DIY Class A/B Amp The "Wolverine" build thread

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#2,943
mainframe99 said:
Heres right channel 5W into 8R as installed final in chassis with lid on - the left channel looks distortion identical but there is slightly more 50hz mains noise due to the RCA input wiring running around the whole perimeter of the chassis.
Click to expand...

Maybe time for something like this? 🤔

PXL_20230926_173914386.jpg
 
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#2,944
Unfortunately, the boards don't have mirror symmetry anywhere. That's because the output transistors have a particular mechanical relationship to the heatsinks. Everything but the output transistors can be handled without changing the layout, although that would break the thermal coupling of the 6 IPS transistors. Just mount everything on the bottom instead of the top, being careful to turn the transistors and heat sinks appropriately. You'd end up with the CCS transistors tops on the heat sink rather than the proper bottom, but that would not matter much as there is little need for that heatsink anyway.

Then the only mandatory layout change is to swap the emitter and base of the output transistors. That does not look like it would be too difficult. Rotate the emitter and base resistors on the axis in the board plane located at the collector and parallel to the short board dimension. That should result in a layout that is nearly topologically equivalent to the current layout.
 
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#2,945
I should have mentioned it doesn't bother me - I could just rotate one board on the heatsink to get both IPS at the back of the chassis, like most builders here have done, but I liked the look of the outputs on top. Thats the penalty, about 5db more 50hz noise - I still can't hear it and don't care. To be fair its inside a chassis with the lid on so what does it matter how it looks inside lol
 
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#2,956
I don't think the 100v caps will fit that board though. At least not the high uf ones. I saw the example psu in pdf format, is their a bom or gerber to go along with it? Or more of an explanation of recommend parts/values? I kind of get the gist of it, but I'm no electrical engineer so it's not very helpful to me. If there's a good way to to fit large caps to diya store psu, that info would work as well. Or just point me to a thread with a psu that will work. I've been searching for a while now and have not found much info for anything above 60v, and only sus ebay units.
 
#2,958
MilkyChance said:
I don't think the 100v caps will fit that board though. At least not the high uf ones. I saw the example psu in pdf format, is their a bom or gerber to go along with it? Or more of an explanation of recommend parts/values? I kind of get the gist of it, but I'm no electrical engineer so it's not very helpful to me. If there's a good way to to fit large caps to diya store psu, that info would work as well. Or just point me to a thread with a psu that will work. I've been searching for a while now and have not found much info for anything above 60v, and only sus ebay units.
Click to expand...
I had this problem in the past too (if I think we’re talking about the same thing) where all the 10kuf 100v caps are 40mm dia, nothing exists in 35mm afaik, so why oh why are all the PSU rectifier boards all 35mm caps?
 
#2,959
deerhunt said:
I measured rail amps and got 29-32mA in positive and 32-35mA in negative.

The tip regarding diodes being affected by the short on Q106 made me do some measuring on D112/D114.
They have no forward voltage !! Resistance measurment shows 2 and 13 ohm!
On the other side D111/D113 appears functional, shows 0,55-0,6V.

So next step is to replace D112/D114. Fingers crossed nothing else is blown...
Click to expand...
How you get on mate, any joy?
 
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