ASA Electronics MS-306 T E C H N I C A L B U L L E T I N

T E C H N I C A L B U L L E T I N

This bulletin will discuss DC Power sources and

how they relate to 12 volt DC video products.

A large number of our products are designed for

12 volt DC applications. The power is supplied by

a variety of sources i.e., the battery, converters,

ignition systems and solar power.

Our general specification for the voltage range of

operation is 10 to 16 volts DC. TV’s and VCP’s

(video cassette players) require slightly more than

10 volts to function properly. Normally this 10.5 to

11 voltage requirement does not create a problem,

but keep in mind the following points:

The voltage of a fully charged battery (engine not

running) is approximately 12.5 VDC. Once a load

(items being powered represent the “load”) is

applied, the voltage will drop. How much the

voltage is reduced will depend on the following:

1. Current draw (amount of amperage); the

higher the draw the greater the voltage

will drop.

2. This size and length of the conductor

(wire) supplying power.

A TV will draw considerably more amperage than

a VCP. For instance, a 14” TV will draw

approximately 3.5 amps compared to a VCP that

draws 1 amp while the tape is being loaded or

ejected. Checking the voltage of a TV while it is

playing shows an approximate 1 volt drop, (11.5

VDC). The voltage at the VCP can be another

.5VDC (11 VDC) less than the TV.