A little background - I own a 2012 Dodge Charger Pursuit that I am turning into my mobile ham station. It already has most of what I need, but I ran into something I want to ask a question about.

It has wiring provided to the center console area for accessories. This includes 3 20a always-on and 3 20a accessory circuits. It also has a dedicated ground wire.

Does it make more sense to do my own power distribution to the trunk and mount the transceiver there? I don't mind running extensions for mic and control unit (I'm thinking of the icom id-4100a), or does it make more sense to run the antenna cable from the trunk to the center console and wire the radio in there?

I'm on the fence, so I want to see what you all think :-)

  • 2
    $\begingroup$ The bible of mobile installations can be found here: http://www.k0bg.com/ $\endgroup$ Feb 5 '18 at 13:43
  • $\begingroup$ I believe your question is open for interpretation and opinion. Hence a factual answer is probably not feasible. The place where to mount your radio is a personal choice based on your vehicle, and perfernces. How to mount, and bond, and wire, what to do, what not to do, can all be found in the link I posted in another comment. $\endgroup$ Feb 5 '18 at 13:46
  • $\begingroup$ @EdwinvanMierlo - Thanks for the link! I've never done a mobile radio install before :-) I'll definitely spend some time reading through that site! $\endgroup$
    – Ozzy S
    Feb 6 '18 at 12:13

The ID-4100A draws 13 amps on high power (50W). The voltage rating specified in the manual is 13.8 V DC ±15%; therefore, the minimum voltage at the transceiver is 11.73 volts. Many transceivers will not transmit if the voltage drops to that level. Therefore, if you run DC all the way to the trunk, you'll need to use fairly large conductors to minimize the voltage drop.

The instruction manual suggests mounting it under the passenger seat, and the detachable console below the dash. The power leads could be smaller located there. Ohm's Law and a chart showing resistance per foot are your friends. You have to calculate the drop in both the + and - leads, and don't forget that there is additional voltage drop across fuses, connectors, and the console wiring.

  • $\begingroup$ I did some thinking around resistance and voltage drop, but didn't even think about voltage drop across fuses and such. I also forgot to calculate resistance on the ground cable. This car has some funky wiring IMO. From the battery in the back, there is a 6awg 125a fused line to an accessory fuse panel 2-3 feet from the console. Between the console and that box, the wires are listed as 16awg (they look more like 18..). I'll do a more thought out voltage drop calculation now. Is there an assumed/known value for things like fuses and connections? $\endgroup$
    – Ozzy S
    Feb 6 '18 at 12:24
  • $\begingroup$ @OzzyS "...the battery in the back"? $\endgroup$
    – Mike Waters
    Feb 6 '18 at 12:59
  • $\begingroup$ Yeah... I had the same thought when I first bought the car. It's kind of growing on me though. $\endgroup$
    – Ozzy S
    Feb 10 '18 at 7:02
  • $\begingroup$ @OzzyS Is the battery in the trunk? Behind the rear seat? $\endgroup$
    – Mike Waters
    Feb 16 '18 at 5:14

You're better off spending time routing power for the radio and future accessories. Spending time now adding in relays and fuse blocks will make adding things easier. Later on you might want to add in a second radio, 6m or HF. Go bigger on the wire, it's cheaper to plan ahead then redo it later.

I'd recommend running new wire from the battery instead of tapping off of the 6Ga wire. Blowing a fuse for your radio's isn't a big deal, losing half the car if the main blew isn't near as fun. Size your fuse's rationally. Keep it looking clean and you'll thank your self later.

Furthermore those signal wires have more issues with voltage drop, smaller wire has way more resistance. It's generally more advisable to extend power vs signals.


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