[Elecraft] Connecting Transceivers in Vehicles - Change ofRecommended Practice - OT

[Tom W8JI]

<<<New advice.
The new guidance is to connect the transceiver negative 
directly to the vehicle chassis and no fuse in the negative. 
(Assumes negative earth.) The positive lead should still be 
fused and connected to the battery or in accordance with the 
vehicle manufactures specific recommendation.
Remember that transceivers should be specified for vehicle 
use and the manufacturer’s guidance on RF power limits, 
antenna placement and DC supplies must be followed. Failure 
to do so might affect your insurance cover and questions on 
this point must be directed to your insurance provider.>>>

It's about time everyone had common sense about this.

If the device has a floating negative power supply buss, 
like the old Motorola land mobile radios designed for 
positive or negative supply vehicles, that ground loop is 
not present. Fusing the negative made some sense, or at 
least did not hurt.

Now a negative line fuse is a horrible idea. If you lose the 
negative path from the radio to the battery or from the 
battery to the engine block, it can cause all sorts of 
damage inside and outside the radio. We'll see how long it 
takes the rest of the world to pull its head out of the sand 
on this!

Tom