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View Full Version : CB install... with issues. (Long.)


acidchylde
06-26-2009, 03:14 AM
I'm just going to link to the gallery of images I put up instead of embedding them in the post. It's also going to have all the details. But here's the general story:

I got my Uniden Pro 520XL installed a couple of weeks ago with some help from my roommate. 'Installed' means power from battery into cab and antenna coax from bed mount into cab. I haven't stuck anything down yet because I can't decide on a good spot, but more importantly after I got everything in I discovered some engine noise issues I would like to get fixed before making things permanent.

Basic description: Power is pulled directly from the battery over 12 gauge wire, except the last little bit at the battery where I spliced in the inline fuse off the radio (which is whatever gauge that comes out of the radio - 16?). I put a ring terminal on the battery end and connected it to the convenient bolt on the top of the battery terminal. The ground I ran to the same bolt grounding the battery, again with a ring terminal. Power comes in through an existing hole in the firewall, wires end in a molex so I can move/relocate the radio easily.

Antenna (a 4' Firestik II) is mounted center on the front bed rail (right behind the cab) using the important half of a typical mirror mount. It comes down between cab and bed, goes in through an existing hole in the back of the cab that was enlarged a little to clear the connector. Coax is roughly 10' long total. The mount requires grounding since the bed is plastic and the rails don't contact any metal. I ran more 12 gauge wire (more on that in a minute) down to the frame - an unused nut that was welded on the rear cab mount. Paint was cleared off and it is a good connection.

All the pictures and slightly more details are located here (http://pics.livejournal.com/acidchylde/gallery/0001pkek).

The Problem:
Throughout the process I was checking grounds and it seemed like we were good everywhere. I went out the next day to a wide open area to tune the antenna with a SWR meter (cheapy from Radio Shack). I did it with the engine off and was able to get to about 1.4 on Ch 1 and 1.6 on Ch 40. Not ideal, but still pretty good.

Then I fired the truck up and got some horrible engine/ignition noise over the speaker. The popping/clicking is directly related to engine RPM, so I'm sure (insomuch as someone who doesn't know what the hell they're doing can be) it's the plugs firing. It took about a third squelch to get rid of it, and it was still in the background whenever receiving. Later that night I checked grounds again and got less than consistent results. My friend really trusts his meter, but I have a hard time believing that little section of wire between battery and fender ground has 6 Ohms of resistence. We did a quick test powering the radio with a cig adapter and he said that helped a little (I didn't hear the test as I was under the truck).

Also, I'm only testing electrical ground, not RF ground. A lot of people say you need a braided grounding strap to do it right, including the local CB shop, and that 12 gauge won't come close to cutting it. Except I was also under the impression you couldn't tune a badly grounded antenna, and my cheap meter says mine is tuned. What's weird to me is that I haven't done anything I haven't already seen someone else do, yet none of them reported any problems. Maybe they didn't think it was?

I'll also note that the following day on a trail run up in the hills the noise went significantly away until I got back down into town. During my intial tuning, I did not get a response to a radio check request on 19 a mile from the interstate, but that might have been nobody responding as likely as them not hearing me. On the trail people could hear me (don't know how well or if there was any noise on their end). At this point I'm still not sure if I have both a power and RF ground issue or just one or the other.

SO, I've got three thoughts on how to try and fix my noise problem.
1. Different ground for the radio - everything else seems to have its own ground, maybe that would help.
2. Braided grounding strap for the antenna. Except I can't find retail straps longer than a foot around here, so I have to find a place that sells it by the foot (I'll probably need about three).
3. Power filter for the line going to the radio. Likely cost me half as much as the radio did.

Any ideas/suggestions would be greatly appreciated.


And if you have any interest,

Radio Mounting locations:

http://pics.livejournal.com/acidchylde/pic/000hg3kk

Red: I'd lose the coin tray, but I don't use it anyway. The problem is to get it back deep enough I'd have to cut on not one but two panels (red x's), eliminating two of the holes for the tray clips. It's also all kinds of awkward angles and curves of plastic to deal with.

Green: I have it sitting here right now, but it needs securing. I can't cut into the back of the panel because there's a computer and/or duct right behind it. This means it pushes out over the cup holders more than I'd like. Can't really mount to the top of the space because of the cig outlets and odd curve to the panel.

Blue: At first this would have been ok - pull up the little rubber mat, cut a hole in the console underneath, and mount the radio vertically. It would fit such I could leave a lip to drop a rectangle of something over the hole, put the rubber mat back in, and you'd never know. Problem is that by the time you add the coax connection on the back the radio is sitting too high for me and could interfere with the shifter.

Yellow: Inside the console. Not really ideal for getting to the controls, but it does fit until you add in the coax again. There's space under the console I might be able to relieve that, but it still seems less than ideal.

