transmit a beep followed by a period of silence. The receiving beacon uses the strength
of the "beep-beep-beep" signal to locate the buried transceiver. The period
between the beeps should be silent.
However, most older analog beacons (e.g., the
Ortovox F1 and
F2) and some of the newer digital
beacons (e.g., the Ortovox X1
and early versions of the Ortovox
transmit a weak signal during what should be the "silent" period. This continuous
background tone is sometimes referred to as "continuous carrier." The red
line in the following picture illustrates this continuous background signal.
Of course, the receiving beacon always receives some ambient background "noise,"
but the continuous signal described here is actually transmitted by the transceiver.
You can test if a beacon is transmitting a continuous background signal as follows:
||Set the beacon in question to Transmit.
||Set an analog beacon to Search.
||Move the beacons two or three meters apart. You should hear
the beep-beep-beep of the transmitting beacon.
||Now move the beacons closer together. Listen for either silence
between the beeps (a good thing) or for a faint-but-continuous tone in the background
(a not-so-good thing).
The background signal is not a huge problem, but it can cause minor problems for
digital beacons which may interpret this as another beacon in the distance and may report "ghost"
beacons (i.e., report multiple burials when there is only one).
The Pieps DSP has a feature where it blinks
the little man icon ()
when it senses a background signal.