F-2624 Review

There are voltage test points on the schematic. I removed the board, marked the test points with a sharpie, reinstalled and tested voltage very carefully.

Tape up the end of your probe so a slip won't cause a short

I'd check what voltages you're getting on 2624
 
Could not see any shorts with C16 or C17. Attached some images
 

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This is what astounds me about the people of AK. That someone would undertake a project like this and can depend on the members for assistance. I did the same thing many years ago with my Pioneer SA-9500II. All went well until the right channel would not let me adjust the DC offset. AK members sort of lost interest and I was frustrated beyond belief. I ordered all the parts to replace everything on both driver boards, but I never picked it back up.

I hope all goes well here as the 9090 is quite a fine piece of equipment and deserves to be restored.
 
The 38V "before and after the fuse" I presume to be 38VAC right? It needs to be spelled out.

There is no C17 on that board; I said and meant C16. It is probably one that you have replaced.

Your images in post #46 are of C704/705, the main filter capacitors.

Let's deal with D04 after you've looked at the above.
 
The 38V "before and after the fuse" I presume to be 38VAC right? It needs to be spelled out.

There is no C17 on that board; I said and meant C16. It is probably one that you have replaced.

Your images in post #46 are of C704/705, the main filter capacitors.

Let's deal with D04 after you've looked at the above.

Sorry my mistake. Yes the voltage was 38VAC
 
There is an empty soldered hole in pic 5 (just under the red wire) in post #21 in the area (I think) of the diodes D03/D04. What's missing there?
 
It's 9pm here and any minute now I'll be "nudged" to go for dinner. Take a really close look around diode D04 and other connections in the area.Something seems to be open around there.
 
Visual inspections does not show any issues.
 

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It's 9pm here and any minute now I'll be "nudged" to go for dinner. Take a really close look around diode D04 and other connections in the area.Something seems to be open around there.

The old C04 Cap had a third lead i believe to help hold stabilized due its size. The new cap is much smaller and only has two leads.
 
Visual inspections does not show any issues.
What is that white stuff around the base of C16 in the second picture of post #53 ?

Is it installed back to front? and 'vented' as a result? - might be fine actually - but this is the sort of stuff you need to be checking for. ;)
 
What you under C16 is some of the original glue used to hold the cap. C16 tested good, see image.
 

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OK so that's a cracked trace, bad joint or blown D04 all in that area. Heard the garage door open so now I really have to go for dinner. Check in later...
 
Here are the results of the diode testing.
 

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