Resistor values (no schematic available)

Identifying that chip may prove to be difficult!
I currently can’t see any marking under the dried adhesive

IMG_6758.png
 
That is not good news Andy - are you sure there are no markings on the side of the can, clearly there is nothing on the top. Lets hope the IC is still OK.
I’ve carefully scraped some of the dried adhesive off and still can’t see anything , I think I’ll have to remove it to get a closer look.
The components surrounding it do have black smoke like marks on them 😩
 
That schematic does not show any details on the PSU, however it does show a +/- 15VDC supply for the op amp. So my guess is the PSU IC is a dual +/- 15 volt DC regulator in a 10 pin metal can IC.

The ones in the photo in post #20 are 68 ohm. Do the burnt ones measure open circuit?
 
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I am guessing that the IC is an LM325H dual tracking +/- DC voltage regulator, interesting that the resistors are still measuring OK, so they are seeing heavy current. The IC is overload and current limit protected, so maybe faulty tantalums - that would not be the first time.

If the IC is faulty, it is obsolete so apart from a China copy, I do not know where you might get an original TI or NS device.
 
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