appreciate any suggestions or comments from others to make this process a little quicker, too.
I've had a closer look at voltages in the protection sensing circuit and I'm doubtful about a few voltages. For a another clue, could you check D203,204 voltages - to either side from ground and also simply across it. From what I can see, both channel protection circuits interact and I'm not sure how TBH. I would appreciate any suggestions or comments from others to make this process a little quicker, too.
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