Hey Perry,
I powered the amp up and it is stable. So in theory I should have a clean audio signal going to the hip4080. Is this correct? I have added a pic of the pull down resistors I installed.
I powered the amp up and it is stable. So in theory I should have a clean audio signal going to the hip4080. Is this correct? I have added a pic of the pull down resistors I installed.
It appears that there is already a feedback resistor on the servo op-amp so I think you should have a clean signal.
Is the circuit the same? Pin 14 is where pin 9 gets it's input from. Pin 10 is only there for biasing.
I will have to trace it out in the morning but it looked similar maybe that ic3 I replaced isn’t actually a 2901N it was scratched off and I have all different versions of this come in to the shop.
This may be a bit too much to ask but if you have the amp open and on the bench, a set of level mapping of the signals on all of the op-amp outputs would be nice. If you do do it, set the input to get the output about 1/2 of the max (no load).
There is a daughter board that solders onto IC2 in this amp .
His pics doesn’t show that board in his amp .
Are you missing the board or did you remove it for trouble shooting ?
And I will post pics up later tonight or tomorrow for him .
His pics doesn’t show that board in his amp .
Are you missing the board or did you remove it for trouble shooting ?
And I will post pics up later tonight or tomorrow for him .
I have photos of 3 different versions and none show anything soldered to IC2. I'd be interested in seeing the board. If you're going to post more than 1 or 2 images, do so in a new thread and put a link that thread in this thread.
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That large capacitor 47uf 100v beside the speaker terminals. Someone replaced it on my board a epoxied it in and apparently it had exploded previously due to the capacitor packing in hard to reach places. Is that cap polarized or shave a negative marking or is non polarized?