I could also slap it on the passenger side of the hump, but it's kind of far away and it doesn't look very clean to me. So, still debating. First I just want it working cleanly.

Chalkie
06-26-2009, 05:32 AM
Personally, I would go with the green location. That is where I have the head unit for my ham radio mounted. To mount there you can use the 3M foam tape (pretty permanent) or you could use heavy-duty velcro (holds well, less permanent). If you are going to put any holes back there, be careful, the air bag controller is right behind there.

The only place I am aware of that sells grounding strap by the foot is HRO in Denver. Not much help, I guess.

Have you tried taking the radio ground back to the battery directly?

While you have an antenna, another option (the one I took) is to get a Firestik NGP (no ground plane) antenna. It is meant to mount on motor homes and boats without grounding required.

mrdoug
06-26-2009, 08:41 AM
I just use the cig lighter to power mine. I get engine noise unless I tweak the squelch, but when I use my radio, I'm usually on the trail and can jack up the squelch with no ill effects, so I live with it.

For mounting, and keeping in mind I have an 02, I just put it under the passenger seat with an external speaker behind the seats in the ex-cab. I've found that I rarely need access to the controls for my use of the radio.

:2cents:

RedRunnertc
06-26-2009, 09:54 AM
Can you boil it down to the reader's digest version for us ADD impaired? :D

I get noise when the air compressor comes on, pretty good the rest of the time. From my car audio days, I know it's critical to sand the paint off and make sure your "big 3" grounds are all good.

RockyMtnHigh
06-26-2009, 10:41 AM
Can you boil it down to the reader's digest version for us ADD impaired? :D


:lmao: Cliff notes?

I just use the cig lighter to power mine. I get engine noise unless I tweak the squelch, but when I use my radio, I'm usually on the trail and can jack up the squelch with no ill effects, so I live with it.


I am not sure why that happens, but I did mine to the fuse panel with an add-a-circuit and was getting feedback from it, not much but it kind of whistled when throttling. I read that you could eliminate that by running the power directly to the battery, sure enough it worked.

CoTacoTRD
06-26-2009, 12:04 PM
I actually powered mine off of the Mirror adjuster switch. But then again I have the Cobra All in the Hand unit requiring much less draw. I only get feedback when I have it on and adjust the mirror. Since I am the only driver of my truck they are pretty much set for life.

acidchylde
06-26-2009, 12:52 PM
Personally, I would go with the green location.


Green is my favored as well, I just wish that stupid controller wasn't right there.

It's at least a place to try for strap. I was going to check with Mountain States up here first. My roommate has/can get some, but it's 1/2" wide instead of 1".

You mean to the battery post itself? No, haven't attempted that yet - will probably make it part of my testing.

And I did consider that I might have to go the NGP route, I just wanted to make sure I've done everything free/cheap first.

I get engine noise unless I tweak the squelch,

Prior to this in two other vehicles I've always used the cig adapter and never had much noise (maybe the power windows), and definitely never had to crank the squelch like this. The real problem is that just stops the constant background - I still hear the exact same noise at roughly the same volume whenever receiving. Also, I use mine on the highway and tend to fiddle a lot with squelch and RF gain, so for me I need the controls somewhat accessible.

I read that you could eliminate that by running the power directly to the battery, sure enough it worked.

I wish I knew why it wasn't for me. That's exactly why I didn't want to tap the fuse panel or anything else, because I'd heard so much about it introducing noise. I'm wondering if the wiring routes in the truck just have built in filter somewhere.

But then again I have the Cobra All in the Hand unit requiring much less draw. I only get feedback when I have it on and adjust the mirror.

I've been considering if a new radio might be needed, but... Interesting that you only have feedback with that circuit activated. Or rather, makes sense and would be expected, but I've got noise from several circuits. Where did you tap it at?

acidchylde
06-26-2009, 12:59 PM
Can you boil it down to the reader's digest version for us ADD impaired? :D

I get noise when the air compressor comes on, pretty good the rest of the time. From my car audio days, I know it's critical to sand the paint off and make sure your "big 3" grounds are all good.

Sure:

Power is direct from the battery terminals. All grounds (radio power, antenna radio, antenna frame) are electrically good as measured with a multimeter. Antenna is tuned to about 1.5 across all channels. There is NO noise with the engine off. Key on (not ignition) generates a little noise. Windows up and down generate noise (but I expect this). Main problem is a constant popping/clicking when the engine is running that takes 1/3 squelch to kill, but is still there whenever receiving. The frequency of the noise is directly proportional to engine RPM, leading me to believe it's spark plugs firing.

