SONAR

1. SONAR what it is

2. SONAR usage general

3. Which parts compose it

4. Basic features - Capabilities

5.  Choosing the one according to our needs

6. GAIN basic principles

7. FREQUENCIES (50 KHz - 200 KHz ) basic principles

GPS

1. GPS what it is

2. GPS usage general

3. Which parts compose it

4. Basic features - Capabilities

5. WPT (waypoint)

6. ROUTES

7. CHARTS

8. Choosing the one according to our needs