Tune your antenna before your first transmission after selecting a new frequency band.
If your rig has a tune button use it, don't depend on the auto tune function. Depending on auto tune can cause the first part of your transmission to be low or missing (also known as clipping.) For example, when transmitting, "Southern Sails" only "ails" is sometimes heard. It is okay to have the auto tune function enabled in case you forget to use the tune button.
Select high power especially when checking in on a net. Don't assume that the receiving station has good conditions on their end.
Exceptions: When using your rig for email, select the lowest power that will work. SailMail and Winlink will usually work on low power (~20 watt.) Also if you know that propagation is good to the receiving station, select a lower power. Selecting a lower power will save battery, extend your radio's life, and is less likely to interfere with receiving stations.
Marine radios are set to minimize background noise like wind or engines. If using a Ham rig, make sure that settings for mic gain and ALC (Automatic Level Control) are set appropriately.
Make sure DC power at the radio is good and batteries are charged.
Interference can be caused by a number of things on your own boat such as Danfoss refrigerators, NMEA data, florescent lights, computers, pump for the freezer, GTO cable near the solar panel control, etc.
Verify voltage is good to radio during transmit. Should be less than 1 volt drop between battery and radio power terminals.
Turn off any high current equipment that can cause interference on the power supply to the radio.
Inverters and battery chargers are typical sources of noise.
Have a good ground plane.
Copper foil is much better than wire due to "skin effect."
Query: How to change power output settings for Icom 706?
Rick: I recommend reading the manual for your radio.
Location of the microphone to mouth. Marine microphone recommends speaking directly into the mic, assuming wind. (Le Bella)
Speak sideways into the mic to avoid air puffs. (St Jude)
Use low power if in close proximity. (Salty Paws)
Shore power ground increases reception interference. Better to D/C shore power. (Destiny)
Tune by whistle on low power. Use RF power button on Icom 707 to decrease power. (Le Bella)
Change to FM mode instead of whistling. CW or FSK work too. (Salty Paws)
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