Ignition noise through scanner?

[dmg1969]

I recently (Saturday) installed a Bearcat BC355N in my 2009 Hyundai Tucson with a SpectrumForce Wideband antenna. I am just using the cigarette lighter adapter for power. The scanner is constantly locking onto frequencies (usually VHF low) with constant static. Adjusting the squelch does nothing. It will persist for 1-3 minutes and then the static seems to sputter out almost like I was driving through an area of interference. I also have experienced it locking onto frequencies in the 150s MHz and UHF in the 400s MHz. Those are more of an electrical buzzing noise that sounds like a data channel.

At first, I thought it was the antenna, but I went out on lunch and experimented while driving. When it locked onto a pure static VHF low frequency, I pulled over and shut off the ignition to accessory and the static went away. I did that like 3 times and it seemed to go away each time I turned the engine off.

How can I solve this? The frequencies I want to monitor are VHF low, VHF, UHF, air and CB. I do not need 800 MHz. Right now, the scanner is pretty much useless for my mobile use.

Keep in mind that I am just a scanner hobbyist, not a ham so please be detailed. Thanks!

Dave

 

[ab5r]

No offense intended, but the cigarette laigher outlet is probably the worse choice that you could have made. Running a wire of sufficient guage directly to your battery with a fuse inline is much better. Also, be sure that your radio is grounded to the car.
Best Regards

 

[buckent]

you'll need to install an ignition noise suppressor kit on the leads to the radio power..

as the other poster said, cig lighter power is probably the worst place to tap in for power.. I run 4 radios in my car, a conventional scanner, a uniden 996XT, a 2m/440 ham radio, and a galaxy CB, and all 4 of them are run to a separate fuse block under the dash that is fed directly from the battery, and switched by a relay wired into my ign switch.. no noise, and I have a nice clean signal when I transmit.

 

[dmg1969]

Well, like I said...I am not one to tinker with vehicle electronics. So, I can just use the supplied DC power cord and run red to positive and black to a ground on the vehicle? I was looking at the manual and I noticed a disclaimer about not using the cigarette lighter adapter in a positive ground vehicle. I called Hyundai and they say it is NOT a positive ground.

Edit: I have never tapped into the fuse block before. I would assume that is preferable than just running the red of the DC power cord to the battery. Looking online, I found someone who installed a scanner by tapping into the fuse panel using a fuse tap. Is this the proper way to do it? If so, I can handle that.

Dave

 

[ab5r]

Reluctantly, I agree that you can use a tap at the fuse block. The direct to the battery is best, but you are not supplying a transmitter, only a receiver. And, in some cases as the man suggested, you "may" have to get an ignition noise suppestion kit, but rarely.

Good luck.

 

[DigitalSandwich]

First, I would start by determining if the noise is coming in via power or antenna.

You said turning the engine off eliminates the noise, so this should be easy to determine.

1. HOLD the scanner on the noise, and disconnect the antenna. Does the noise go away? If it goes away, the noise is coming in through the antenna, and you need to fix the antenna side.

2. If it does not go away, it's probably coming in from the power side. To verify this, connect the scanner power to an independent power source, such as AC/DC power supply or separate 12V battery. If the noise goes away (on the same problem frequency), then the noise is coming in through the power side.

For #1, you can try relocating the antenna AWAY from the problem area. Typical problem areas are, engine, I/P, and fuel pump area. If this does not work, you will need to determine what component in your car is making the noise. For this, you will need to start turning off one component at a time by pulling one fuse at a time until you find the source of the noise. Once you find that source, the actual fix depends on the actual part causing the issue. Pulling fuses can have some bad consequences, so this is only recommended if you have some basic understanding of automotive electronics.

For #2, you can try installing a power filter between the cigar adapter and the scanner. If this does not work, you can also try direct connection to the battery in addition to the filter. If it still doesn't work, you will need to hunt down the noise source using the fuse method above.

With that being said, with today's vehicles containing more and more electronics, it may be nearly impossible to eliminate all of the noise. With my particular vehicle setup, I don't bother with anything below the air band (108MHz), because the vehicle is very noisy down there.

Let me know if you need any additional help.

-DS

 

[dmg1969]

DigitalSandwich: I actually did answer the question about disconnecting the antenna in my original post in the Antennas section. On the way into work this morning, when it locked on a frequency with solid static, I reached down and disconnected the BCN connector of the antenna wire and the static stopped. I waited a second or two and then connected it again and the static returned. I want to try that once or twice on the way home to confirm it. Then, on the way in to work tomorrow, I want to just use either the back of the set antenna that came with it and see what happens.

That is why I am so confused. At lunch I did run out and did a few experiments of turning the ignition to accessory when it locked on to a frequency with static. 3 out of 3 times, the static stopped when I did that. I am sure there there is some ignition noise, but I don't know if that is what is causing the static lockup.

If I could solve that, I have no problem hard wiring the scanner to the battery.

I will do some tinkering tonight and post back later tonight or tomorrow.

Dave

 

[dmg1969]

Well, I am really at a loss. If I unplug the antenna from the back of the radio, there is absolutely no noise. I took some videos and put them up on YouTube showing the various things I am talking about. The best video would not download due to the size I guess. But there are 3 different videos which show what I am talking about.

Static interference on Bearcat BC355N with SpectrumForce Wideband antenna - YouTube

Unknown interference on Bearcat BC355N - YouTube

I have one more that I will add once it finishes uploading.

