







1. Complete Battery Lighting and Communications Package |
2. Basic 2-Wire Trailer Plug Connectors as purchased in the store. The wires are simply cut in the center when building the system. For DC Power systems (includes all battery systems), The BLACK is NEGATIVE! In this photo, the BATTERY PLUG is on the LEFT. EQUIPMENT PLUG is on RIGHT. |
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11. Radio Equpment with plug. Voltage should be clearly marked on all sensitive equipment. 12 Volts. |
12. Cig Lighter adapter cord. Note clearly marked plugs. The "charge battery only" plug should be insulated with tape when not in use. 12 Volts. |
13. Battery Clip 9 Volt adapter. |
14. Gel Cell Rechargeable Battery. This one is two 6 Volt batteries in series, making 12 Volts. A fuse connects between the two cells. |
15. Battery Substitute/Plug for a Compaq Laptop Computer. Old NiMH batteries have been removed, a small hole is bored in the side of the pack, and the wires are soldered in place. |
16. Extension Cord. Several of these are handy for all equipment, especially headlamps.. This one is 4 feet long. Use lamp "zip" cord or cable. Suggest 16 guage or larger to prevent voltage drop. |
17. GPS Receiver with Plug. 6 Volts. |
18. Portable Computer with Battery Substitute/Plug. The Ni-Cad batteries are removed from an old worn-out pack. A plug is then wired into the pack by soldering. 6 Volts. |
19. Cave Radio Transceiver (185kHz SSB/CW) with Plug. 12 Volts. Antenna Not Shown. |
20. Battery Substitute/Plug for ICOM Handheld Transceiver. The Ni-Cad batteries were removed from a worn out pack, and plug wires are soldered in place. 6 to 12 Volts. |
| Connecting Equipment to Plugs
. To connect plug wires permanently to electronic or lighting equipment, select a plug which has the black wire to the insulated side of the plug. Then simply strip about an inch of insulation off the end of each wire, twist the appropriate wires together, and secure with electrical tape. This connector lends itself to field repairs and also connecting just about anything by simply inserting wires into its openings and taping them in place. For plugs such as those used on transceivers and other electronic equipment, the trailer plug wires are soldered directly to the appropriate type of plug. See example in photo 7. |
Durability and Strain Relief
. The Simple 2-Wire Trailer Connector has been used for many years in the automotive industry and is extremely durable---even cave-proof. Still, care should be taken not to pull on the wires when the connectors are being un-plugged, especially the first few times the plugs are inserted and removed, until they start to loosen up a little.When in use, especially for headlamps and battery packs carried in rough environments, it helps to use tape to secure the cord on each end so that there is not a direct pull on the plug wires at where they enter the connector. |
Spool of Field Phone Wire with Plugs Attached. Courtesy of Walt Pirie. |
This application for field telephone wiring was submitted
by Walt Pirie. It is a spool of surplus comm wire, as frequently used in
cave rescue applications, with a handle.
Walt writes:"Another useful application of these connectors. The VPI Cave Club uses them on its field phones for cave rescue. There's one attached to the phones. One is wired at at each end of every spool, and a spare one taped below it. The spare one has bare wires on the other end. That way it can be plugged into the attached one leaving the bare wires for attaching to wires from other groups that don't have the connectors.---Walt " |
| Author's note:
Careful checking of polarity when building this might help it to be used as a long extension cord in the field. Although, some voltage drop will be encountered, depending upon how much load is used. Field Telephones are capable of producing over 100Volts AC when the ringers are used. Don't plug your GPS into this :-) ---Bonnie |