When a digital beacon is turned on, it performs a self test.
If an error is encountered, most transceivers will either display
an error number on the screen, change the color of an indicator
light, or blink an indicator light.
The Pieps DSPs (and maybe
some other transceivers) uses a tiny fourth antenna to transmit
a weak signal during the self test. This allows it to test that
the other three antennas can receive a signal. However, if you
turn it on when close to a transmitting beacon or an electrical
device, the DSP may report an error during the self-test
because it is receiving an unexpected signal. People sometimes misinterpret
this as a problem with the transceiver when in fact, it is indicative
of a thorough self-test. To avoid these phantom errors, you should
be at least 5 meters from any electrical devices or transmitting
beacons when you turn on your Pieps DSP.
S1 and the
also have power-on self tests that test the transmitting signal.
perform self tests every five minutes to check the battery strength,
the transmitting frequency, the transmitting power, etc. If a problem
is detected the ARVAs will emit three long beeps every five minutes.
S1 and the Mammut
have "partner" or "group check" modes that check
your partner's transceiver. These mode typically require your partner's
transceiver to get within about one meter of the transceiver before
receiving a signal. The S1's manual states that during this
test is it is checking the frequency, "transmission period,"
and "period length."