Everything points to power/ground issue and not antenna, but I don't know enough about RF (or electrical for that matter) to know for sure which is the culprit.

fjcruzer
06-26-2009, 01:20 PM
http://i174.photobucket.com/albums/w84/fjcruzer123/cb%20install/march26025.jpg

Small piece of 1/4" ply above the headliner, all of the wiring run down the a-pillar. You can look at it Sunday. Mine is grounded inside the cab and isolated from the battery by a separate fuse block. I get the compressor noise too, but can squelch it away. You can also run a ground from the antenna mount to the frame. I've seen a few folks have poor antenna grounds in the center of the bed like that, or you can remount it somewhere with better contact.

RedRunnertc
06-26-2009, 01:59 PM
All grounds (radio power, antenna radio, antenna frame) are electrically good as measured with a multimeter.

How did you test? Just check continuity?

The thing is that you can show continuity, but might be at a different "base" voltage, and that's where the noise comes from. There needs to be as little resistance as possible for the elctrons to make the return loop back to the battery.

CoTacoTRD
06-26-2009, 03:04 PM
I've been considering if a new radio might be needed, but... Interesting that you only have feedback with that circuit activated. Or rather, makes sense and would be expected, but I've got noise from several circuits. Where did you tap it at?

Pulled the mirror switch out and tapped it right there near the switch. The amp box for the CB is under the cup holders in the center. Grounded to an internal ground point along with other items. Hand held part comes out of that cubby you show in read with the clip mount screwed into the dash. If you are down at the Wrench a thon on Sunday I can show you what I did.

acidchylde
06-26-2009, 05:39 PM
Small piece of 1/4" ply above the headliner, all of the wiring run down the a-pillar.

I've thought about mounting up there too (there's room even though I have a console there), just wasn't sure how I felt about the mike/cord. I also figure I will eventually add another fuseblock for lights/winch/etc, but wasn't there yet. I have run a ground from antenna mount to frame (in the details and pictures), I'm just not sure if it's good enough. Given the plastic construction of our beds, the only other location option is back by the tailgate in the bed, and that will cause problems for me later (shell).

How did you test? Just check continuity?

This is where I don't know enough (or have forgotten) about electrical to answer. Probably yes, just continuity and only at one (the minimum) voltage setting. Basically just touch leads different places, if it got close to 0 it was good, if it barred out as open it was bad, and that reading of 6 (Ohms I thought) was not ideal. My roommate owns the meter and does wiring for a living, but he works in a different environment (aircraft), so somehow we can't ever get on quite the same page when talking about the same things (different tolerance scales as to what's good or bad, etc). I'll try to do some more tests.

Pulled the mirror switch out and tapped it right there near the switch.
If you are down at the Wrench a thon on Sunday I can show you what I did.

I totally forgot that was constant. We went over the interior fuse block looking for constant power and didn't find one (was going to use one of those fuse taps). I'll have to try a couple of options and see if they're better.

Unfortunately I'm not able to make it down there Sunday because of a prior conflict, so i won't be able to see yours or FJs setup. Sucks, because I'd like to meet some more folks and do some learning. And I was thinking about seeing if you still had and were looking to get rid of your stock mid-engine skid - tin is better than nothing for me at this point. :)

Chalkie
06-26-2009, 06:13 PM
Green is my favored as well, I just wish that stupid controller wasn't right there.

It's at least a place to try for strap. I was going to check with Mountain States up here first. My roommate has/can get some, but it's 1/2" wide instead of 1".

1" or 1/2"... honestly with my ham rig I have NO additional grounding, other than direct to battery, and have NO noise on transmision or reception.

You mean to the battery post itself? No, haven't attempted that yet - will probably make it part of my testing.

Yes


I've been considering if a new radio might be needed, but... Interesting that you only have feedback with that circuit activated. Or rather, makes sense and would be expected, but I've got noise from several circuits. Where did you tap it at?

My CB is connected to the cigarette lighter, and like Doug said, I can deal with it. Even with the NGP antenna, I get noise when I shift gears, first turn on the truck or when the ABS kicks in. I think a lot of that has to do with the "fly by wire" that is true for all the new Toyota's.

CoTacoTRD
06-26-2009, 06:43 PM
I totally forgot that was constant. We went over the interior fuse block looking for constant power and didn't find one (was going to use one of those fuse taps). I'll have to try a couple of options and see if they're better.

Unfortunately I'm not able to make it down there Sunday because of a prior conflict, so i won't be able to see yours or FJs setup. Sucks, because I'd like to meet some more folks and do some learning. And I was thinking about seeing if you still had and were looking to get rid of your stock mid-engine skid - tin is better than nothing for me at this point. :)

I will have to check with my Dad to see if he took them to the shop or not. You are welcom to them if he still has them. But I don't know if the scrap metal guy got them or not. they won't have any bolts though as most of the stock bolts were reused on the All Pros.

acidchylde
06-27-2009, 04:20 AM
1" or 1/2"...

CB shop and a few people online said 1" ground strap for the antenna, because RF works differently than electrical. I know jack about RF, it just seemed a reasonably cheap fix to try. :dunno: But I know 12 gauge was plenty sufficient for grounding it on a different install I did... I do think you're right about the fly by wire issue.

