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Constructing the Adapter for the Sennheiser ME 3:

For the hard core among you, we gladly provide you with the following instructions for constructing the adapter yourself and some good source of needed supplies. Remember, if this is too much for you, about $12 will get one shipped to your door. Here goes:

Needed parts:

1. Locking 3.5 mm jack (Calrad part # 30-297) - best price $3.24 plus shipping
2. Audio cable with 3.5 mm jack on either one end or both
3. Rosen core solder
4. Soldering gun or pencil
5. Black electrical tape
6. A few tools including needle-nosed pliers, wire strippers, and fine wire cutters. A multi-tester is also useful.

Sources for above parts:

The key threaded 3.5 mm audio jack: You can't buy the jack or audio cable directly from the Calrad, but there are numerous suppliers throughout the US. The best price appears to be from a company named Wallco Industrial Electronics. Wallco charges $3.24 for the jack. The specific part can be found here. Additonal sources of this jack include Electronics Parts Direct and Minute Man Electronics.

Audio Cable: Although you can purchase cable, an isolated 3.5 mm audio plug and solder these together, the price of a cable with attached jack is so little, that it makes sense to purchase an audio cable with attached audio plug. A audio cable with a standard male 1/8 inch or 3.5 mm audio plug on one end can be purchased at any Radio Shack or even more inexpensively from Walco or another industrial supplier. If you plan to make more than one, it's more cost effective to purchase a cord with male plugs on both end and cut it in half, using each end to construct an adapter. The Calrad part numbers for these double male end cords are:

• 55-897-2 (2 ft. length)
• 55-897-3 (3 ft. length)
• 55-897-4 (4 ft. length)
• 55-897-6 (6 ft. length)

Each cost under $2 from Walco, which is about half of what you'll pay at Radio Shack. If you need soldering supplies or some of the recommended tools, I would suggest your local Radio Shack.

The process: (Pictures to be added soon)

1. Strip off about 3/4 inch of the outer insulation from the jack cable
2. Identify and isolate the outer shielding wire, separating it from the other two insulated wires
3. Strip the insulation off of all but the last 1/4 inch from the two colored wires. This should be done with a wire stripper appropriate for the size of the wire. Be careful not to cut into the individual strands of these colored wires as this may create "stray" wires which can cause trouble later.
4. Cut the wire about 1/8 to 3/16 inch from the end of the insulation.
5. After neatly twisting the individual strands of the wires from both the shielding and two colored wires, melt a small amount of solder onto the tips of each wire in order to anchor the strands to each other.
6. Identify (using a multi tester or other device) which of the colored wires attaches to the most distal tip of the male jack. This will be attached to the tab indicated in the diagram. The other colored wire will be attached to the other tab as indicated. The shielding or ground wire will attach to the extended portion of the female jack.
7. Key: insert the jack cover over the entire cable for later assembly.
8. Begin assembly by inserting the ground cable through the appropriate hole in the jack. Don't solder it yet.
9. After bending each of the colored wire about 90 degrees just at the end of the insulation, carefully insert these into the holes in the appropriate aspects of the jack and further bend them over in order to keep them in place.
10. Carefully solder each of the colored wires in place
11. Solder the ground wire in place
12. Carefully cut off any excess wire extending beyond the solder
13. Carefully inspect all connections and be sure there are no stray wire strands
14. Cover the exposed wire with vinyl electrical tape (you'll want to trim the tape and not use it a full width
15. Slide the jack cover in place
16. Test your new jack to assure proper operation
17. You're done!

Need some instructions in soldering? Here are two online tutorials:

• Tutorial on how to solder
• Another Soldering Tutorial