LDA card records even if nothing is plugged into it

[Belinda Frick]

When doing extension side recordings, the card determines whether or not it
will record by the amount of voltage on the line. This means that when the
phone is on the hook there is more voltage running through the cable than
when it is picked up. As soon as there is a dip in the voltage, the card
will start to record.

Thus, if no cables are plugged in, the voltage is very low, and the
card will start recording. If you plug in cables that are not connected on
the other end, the voltage is also low and the card will start recording.
Only once there is a fair amount of voltage an the line, will the card stop
recording. If your cables are plugged in on both sides and the card is
still recording, you can use a voltage meter to check the voltage on the cables.