CB runs batteries down

[ramcatdoc]

I have a Cobra 29 CB in my M1009, wired directly to the front battery. Twice now, after not driving the Tank for 10 days or so, it has run the batter down. The radio is off, but it does have a built in weather alert; i'm not sure if that has anything to do with it. The gernerators are both working, and the batteries are brand new.

I also notice that when I start the truck, the CB flickers on and off rapidly. The radio otherwise seems to be working fine.


Do these radios trickle charge? Is there a problem with wiring directly to the battery? I thought "off" was "off."


Thanks, guys.

 

[Flyingvan911]

I would suggest getting an accessory fuse block so that you can wire in several items. Put a switch before the block so you can turn off the accessories when you park. Starting with the CB on could damage it. Start the truck with your added accessories off.

 

[porkysplace]

Or just wire it to one of the accessory lugs in the fuse panel .

 

[Goose2448]

What he said. I have almost the same radio, but I have a plug on it for the power point. They all come on and go off when they first get power. I would either do what he said, or run a plug to on it and plug it into the power point.

 

[Danger Ranger]

I just put a Cobra 29 NW WX ST in my jeep, and wired it in the fuse panel. Comes on and off when I start the jeep. Like an accessory. Works fine.

I stand corrected. Thanks.
l l l
V V V

 

[nf6x]

It is both normal and recommended in the ham radio world to wire transceivers directly to the battery in order to avoid ground loops and reduce ignition noise in the radio. It is always done with independent positive and negative wires, never using the vehicle chassis as a ground return.

By-the-book military radio installations also wire directly to the battery (sometimes with an intermediate terminal block, like in the CUCV) for the same reasons. When you see an installation of something like a VRC-12 where the power cable is bolted right to the battery terminals, it was done that way for a reason.

We also fuse BOTH the positive and negative leads, so that a failing engine ground strap doesn't result in the entire operating current of the vehicle flowing through the antenna cable, through the radio chassis, and back to the battery.

That being said, if your CB radio is still drawing enough current to drain the batteries when it is turned off, then that is a problem.

 

[Goose2448]

Another thought, you can turn off the weather feature. See if that helps. Mine stays plugged in all the time, unless I am traveling and my phone needs charged. It only flashes on, its supposed to, when I plug it in. Also be ware of the weather test's on Wed at noon and Sun at 1800, they scare the crap out of you while drive

 

[Rambling Wreck]

I would suggest getting an accessory fuse block so that you can wire in several items. Put a switch before the block so you can turn off the accessories when you park. Starting with the CB on could damage it. Start the truck with your added accessories off.

This is how I have all of my electronics installed and it works great. If your CB has a "remote" wire (usually blue) then you may want to have it on a non switched power source. This may not be so important on most CB's but on something like a stereo you would lose all of your programmed channels every time you switched it off if it weren't for the remote wire.

 

[ramcatdoc]

That being said, if your CB radio is still drawing enough current to drain the batteries when it is turned off, then that is a problem.

I wired directly to the battery for the reasons you have stated. However, even when off, the radio has drained both batteries dead twice. It must use a trickle to keep the presets on and to monitor the weather frequency.

There are two fuses in the installation, although without going out to look, I don't know if they are on pos and neg wires or not. One fuse is under the hood, while the other is the one that came with the radio and is conveniently on the dash right next to the radio. I guess I could remove the fuse on the dash when I'm not using the truck.

Could I also not just install a switch of some sort in line that I could throw, cutting off all power to the CB?

 

[nf6x]

Adding a switch in the CB radio's positive lead should work fine. Then if the batteries still run down with the radio power disconnected by that switch, you have more hunting to do.

Ham radios usually come with a fuse in the positive lead of their power cable at the very least. If there is a fuse in the positive lead near the radio, we usually like to add fuses close to the battery in both the positive and negative leads. The negative lead fuse is there to protect the wiring and especially the expensive radio in case of an engine ground strap failure, as I mentioned before. That is a belt-and-suspenders approach, and the military installations I have seen do not bother with fuses at the battery.

My most recently purchased ham radio (a Yaesu FT-450D) has fuses in both the positive and negative leads, at the battery end of the cable. That's nice because it's ready to have a pair of lugs crimped on the ends and bolted to the battery for a car installation right out of the box. Except that the mobile mount is a $50 extra.

