SM7A repair..

So I bought a broken SM7A.  No output.  Usually these things break at the cable, but this one seemed to have no output from the capsule.  It was obvious that someone had been inside of it messing around..

But anyway, I did some troubleshooting and figured out that it was indeed the capsule that was dead.  Being that I paid money for this, and there are no exact replacement parts for the SM7A (they do sell SM7B assemblies, but for more than I paid for this..) I decided to see what I could to do fix it.

First would be to trace through the wiring as far up as I could..  I carefully peeled back the tape covering the super thin wire from the diaphragm itself..  And found wire with some kind of corrosion.. Probably years of humid breath..

I ohmed the wires and found it completely open..

Now, the only option would be to try to get to the diaphragm's coil and see if it was open.

I carefully peeled the edges of the diaphragm up, which wasn't hard because the glue was so old and dry..  I then ohmed out the wires directly at the coil..  And found that the coil was OK, but there was a rotten section between the coil and where the wire goes through the body.

My only choice was to connect new wire to the old wire so I could extend it back down through the body:

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Next, I cleaned off the face of the backplate and cleaned out the flux gap:

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And finally I threaded the wires back through, and glued the capsule back onto the plate:

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I measured AC voltage when blowing on the capsule, and I saw no rubbing through the microscope, so I suspect it's fixed.  I'll have to test the sound and see what it's like.  The new wires were a little bit thicker, so hopefully they don't add too much weight to the diaphragm.