Notes on operation of the ICOM IC M802:
1.
It has been noted that the ICOM IC M802 does not like to send DSC messages in low power. For
some reason the Antenna tuner cannot tune and results in High reflected RF waves (SWR). This
results in improper transmission of the digital calling message. No similar problem has been
noted when the radio is set to medium or high power.
2.
Since there is no option to press the tune button when sending a DSC message. You should
always remain in Auto tuning as a result. If your radio continues to have problems tuning the
2177.0 KHz during a DSC message, try programming 2177.0 KHz in normal mode and press the
tune button before going to DSC. The tuner should be sitting where it needs to be for the
2177.0 KHz and may function better.
3.
All of the DSC calling frequencies are duplex except 2177.0KHz (“Ship”). That means that if you
were to try to call another vessel on other than 2177.0 KHz, on a duplex frequency, the other
shipboard radio is listening on a different frequency. If you need a longer range frequency than
2177.0KHz, you will have to program a higher frequency to be simplex on all radios you plan to
make DSC calls with. By inspection of the programmed DSC programmed Call frequencies you
will see that there are 25 international Call frequencies and one ship frequency
pre=programmed. The 802 is capable of only scanning 6 of those frequencies. Factory
programmed DSC Scanned Frequencies include:
T 2177.0
T 6312.5
T 12577.5
R 2177.0*
R 6331.5*
R 12657.0*
T 4208.o
T 8415.0
T 16805.0
R 4219.0*
R 8436.5*
R 16903.0*
* Scanned by receiver for calls. Ship to ship on Duplex frequencies will not hear the Transmitted
frequency except on 2177.0KHz.
I have re-programmed my M-802 for simplex channels 2177.0, 4208.0, 6312.5, 8415.0, 12577.5, and
16805.0 khz, for DSC Scan frequencies, and programmed "Call Frequencies", (both transmit and receive
frequencies for simplex channels). That means that when using DSC Watch Mode, I'm scanning those
frequencies listening for "Routine" DSC calls from other boaters on higher frequencies than the 2177.0.
This will extend the capability of using DSC calling various times of the day when 2177.0 will not reach
the other boats. The downside is unless other boaters re-program their radios, I will only receive ship
to ship calls on 2177.0 KHz.
ICOM IC – M802 Additions and Changes Planned for REV 2
Page 37 at end of section – If the channel being programmed is for receiving only (no transmitting
allowed) program the transmitter frequency as follows:
