I'm sorry you've had trouble.
'ICOM M-802 Radio Manual for Idi-Yachts' book.
Not my favorite reference. Marti doesn't always communicate facts clearly.
On page 16 of the book there is a diagram that shows that you should NOT connect the green wire from the transceiver to the tuner. The Tuner should be connected via copper strap to a groundplane.
Unless you installed an isolator ( T-4
) in the coax between the radio and the tuner there is already an RF ground between the two: the coax shield. Unfortunately there is also a ground connection through the tuner control cable. Adding a ground-to-ground wire between the radio and the tuner increases the potential for a ground loop.
1. Am I correct to say the KISS groundplane is NOT the same as the tuner groundplane?
The KISS is a counterpoise and not strictly speaking a ground. In some cases you can get away without one or the other but a proper installation will work better.
Connect the KISS to the ground stud on the tuner and route it as far from other conductors on the boat as you can. If you have to cross another connector, cross at a right angle.
Run a ground, preferably copper strap to a ground point. A Dynaplate is great. Alternatively, drill and tap a small hole in the foot of a bronze through hull and connect to that. Don't count on the engine or tanks as a true ground. Engines "ground" through the shaft and there are rotating connections that aren't very efficient. Tanks are not grounded.
2. Is the engine mount a suitable tuner groundplane as we have a fiberglass sailboat with plastic/pvc tanks?
No. See above.
3. The local SSB tech advised me that damage may have been done to the transceiver if the tuner was not properly grounded - is this correct?
No. The radio has what is called "foldback circuitry" that automatically reduces the output power of the radio to protect itself. It's pretty hard to mess it up.