SharkRF openSPOT3, Руководство пользователя

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AutoCal connector
AutoCal is a special connector - it does not connect to anywhere. It analyzes an incoming transmission from the
modem and tries to find out the frequency difference (RX offset) between the openSPOT3 and the transmitter.
openSPOT3's oscillator has a frequency stability of 0.5ppm, and every openSPOT3 is factory calibrated by us, so
you'll only need to use this special connector if your transceiver's transmit frequency is drifting. We suggest you
to only run AutoCal if the openSPOT3 shows BER above 1% for your radio's transmission, as errors in the voice
stream usually won't be noticeable if the BER is below 1%.
To use AutoCal, set the modem mode to the mode your radio uses and the modem frequency to the radio's
transmit frequency, then click on the
Save button. Hold the PTT button on your radio until all 3 phases are
completed. The found RX offset will be displayed at the Last found offset field and it will be automatically saved
for the current modem mode.
Keep in mind, that you can always check your own voice quality by using the openSPOT3's built-in local echo
service .
If the AutoCal does not enter Phase 2, then hold the PTT on your transceiver for at least the time it takes for the
progress bar to go from 0% to 100%. Make sure the transceiver is transmitting on the AutoCal frequency
(433.900 MHz by default). If the AutoCal still does not enter Phase 2, then the RX offset between the transceiver
and the openSPOT3 is greater than 500Hz. What you can do is to switch frequency on the transceiver or on the
openSPOT3, or enter an RX offset greater than 500Hz manually on the modem page and use the openSPOT3's
built-in
local echo service to find out the lowest BER.
AutoCal
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