You are welcom to them if he still has them.

Much appreciated, thanks for checking, and let me know. Bolts won't be an issue.


SO, update. I did more testing tonight. First my grounds are (I think) electrically good everywhere - radio power to battery, antenna to radio, and antenna mount to frame. They all show 0.1-0.2 Ohms from various points (don't ask me where that six came from, I couldn't duplicate it). And I learned a bit more about how to use the friggin' meter (which for reference is an older HP auto-ranging model).

Tried a couple of power options: I only get the noise when the engine is running, and it doesn't matter whether I pull from the battery or the cig adapter. Going to try a power filter tomorrow and see if that works, maybe move the antenna around a little.

Chalkie
06-27-2009, 08:15 AM
Without getting too indepth on antenna theory, a true ground plane antenna uses radials at the bottom of the antenna that are 1/4 wave length and more is better, up to 120 of them. Now, that is not very practical on a vehicle, not to mention it would just be fugly to look at. So instead, the metal body of the vehicle is used as the ground plane. I say that, because our truck beds provide nothing towards ground plane.

The ground plane provides a reflector, to reflect the radiated power back to the antenna. Using channel 20 as reference, 1/4 wave length is about 108.5". The combined length of the hood and roof come close. Ideally, the best mount you could have would be an NMO mount smack center in the roof. Most people, myself included, do not want to do that. So the compromise is to get as much ground "back" to the antenna as possible. Therefore again, more is better, and thus the comments on 1".

In your case, I would take 1/2" from where you have the wire now, and 1/2" from under each bolt at the ends of the rail, back to a ground point on the cab. Also use 1/2" on each side of the hood back to the body. Additionally, use 1/2" to ground the body of the radio itself to the body.

Truthfully though, that is a lot of work, and may not gain you much. It really depends on how you intend to use your CB. If it is for "trail use" only, you are most likely good with what you have. As Doug said, on the trail, squelch out the engine noise and you are still going to hear people that are reasonably close.

Being the resident nag and towncrier in favor of ham radio (we will now pause for a commercial break), I would actually encourage you and ALL the members here to get ham licenses and radios. The difference between CB and ham is kind of like difference between string between tin cans and cell phone. :D Believe me when I say that if I can pass the test, anyone here can pass the test with a modicum of study, and a radio can be had for the price of a good CB.

Case in point, running Tincup Pass last weekend, I could, and in fact did, talk with a friend in Colorado Springs by way of the repeater on top of Pikes Peak. Talk to someone that far away on CB (intentionally - I don't mean skip), I dare you. :cool:

acidchylde
06-28-2009, 12:57 AM
Truthfully though, that is a lot of work, and may not gain you much.

Being the resident nag and towncrier in favor of ham radio

First, I hear you on the ham, I've seen all those arguments and believe them, I'm interested and plan to eventually... but it's more than I want to get into right now and I still have a need/use for CB.

That does sound like a lot of grounding. :) After today, I was thinking I might do more more ground to the same place other side (so both rear cab mounts) and call it good as it's going to get. I did some reading on the Firestik site this morning and they even say 12 gauge should work, but if I can find the strap for a reasonable cost I'll use that 'just in case'.

First up today was a power filter (and an expensive one at that) - it didn't do squat. Same noise, same level. I tried using some of the strap in place of the mount grounding wire, no change. We grabbed a handheld scanner and moved it around the truck and it picked up the same noise, better in some places than others. Based on that I tried moving the antenna around, still no change. I played around with moving the radio's power ground to different points, including battery post - still no change. Decided to take truck power out of the equation and brought out a clean bench power supply plugged into a wall socket - NO CHANGE, still the same noise at the same level. (All of this with engine running - still no problems with it off).

So at this point I will add the other mount ground and make them both braided strap if I can find some reasonably priced, possibly use some to connect body and frame as suggested. And then I'll live with the noise until a) I feel like buying a NGP antenna to try out, b) get hold of a different radio or antenna setup to test, or c) get my radio into a shop to be 'checked out'.

devinsixtyseven
06-30-2009, 02:24 PM
Get the NGP antenna, or mount your current antenna on the front bumper (assuming it's metal, or you have an ARB or something), or do up a mount to set it on the side of the fender, next to the hood where it won't prevent the hood from opening. Any of these things will save you headaches and testing.

Not as good as the roof, or behind the cab with a metal bed, since it'll project more backward than forward, but on the trail that shouldn't be a big deal.

-Sean

acidchylde
06-30-2009, 04:02 PM
Front bumper is plastic, replacement is coming but a ways off. NGP is probably the best bet, I'm just feeling cheap if I don't know for sure it would make the noise go away. Stupid plastic bed. Thanks for the suggestions!