GPS-product RFI Problem Solving


If you want to understand troubleshooting the problem of RFI on your electronics, marine-radios and GPS-product then you have to understand the causes.

The average boat has several RFI noise sources often found on your gps-unit, gps-receiver, gps-navigation-system and radios-marine.

These noises are often classified as Radio Frequency Interference (RFI) or Electromagnetic Interference (EMI). They are am insidious enemy of communications and electronics systems.

It corrupts the GPS position fixes, makes a mess of your communications and generally causes electronics performance degradation. Solve


Essentially RFI is interference and noise that is superimposed as a disturbance or a voltage transient either on the equipment such as the radios or even the whole boat electrical power supply, or on the data and signal lines that carry your GPS or navigation data between each other. This noise is then processed along with all of the good data, which then corrupts or degrades the processed information. Solve noise and interference on your GPS-product, GPS-unit and save on radio-repair costs.


The voltage transient is probably the most damaging and has it’s source in many locations. Probably the best known effect is the corruption of your GPS and LORAN position data where the equipment power is taken off an engine starting battery.

What happens is that when a significant load is applied to the battery, such as starting the engine, a momentary voltage drop is created and what is often called a brown out condition occurs. This is then followed by a sharp voltage increase. This under-voltage disturbance can exceed 100 volts in some cases, which is very damaging to the equipment power supplies, and causes wiping of the memories or corruption of the data.

The same problem also applies to dual battery systems where the house bank supplies power to items such as the electric toilets and other large current equipment such as a windlass. The starting battery voltage can experience a 3 to 4 volt dip on a motor starting.

Transients are also caused by the variation or interruption of current in the equipment power conductor. Solve noise and interference on your GPS-unit, gps-receiver, gps-navigation-system, weather-radio and save on radio-repair costs.


The second common RFI noise source is called induced interference. Electrical fields are radiated from all cables and equipment. This can be induced into other closely located cables or equipment such as radios or GPS or depth sounder. The most common cause of this is where cables running parallel or within the same cable bundle, and this is also called mutual coupling.

Always make sure they are installed so that are laid so that power supply cables and data cables are kept separate and make any cable crossovers at 90º. Always install power cables to any sensitive equipment completely separate to the main power cables so as to reduce inductive and capacitive coupling to the data and signal conductors. Solve noise and interference on your  GPS-unit and save on radio-repair costs.

Part 2 of this 3 Part Series on RFI and Interference problem solving on your GPS and radios. Click on this link to find out more about. Part 2 RFI and all you need to know. GPS-product RFI Problem Solving Starts Here