Shack Power Connectors
The simple matter of connecting amateur radio equipment to power is becoming increasingly difficult with the wide variety of connectors in use today. It seems that every different manufacture of amateur equipment has to come up with another type of power connector. Even from one model to the next for some brands of equipment, changing of power connector seems to be mandatory.
Keeping these factors in mind, a few amateurs in South Australia when on the hunt for a cheep readily available power connector that could be used as a standard for 12 volt DC power systems.

The solution that was finally settled on could not do everything, however most applications were catered for. A combination of two pin and four pin connectors manufactured by Utilux or Molex formed the solution.
· 2 pin connectors for loads upto 12 Amps
· 4 pin connectors for loads upto 18 Amps
The paralleling of the positive pins and the negative pins allows the four pin connectors to carry up to 18 amps continuously.

The two pin connectors have two halfs, Plug (Utilux 1545P or Molex 03-09-2021) and a socket (Utilux 1545R or Molex 03-09-1027).

 

 

The four pin connectors also have two halfs, Plug (Utilux 1490P or Molex 03-09-2041) and a socket (Utilux 1490R or Molex 03-091041).

All you have to remember is the point of the connector is positive. Otherwise just keep this sheet handy and you can’t go wrong.

The Plug has two male pins (Utilux 1190 or Molex 02-09-2103) and the Socket has two female pins (Utilux 1189 or Molex 02-09-1104).
The four pin connectors used the same pins, just double the amount in each connector. Also the two positive pins are connected in parallel together and the two negative pins are connected in parallel together. This is to increase the current handling.

What items use which connectors? The Socket half (either 2 pin or 4 pin) is used for the power source, for example a battery or a mains power supply. The Plug half (either 2 pin or 4 pin) is connected to the appliance, for example, a radio, TNC, GPS, laptop, DF equipment and etc. An example of this is shown in the following diagram.
Where do you use a four pin connector in stead of a two pin. The way in which you decide is based on how much current the appliance draws at 12 volts when operational. If the unit consumes less than 12 amps, then a two pin connector will do the job. If the appliance draws more than 12 amps but less than 18 amps, then a 4 pin connector is to be used. On the other hand if the appliance draws more than 18 amps on a continuous basis, a different connector that the two mentioned above is required.
For larger applications the Anderson SB50 is a good connector for up to 50 amps, and if even more current is required, then Anderson have a good range of connectors to suit your requirements. However, the price of the Anderson connectors prohibits their general use by amateurs. If you have a high current power supply, you can’t go past a couple of Anderson connectors to connect the power supply to the shack bus bar system. Some amateurs have even mounted a couple of SB50 connectors in the car connected to the car battery and backup battery for use during field days. This seems to work very well, as you make a lead that has one SB50 connector to several 2 pin and 4 pin Utilux sockets. No problems finding enough power sockets to plug all the contesting radio equipment into.

 

 

 

 

 

 

 

 

 

 

 

 

Page updated on 9 May 2008