Icom IC-M802 Installing page 19

Optimizing SSB Receive
rick medero 2015
Settings on your rig:
1. Turn squelch off. I have not found a squelch that works well with HF SSB. It can get to be tiresome listening
to static but that is the nature of SSB.
2. Set RF gain to max (see your rig's operators manual).
3. Clarify to zero (see your rig's operators manual).
4. If using Ham rig, turn OFF AF based filtering ( DSP noise reduction), experiment with options for controlling
AGC response time.
Interference:
Local interference frequently comes for electronics on your boat, boats nearby and land based electrical
equipment. Observe the bars on your display during receive, when no station is transiting. Also listen to the
static. Ideally less that 2 bars should show and the static should sound like static (no pattern to the noise). If this
is not the condition turn off electrical devises on you boat to see if any are the source of the interference. Note
that many devises can still interfere when they are off but still have power supplied, so it is best to turn breakers
or switches off that are supplying the power. Refrigerators, solar panel charge controllers, AC charges and
inverters are among the worst offenders, but can be most anything from LED or CF lights, to watermaker
controls. I help one boat where it was the watermaker even when it was off, we had to remove the 12v supply to
get the interference to stop. In this case it did sound like normal static but about 5 bars showed the interference.
Equipment or installation issues:
I have seen a few cases now where tuners have relays that become resistive and cause receive to be low while
transmit seems ok. What happens is the higher voltage when transmitting arcs the contacts resulting in lower
resistance. This usually shows up just after tuning were the receiver is quiet until you transmit, then RX is fine,
but can intermittently go resistive again. Sometimes tapping on the turner will cause it to go quiet or get better,
this is one way to determine if issue is in the tuner.
Resistive antenna connection. Similar to tuner relay problem above, but connection between antenna and tuner
or tuner and radio.
See hints on antenna and counterpoise.