Mobile Radio Wiring

ericsze · Post by **ericsze** » Sat Jan 18, 2003 11:36 pm

Best way to wire a mobile radio and to minimize engine/alternator/etc. noise would be to....?

Wire the positive to what? Ground to where?

Any thoughts?

Monty · Post by **Monty** » Sun Jan 19, 2003 12:09 am

Hi:

If you are speaking of the installation of later
Model Motorola Radio products, the best way
is to run the B+ all the way to the Battery post
( with the Fuse ) Located at the Battery post.

( IF ) the vehical has good grounds, then run the
Ground Side directly to the Chassis of the vehical.

In the majority of the installations this works just
fine.

Sometimes, a Extra Engine Strap to Chassis ground
is always desired, but most later series vehicals
already have them

If you want to have the radio go off with the ignition
I would consult the vehical Wiring Diagram, and pick
off a point on the key switch that has the avaiible
current for the radio application.

BECARFULL NOT to tie into the Computer DC lines
if your vehical has one...

Monty

Znarx · Post by **Znarx** » Sun Jan 19, 2003 5:17 am

12volt battery, no ground plane antenna..just remember to charge the battery EVERY night!!..not very practical, but it will isolate you from the vehicle..lol
all kidding aside..for ignition on/off..I prefer going striaight to the battery, with an ignition/accessory driven relay to supply the power... although this system on some radios will cause you to lose the last setting.. i.e. the radio always resets to channel 1 ...Z

Tom in D.C. · Post by **Tom in D.C.** » Sun Jan 19, 2003 7:24 am

Most of the writeups I've seen over the years recommend that you run BOTH the positive and negative wires from the radio directly to the battery and put a properly sized fuse in BOTH wires as close as possible to the battery. You can still use an "ignition sense" wire to control use of the radio with this arrangement. All of the current ham equipment, if that's what you're considering, retains its memory of the last-used channel when the power is cut off, even if all power is removed, since they use EEPROMs which are not volatile. And just to cover all the bases for you in this, be sure that the wire you use is large enough to comfortably carry the maximum current the radio will draw on transmit.

Tom, W2NJS
...in D.C.

elkbow · Post by **elkbow** » Sun Jan 19, 2003 8:32 am

My current installation is probably overkill, but safe. I'm not putting in a relay on the battery + side, but I am changing the battery terminal lug to one that will have an external 'allen head' connector for attaching 4 guage power cable. I am running all my radio's with remote heads. The 4 Guage will run to a Stinger Digital fused block behind the rear seat in my F-250 Superduty truck. I will still be using the inline fuse, but the Stinger is fused for each radio as well as providing an overall digital LED readout for voltage. My power connections are made at the Stinger, no need for running all the way to the battery will 4 different lines, only the one 4 guage running to the back.

Ground is handled by a Stinger Ground Distribution block. Again, it is a 4 guage cable running to ground, has the nice accordian plastic cover to make it look stock. Outputs on all the stinger blocks are 8 guage, but there is one 4 guage output on the Power block that won't be utilized.

As in general though, Monty had it right, run your Power connection to the battery, ground is fine on the chassis. That doesn't mean you will eliminate any alternator, iginition, etc. noise, but its a good starting point. If there is noise, then you'll need to check connections and find out where the noise is being produced, generally it is getting in on the ground side, etc. If you install any grounds that are subject to weather, make sure you use some sort of good corrosion resistant lube, such as penetrox, etc.

Mike B · Post by **Mike B** » Sun Jan 19, 2003 12:34 pm

Japanese radios like to run the red and black leads directly to the battery. As Tom mentioned, these radios also have a fused ground lead.

Think about what happens if the vehicle’s ground wire from the battery goes bad, and corrosion will usually get these wires eventually. All the current flowing from the battery will look for somewhere else to go, and it will find your conveniently provided radio ground wire. Vehicle batteries can produce enough current to melt and weld metal, start fires, etc. Without the ground lead fuse, the vehicle starter motor for example, will use your antenna mount, coax shield, radio cable/connectors, microphone clip and/or radio chassis as a ground return for its massive current flow. If so and you are lucky, any one of these may become an unintended fuse. If you are not lucky allot worse can happen.