 

[tennmogger]

Many modern radios with microprocessor do not really turn off completely. The off switch just tells the processor to go into standby and it still draws current. Yes, those will run down a battery. A separate external switch would solve your problem. Or, use a relay controlled by the ignition key: Ignition off, relay opens, radio gets zero power.

A quick test: if you disconnect the CB power cord for several minutes, then reconnect it, do you hear a pop in the speaker even if power switch if off? If so, the radio is always drawing power.

Bob WB4ETT

 

[ramcatdoc]

more to the story

I'm going to continue this thread, since I started it.

First, an update: Somewhere in this chain of events, I replaced both batteries. The front battery would still discharge if left for more than a few days, even if I left the CB radio off-line. Battery store suggested alternator was not charging well. Had it rebuilt. I also exchanged the new front battery, as I think it really was defective. I also noticed the Solargizer was not running, so I replaced it with a new version of what was already there. Voila! Seems the battery is now holding a charge.... well for at least four days. Have not let the beast sit longer than that yet. Don't know if it was the new battery, the rebuilt alternator, or the now-working Solargizer. I really suspect the first new battery was defective.

But now a new problem. With a Solargizer that is working, I get terrible engine noise on the CB while driving during the day, but not at night. I have the CB wired directly to the front battery, both leads. The Solargizer is wired directly to the batteries, in series, as well. I want to keep the Solargizer, but get really bad interference.

Question: are there any in-line noise filters I can get that would help eliminate the noise, much like I have on my Telephone line to make the DSL quieter?

Thanks for your input, folks!

ARM

 

[tennmogger]

Solargizers are basically pulse generators, ie, RF noise generators! I ran one here in the ham shack and could hear it on an antenna 100 ft away. Those long connecting wires become an antenna. Sure you could load the wires with ferrite filters and even bypass the solar panel leads to ground with .005 pf caps. (but probably not bypass the pulsing leads to ground.)

Even that might not be successful. I recommend disconnecting the Solargizer when the truck is running. It's doing little good at the same time the alternator is topping up the battery. Best way would be a small relay that disconnects the Solargizer when the key is on (use NC 'normally closed' contacts). The same relay could be used to turn ON radios when the key is on (using NO 'normally open' contacts).

Bob

 

[Cleveland Iron]

I agree with tennmogger, the relay is the way to go. Besides that, if you really have that dangerous urge to run your radio with the ignition off, you can put a switch on it for auto ( with the ignition ) or manual. If you do so, add an indicator light so you don't do the battery discharge. Besides, if things die, the light could help troubleshoot the problem.

 

[CliffSegar]

What TennMogger said.

Many modern electronics never fully turn off. There is no longer a mechanical switch that stops the flow of current. Therefore something is draining the battery all day and night. The relay situation proposed is probably the best solution. Get one with heavy duty contacts (20+ amps) that can run all the aux electronics. And having one with the common pole connected to the battery, the N.O. going to the aux electronics and the N.C. to your trickle charger would give you all you are looking for.

 

[MarcusOReallyus]

Agree with the last three posts. No good thing can come from having the Solargizer connected while running, but bad things may. Relays are your friends.

Anything with an "always on" alert feature MUST be drawing power. No way around it. It may not be much, but it's something, and that something may be more than a marginal system can handle.

 

[ramcatdoc]

Just for closure's sake, I ended up installing a toggle switch in-line and attached it to the metal plate I had made to mount the radio on the dash. Works great. No more dead batteries. I just turn the toggle off when I leave the truck, and all is fine again.

 

[TechnoWeenie]

Just for closure's sake, I ended up installing a toggle switch in-line and attached it to the metal plate I had made to mount the radio on the dash. Works great. No more dead batteries. I just turn the toggle off when I leave the truck, and all is fine again.

There are timers that are available, fairly inexpensive, that will turn on/off your electronics, after a set period of time.

ON with ignition, and stay on for (2/10/15/30,etc) mins after you turn the vehicle off.

Most of them have a 30A output and 2-3 10A outputs.

Last one I picked up was less than $50, so if you have a lot of equipment, you can use that.

Just something to think about.

 

[MarcusOReallyus]

Timers have their place, but for this application, it's probably simpler to use a relay operated by the ignition switch.

 

[TechnoWeenie]

Timers have their place, but for this application, it's probably simpler to use a relay operated by the ignition switch.

Simpler, yes. proper, no.

Not when you don't have an ACCY position.

Leaving the ignition on, without running the engine, just to use a radio, isn't a good practice.

Do it right the first time.