doofoo

Hi All,

I am taking a long trip coming up and want to throw a ham radio in my car. However, I am having a hard time finding a power source & ground. I would love to just run directly to the battery and tap in there, but I can't seem to find a gromit that I can pass a 8 or 10guage wire through the firewall. They all seem to be out of reach.

So I ask of you all, where would I tap into for power and where would you ground?

2003 C32. The radio draws 20amp at full power, so I need a pretty large power source as to not overload the wiring in the car, tapping off someone for a light or something

Thanks,
Mike

Capt Nemo o2

If you take off the fuse panel cover in the car and under the hood there is plenty of room to pass through the firewall... Just follow the wires in there!

doofoo

The fuse panel under the hood is on the drivers side, correct?

Also, where can I get a good chassis ground on this car?

-Mike

mbbodytech

The easiest way would be to tap off the fuse box in either the dashboard or the rear SAM, the panel with fuses at the left rear of the trunk. MB makes some cool fuse holders that plug into the box and you can take the wire wherever you like. I can get the part number and take a pic or two to help you out - but not for a couple of days. This way is the most clean and best protected way there is!

If I don't post the info I mentioned in a few days, PM me and remind me.

Capt Nemo o2

Correct!!!

Tishers

Don't forget to put a DC power filter (aka, RFI filter) on the battery lead. Usually this is done to protect the radio from vehicle electrical noise but I would worry more about the sensitive electronics in my car.

Ham rigs can kick out quite a bit of power, you wouldn't want to freak out the ECS, ABS or Air Bag controller (*BANG* surprise!).

Also try to locate your ham antenna as far away from the antennas that are located all over the vehicle. A 25-100 watt 2 meter transmitter would very nicely blow out the front end of any receiver in the immediate vicinity.

doofoo

Hmm, that would be very interesting. I will call Mercedes about this tomorrow, unless someone else knows about these? Would they support 20amp circuit off them? Is the wire coming off the fuse block that I put in pretty large guage?

-Mike

doofoo

Yeah I will put a rfi filter on there as well. I am using my ICOM V-8000 2meter 75watt, or my ICOM 706MKIIG which puts out 50 on 2m, 100 on HF. I have a Diamond HV7A Quad Band antenna mounted on a quick detach trunk mount so I can take it off when not using it for trips. It makes my car look like it's remote control.

I am still looking for a ground I can use when mounting in the car, anyone have any suggestions?

-Mike

mbbodytech

Here is where you can get a nice power lead. I added the green one myself, for an auxiliary power supply in the rear area. However, there are three more spaces left. Here are the part numbers for what you need:

Fuse Link:

Black A 003 545 13 01

Purple A 003 545 18 01

Terminal for above fuse link:

A 004 545 52 26

Ground loop:

A 003 545 85 40

All you need is a little wire and a 20 Amp fuse and you are ready to go! The position with the green fuse link is terminal 30.

I hope this help you out.

Justinius7

what would be the MAXIMUM amperage that you can tap out of there? Say for a small amp or other power hungry unit.

20 amps = 288 watts

could someone do a 30 amp fuse? Or would additional 8 guage wire need to be brought back from up from the battery? OR could one run 2 small amps (150 and 150) putting them on 2 different fuses in the fuse block? Or does it stress out the stock wiring?

mbbodytech

Boy, you got me on that one. I'm really not sure. Maybe sunman would know - that guy seems to know everything!