You really should follow the manufacturer’s directions when installing any radio.

nmfire10 · Post by **nmfire10** » Sun Jan 19, 2003 3:00 pm

I take 4 pair telephone line and use that to power everything. Radios, lights, the whole shabang. Everything can then have it's own dedicated wire. And who wants to use pathetic 10 gauge wire. I'm using 22 gauge wire.

elkbow · Post by **elkbow** » Sun Jan 19, 2003 5:09 pm

Matt...not to knock your electronic intelligence, but 10 guage is much bigger (not pathetic) than 22 guage wire. 22 guage is hardly big enough for making programming cables.

jcobb · Post by **jcobb** » Sun Jan 19, 2003 5:51 pm

Quick, Matt - pull on his other leg and he'll fall down!

Sorry, elkbow, couldn't resist........

I think he was "teasin us".

Jack

ptemplin · Post by **ptemplin** » Sun Jan 19, 2003 7:37 pm

I'm no expert, but I would recommend against fusing the ground wire. If the ground fuse should blow for some reason around the same time that the 12VDC happens to short inside the radio, the case might become rather energized, which is a Bad Thing (tm).

If your vehicle's battery ground cable decides to quit, you have bigger problems than your radio ground cable.

Susan157 · Post by **Susan157** » Mon Jan 20, 2003 4:30 am

My training was always fuse both and only at the
battery.We have not had a problem with this hook-up.
The reason was already stated.

Jonathan KC8RYW · Post by **Jonathan KC8RYW** » Mon Jan 20, 2003 4:55 am

nmfire10 wrote:I take 4 pair telephone line and use that to power everything. Radios, lights, the whole shabang. Everything can then have it's own dedicated wire. And who wants to use pathetic 10 gauge wire. I'm using 22 gauge wire.

common sense wrote:22 AWG Ampacity = 2 Amps MAX

You've got to be kidding, right?

Equinox · Post by **Equinox** » Wed Jan 22, 2003 6:17 pm

nmfire10 wrote:I take 4 pair telephone line and use that to power everything. Radios, lights, the whole shabang. Everything can then have it's own dedicated wire. And who wants to use pathetic 10 gauge wire. I'm using 22 gauge wire.

You ain't that same guy that tried to make a ham radio by sticking an antenna up a pig's butt are ya?

007 · Post by **007** » Sat Feb 01, 2003 6:18 pm

Where can I get these units?!?! I need something like them badly for my 3 X9000's in the car! Please advise.

elkbow wrote: The 4 Guage will run to a Stinger Digital fused block behind the rear seat in my F-250 Superduty truck. I will still be using the inline fuse, but the Stinger is fused for each radio as well as providing an overall digital LED readout for voltage. My power connections are made at the Stinger, no need for running all the way to the battery will 4 different lines, only the one 4 guage running to the back.

nmfire10 · Post by **nmfire10** » Sat Feb 01, 2003 6:52 pm

Yes, I was kidding, and no I am not into that kinky stuff with farm animals. Sorry

007 · Post by **007** » Sat Feb 01, 2003 7:20 pm

Disregard my last post....I found their site and a couple eBay stores that will help. I never thought I'd be looking at car stereo install stuff to do a /\/\ install!

Post by **Code3Response** » Sat Feb 01, 2003 7:25 pm

007 - pass along the ebay stores! Im thinking about getting a couple of these for 1st class installs coming up. Thanks!

007 · Post by **007** » Sat Feb 01, 2003 7:56 pm

Code3Response wrote:007 - pass along the ebay stores! Im thinking about getting a couple of these for 1st class installs coming up. Thanks!

Ebay Store:

http://www.stores.ebay.com/hifisoundcon ... page8.html

Look under "Car Audio Wires, Cables, Caps"

Another site:

http://www.sfxaudio.com/products/shopBr ... nd=Stinger

Stinger's site:

http://stingerelectronics.com/sting_pro ... bution.asp

Glen W Christen · Post by **Glen W Christen** » Tue Feb 04, 2003 2:26 pm

I know Motorola at one time emphasized to NOT go to the negative battery post. Most definitatlyvery bad things happen to a radio when starter current tries to go to ground through the radio.

shammond · Post by **shammond** » Tue Feb 04, 2003 2:54 pm

West Marine is another good source for electrical distribution devices.

A little pricey but good quality stuff.

http://www.westmarine.com

Steve

Mobile Radio Wiring

Mobile Radio Wiring

Mobile wiring etc.

Fusing both legs is the BEST

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