Started tidying up my mobile install.

[KD2GOE]

any tips or tricks are welcome
I am not an expert in a radio installed in to a car but this is what i have so far.
1 thing i am going to do is relocate the negative connection to the body of the car and add more grounding straps to the trunk lid i have 1 right now.
SWR is good and low on my 15,20&40 meter MFJ Hamtennas. all dip to 1.5:1 and up to 2:1 to the usable parts of the band that i have privileges on. any any tweaking is down with the tuner. i am going to add a home made remove switch to switch from the mag-mount to the stud mount so i don't have to play with connectors. i did add an audio cap manly because i had it laying around. also when i was parked i would see my lights dim a little and it helped.
i also have a 40 amp fuse at the battery and 10AWG wire to the radio.
has any one use random wire as a antenna counterpoise i was thinking of adding 2 wires to lay out when i am parked to help with adding a counterpoise?

special thanks to Camaro1 for the Alinco SR8 it is rocking!

 

[Mudfoot]

What's the story on the encoder knob?

 

[KD2GOE]

What's the story on the encoder knob?

lol
The stock one is heavy and there is no drag so when driving and hitting bumps in the road the freq moves a little. I put that one on so the freq wont move when i am driving. one other option i was playing with is adding felt to the back of the stock knob.

 

[n8fgb]

40 amp fuse is to big. Run both power leads right from the battery, and fuse both.
Rich

 

[fourstringburn]

Run both power leads right from the battery, and fuse both.
Rich

Second that.

You should always provide a direct return ground path back to the source, the battery. Chassis grounding can lead to ground loops when used for 12 volt power grounding and could play havoc on modern vehicles ECM's.

Negative connections have voltage on them too so this line should be fused as well.

Fuses should be 25 to 50 % of the load draw from the radio being used. Typically a 100 watt HF draws around 20 amps, so a 40 amp fuse is fine.

 

[KD2GOE]

40 amp fuse is to big. Run both power leads right from the battery, and fuse both.
Rich

That is just the fuse protecting the 10awg wire at the battery just in case the wire is comprised. there is 2 other fuses at the radio that are 25 amps

Second that.

You should always provide a direct return ground path back to the source, the battery. Chassis grounding can lead to ground loops when used for 12 volt power grounding and could play havoc on modern vehicles ECM's.

Negative connections have voltage on them too so this line should be fused as well.

I have been told that you need to run the negative to the frame of the car
and i have always done this with "audio equipment". when i did a few car stereo installs i did a negative to the battery and that made a bad ground loop, then installed it to the frame and never problem..

The Negative connection to the radio is fused but what about the coax to the stud mount that is in contact with the frame of the car? so that would in turn negate any fuse on the Negative connection. right?

 

[KD2GOE]

The way i was thinking of the negative fuse, was for some one running an AMP. If that amp lost its ground some how, the fuse on the negative wire of transceiver would pop not allowing current to flow down the coax in-search of a ground.

 

[fourstringburn]

I never heard of a ground loop from a direct battery connection. By definition, a ground loop is a voltage differential between 2 different points to a ground connection.

For the people who say to use the chassis for 12 volt DC grounding, ask specifically why that is so other than that's the way is has always been done.

Chassis grounding for 12 volt electronics is old the school way of thinking. While yes it works, but it can cause ground loops which I have experienced with radio /amplifier setups before.

Your stud mount /coax shield creates a D.C.bond and a RF ground as well if mounted properly like you did to your vehicle. This allows RF currents to travel back to their source.

As I said before, your negative lead still has voltage so that's why your radio's power cable has a fuse on it.

 

[KD2GOE]

I understand what you saying.

I think i need to add this if you do run the negative lead to the battery and have a D.C.bond from the radio through the Coax to the car body. You NEED a fuse on your negative lead to the battery. If your verticals stock battery to frame negative lead or engine ground strap fails for any reason your wire running from your battery to the radio to the coax stud mount will become the only way current can flow to electrical system of your vehicle this this will cause a FIRE!
i have seen this first hand to many times when people ran "beats" in there car..

In my car there is 1 wire to the frame and one running to the engine block T'ed off the battery post.