Have also used the following with success:
When working on connecting your radios, etc. with wires and a shielding braid, look at "Solder Sleeves". These are used to attached a ground wire to the shielding braid of a shielded cable.
Solder sleeves can also be used to connect wire to wire.
Basically a clear plastic "butt connector" with three rings in a clear tubing. Put the wires (or the shielding braid) in and apply heat. Center ring is solder, melting and making a soldered joint. Colored ring on each end seals. Tube shrinks for a great connection.
Google Solder Sleeves. Cleevet Technology Incorporated (Google) carries a great collection and even as kits with assorted connectors.
Woody