Sanken CU-41 Repair

[monteallums]

I have a Sanken CU-41 I purchased in the mid 80s. For 40 years it was a real workhorse until it wasn't. It became extremely noisy and lost volume. I had a good idea what the issue was. My search for a scheme led me here. Thank you to all the forum members that posted info on the Mic. It was invaluable in helping me do the repair. As I originally thought, the electrolytic caps were bad. They did last almost 40 years so I ain't complaining. The biggest hurdle was figuring out how to open it up. Which I finally accomplished using a rubber mallet and a small screwdriver. I have posted some pics that hopefully might help someone here in the future.

 

[jonas bonnetta]

Thanks for sharing. I have one on the way out and need to get it opened up. Can you tell me how you were able to open it with a screwdriver and mallet? Thanks in advance and happy new year!

 

[RuudNL]

Just in case you need a schematic: this is what I have.
In the one that I repaired the problem was a defective capacitor in the (potted) impedance converter.

 

[monteallums]

Thanks for sharing. I have one on the way out and need to get it opened up. Can you tell me how you were able to open it with a screwdriver and mallet? Thanks in advance and happy new year!

I used a small miniature screwdriver with a rubber mallet placed in one of the small divots. Just remember lefty loosey. Mine wasn't screwed in tight so it was easy to remove. Be careful though. Once the bottom is removed the entire microphone will fall apart. Just make sure it's on a flat surface. To fix mine all I had to do was replace the four 10uF Electrolytic capacitors. Size is important so make sure you get the correct replacement type. They are bipolar BTW. I just used some Nichicon 50V. Good luck..

 

[jonas bonnetta]

Thanks guys!!!
Happy new year!