Emim repair, close but no cigar!

I had a couple of emim's go out on my RS 4.5's the other night, swapped a pair out of my RS 2.5's so I still have tunes, thankfully.

So today reread the emit repair thread and decided tonight I'd screw up my courage and at least try to see what was the problem. One measured 68Ω's and the other 45Ω's so I had a feeling they weren't toast since I still had some resistance.

There are six screws that hold them together that use a cap type of nut with a shallow phillips head. I loosened them before I made a crude fixture out of a 2x10. I took the four screws on the sides completely out. Them grabbed some 16 penny nails and nailed the emim with contacts down to the board leaving about 1.5" roughly above the emim. Cut the nail heads off with a bolt cutter. Which gave me enough room to slide the emim up enough to get the last two screws out. I carefully lifed the top section off enough to see that there are two more brass screws that bolt into the board that holds the mylar in place and makes contact via a wire to the external leads see picture.

Lifting up enough to get the 1/4" brass nuts off the front came off with out problem. I cleaned up the bolts and nuts with brasso (took about an hour). Put the assembly back together which was a PITA to get the tiny nuts back on. I took a measurement a crossed the screws before I put it back together and got 3.4Ω's but once I put it back together it read 7.6Ω's Better but not good enough, should have removed the brass nuts that hold the external leads on and cleaned them I guess...

When I get another chance I'll tear it back down and go and find new nuts and bolts and try again. Corrosion is definitely the enemy...

I had more pictures but the camera was low on batteries so this is the only one that I got. More later...
Cheers
Army

Cool. I'll certainly stay tuned.

Those sure are tiny buggers. I'd almost need some of those old-man glasses if I were any older.

cabinover said:

Those sure are tiny buggers. I'd almost need some of those old-man glasses if I were any older.

Click to expand...

Laugh while you can Bob, you'll need those old man glasses just like me before long assholio

Between the sweat of trying to pull a part an emim that is delicate, expensive to replace and these old eye's and shakie hands of mine, not too mention the roaring thunderstorm outside... not to break my hand patting myself on the back, I thought I was doing pretty good

I know brother, you don't have to tell me. I'm slowly getting so where I have to pull things away from my eyes to see them. Sad.

Hell, it didnt work anyways. Good call trying to repair it. I am sure you will be much better at it the second time.

Evan

I had to upgrade to a 19" monitor so I could see the print on the screen

Army, there are still solder connections there at the ends of the short wires. Maybe a quick hit with the solder gun will rejuvenate those solder joints (like on the Emits). Would be nice to see more pics of the Emim. I can't envision the connection to the diaphragm.

Sounds like you are on the right track though with the progress made so far :thmbsp:

Army,
Brave you are. I am staying tuned. Thank goodness for the baby brothers.

Vito

I updated this thread so we don't clutter up the forum with too many stickies :thmbsp:

Top shelf old man! Top shelf.

Your nail-fixture is an exercise in working simplicity. I'll be using it for my next Emit repair :thmbsp:

My EMIMs have light surface rust in the magnet crevices between the mylar and the front of the assembly. Tempted to take them apart to clean. Funny how the EMITs have no rust on the screws or magnets. Army, I love the jig and will copy it for the job if I go for it.