Clean VHF/CB radio installs

It's only inductive to common mode currents on the outside of the shield. Ideally there would not be any current there. Any significant current there means the coax shield has become part of the antenna. In many antenna systems common mode chokes are intentionally inserted in the feedline.

 

Ideally is the key phrase. It’s still good practice not to coil like that.

 

Here's today's install of an Icom IC2730A in my 2021 SR AC.

I use this radio in my 4Runner also, so I can swap it out for long trips in either vehicle. Both trucks are set up the same with all the accessories / antenna / wiring in place and I can just pull the brain from under the passenger seat, unplug everything, loosen the RAM mount for the head unit / mic, and move the radio between the trucks. Antenna, wiring, data cable, mic clip, speaker in each truck - all in for $100.

Radio is under passenger seat, held to carpet with velcro. Wiring is routed inside the console and out under the passenger seat. Power is to battery and is routed through the firewall at the main harness grommet (behind the fusebox).

Antenna is a Tram 5/8 wave VHF on a TRAM trunk lip NMO mount. Annoyingly they shipped me a stainless whip and black base; I wanted a black whip to match the base but oh well... Cable is routed through the firewall at the main harness grommet (behind the fusebox).

Mic clip is a Motorola one from my old job. I cannot recall the name of the maker of the mic button I bolted on in place of the Icom's cheesy hang up hook.

Speaker is a Midland clone of the Motorola public safety extension speakers, bolted to the transmission hump. Good sound in that location and out of the way.

Head unit is mounted to the back of the storage cubby under the HVAC controls with a homemade RAM mount. By adjusting it up to the top of the cubby as shown I can still drop my phone and wallet in there (which is all I ever put there). You can mount the RAM ball and drill out the data cable hole without removing the lower console but be super careful because the airbag brain is just underneath... don't drill too far, and use short screws for the RAM ball.

 

I see you have the requisite cuts on your hand. Proof that you are a qualified radio installer!

My only suggestion would be to move the radio as far forward under the seat as possible. If you ever have a rear seat passenger, you don't want them kicking the radio. I put mine under the front edge turned sideways so that I can get to the connector for the programming cable.

 

It's about in the middle of the seat. I moved the seat forward for the pic. I also have a utility cab so no danger of a backseat passenger!

 

I got a DC just because I can fit passengers in the back. Which is unlike my '06 Tundra AC, which had a lot of virtues, but rear seat passenger space was not one.

Even at that, I put the speaker for the 2730A under the front passenger seat. My posts on my install are several pages back in this thread.

 

Neither clean, nor installed but it works as my scanner:

 

If you're interested and have money you want to spend, there is an aftermarket control head that will work with the SDS100.

The thread is here. It's a bit long since there are a lot of posts about the development of the head.

https://forums.radioreference.com/threads/uniden-remote-head-project.396539/

 

I recently put a Kenwood D710g mobile in my truck.
I wired the positive lead directly to the battery, and the negative terminal is attached to the grounding bolt next to the OEM battery. The radio body is located under the drivers seat and uses the supplied power wiring that came with the unit.
When I start the truck with the radio already on, the radio briefly dims and does a quick reset. I’m concerned if this happens frequently it may do damage.
Any suggestions? Upgrade my trucks battery? Wire the negative lead directly to the battery too?

 

I could be wrong here, but it sounds like a voltage drop, maybe your battery is getting old? My TM-V71A does NOT do this when I leave it on during truck startup.

 

My truck is only a couple months old, but it only does short trips - so maybe the battery is not getting a full charge? When the key is in the aux position I get the “check charging system” warning on my console display - I figured it was just because the engine wasn’t running, but perhaps my battery is low…
I’ll try throwing it on a battery charger. Also, I might swap the negative lead to go straight to the battery like the positive one does already.

 

What battery are you running? Stock or AGM? The ECU/alternator do not fully charge AGMs unless you trick it with a tune or something.

I agree that it sounds like the battery voltage is dropping slightly during cranking and the radio is experiencing some amount of power drop. I'm not sure if it's detrimental to the radio, but I can't assume it's good for it.

 

My ground is straight to the battery, so maybe that would help, but I think as long as you have a solid paint-free connection at the body it should be fine.

 

Try a shorter ground - there's a few grounds in the cab with a much shorter ground cable to get there.

 

You're right about the engine not running, battery not charging. This is perfectly normal. Everyone's truck does this, it's just more noticeable because it's a message on the console screen instead of small dummy light.

 

You should be okay using that grounding lug next to the battery. That's what I did with my Icom2730A and have no problems. Are you using the original wire all the way to the battery? Also, make sure that the positive connection to the battery is tight.

 

My v71a does this when I leave it on during startup. The quick solution is not to do that, if you think it's bad. My commute is about 40 minutes each way, no issues with the battery.

 

Most vehicles are going to drop voltage enough for the radio to shut down during engine crank. It's not a sign of a problem. Some radios have enough capacitance to carry them through the loss of voltage.

It's better to ground the radio as close as possible to the radio chassis. Running ground back to the battery is generally a bad idea.

 

My Elmer taught me to do that years ago and I haven’t had any issues in over 30 years with multiple vehicles and radios. Just remember to fuse both lines. With modern cars though some have Electrical Load Detectors (ELD). For cars with those you should connect to where the ELD grounds the battery to the vehicle.

 

http://www.k0bg.com/wiring.html