 

[DigitalSandwich]

Dmg,

Sorry, I missed your original post. It sounds like you are getting the interference via the antenna. In which case, no power filter on the scanner input nor direct connection to the battery will help you.

I think I saw in one of your other posts that you didn't have enough coax to run the antenna to the back of the car. So, it may be difficult, but if you can get another antenna, or borrow one from someone else, I would recommend you try other antenna locations on the vehicle to see if it works any better. Typically, the front side of the vehicle is the hot spot for electrical noise.

Otherwise, you need to figure out which component is causing the noise in your vehicle, and fix that component (pull fuse method). I had to do the same thing with my Geo Tracker when the fuel pump was interfering with 11m operation. In my case, a bypass capacitor close to the pump did the trick.

One thing I noticed is that your coax looks really thin; much thinner than traditional RG-8X or RG-58. Could it be poorly made coax used on the antenna picking up the noise?

I hope that helps.

-DS

 

[dmg1969]

Well, I did some testing. I unhooked the roof antenna and did not hear a peep out of the scanner the whole way home from work. This morning, I just plugged in the back of the set antenna and used that on the way into work. I did pick up some low band static interference, but not as bad as with the external antenna. Some of the shorter bursts of static I chalked up to radio transmissions that could not be pulled in by the back of the set antenna.

Tonight, I want to run an extension cord out to my vehicle and use the AC adapter to run the scanner with the external antenna to test if it is the vehicle power causing the interference.

I think my next move is to hard wire the scanner to the battery this weekend. If that does not work, I will return the SpectrumForce and try a different external antenna.

DS,: yes, the coax on that antenna is very thin. You are correct. I tried installing the antenna back near my hatch, but the 12 feet of cable would not reach the front where the scanner is. So, I opted to put it where I did for ease of getting the cable into the passenger compartment.

P.S. Here is the other video of what the scanner is doing. This was the best example I got yesterday, but it took a while to download.
http://www.youtube.com/watch?v=MgZpVzyEWo8

 

[popnokick]

Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 6_0_1 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/6.0 Mobile/10A523 Safari/8536.25)

Haven't watched video yet but your symptoms read to be same as what I experienced with scanner in my car. Spent weeks thinking it was ignition or alternator then found the real culprit.
I use my cellphone in my car and have this nifty 12VDC charger that plugs into my cigarette lighter and gives me a USB port so I can connect anything that charges via a USB cable. It's a high current fast charger and works great.
Except it is RF noisy as hell. Particularly in VHF low band. Causes heavy static that can't be squelched out. One day in the middle of all the static I unplugged the USB charger from the 12V outlet and POOF! Noise gone. Plugged it back in and noise reappeared. Rinse and repeated... same thing.
I've noticed it's worse when battery on device on USB is in low condition requiring more charge. Solution? None except to unplug the charger.

 

[W2NJS]

One additional possible problem area is the fuel pump, which these days is usually located within the gas tank and can be a serious source of RF hash. In your case you would probably need help from an electronics shop if that's the problem, but time and again, after people have gone through what you're now going through, they end up finally checking the fuel pump and it turns out to be the culprit.

 

[dmg1969]

popnokick: I thought about that too. I have a cigarette lighter to 2 USB adapter. I have tried a lot. I turned the radio off, unplugged the phone charger and even turned off my cell phone. Nothing. Good idea though. I just got back from Radio Shack and buying their mobile mag mount antenna. Gonna throw it on my car on the way home and just put the cable in through the window and crack it. That should tell me once and for all if it is the SpectrumForce antenna.

Dave

Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 6_0_1 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/6.0 Mobile/10A523 Safari/8536.25)

Haven't watched video yet but your symptoms read to be same as what I experienced with scanner in my car. Spent weeks thinking it was ignition or alternator then found the real culprit.
I use my cellphone in my car and have this nifty 12VDC charger that plugs into my cigarette lighter and gives me a USB port so I can connect anything that charges via a USB cable. It's a high current fast charger and works great.
Except it is RF noisy as hell. Particularly in VHF low band. Causes heavy static that can't be squelched out. One day in the middle of all the static I unplugged the USB charger from the 12V outlet and POOF! Noise gone. Plugged it back in and noise reappeared. Rinse and repeated... same thing.
I've noticed it's worse when battery on device on USB is in low condition requiring more charge. Solution? None except to unplug the charger.

 

[dmg1969]

Yeah, I remember someone else mentioning the fuel pump. I hope not. I'm not going to get into a whole, expensive fix for a $99 scanner. If it's as simple as putting a relatively inexpensive filter on, I will do that. We shall see.

One additional possible problem area is the fuel pump, which these days is usually located within the gas tank and can be a serious source of RF hash. In your case you would probably need help from an electronics shop if that's the problem, but time and again, after people have gone through what you're now going through, they end up finally checking the fuel pump and it turns out to be the culprit.

 

[dmg1969]

OK, so I threw the Radio Shack antenna on my roof and used that on the way home instead of the SpectrumForce. There was noticeably less interference, although there were still 4 instances where it locked onto a VHF low frequency and had nothing but static. The reception was much better in low band and I was hearing some VHF frequencies in the 155.xxx range from several counties away.

I pulled the SpectrumForce antenna off and am putting that in the mail today to return. I also pulled the Radio Shack antenna off until I can permanently mount it rather than run the coax through the window. I am also going to hard wire the scanner. I kind of have to at this point because, in my haste to clip the zip tie (tie wrap) holding the cigarette lighter adapter wire, I put a nick in it with my diagonals. I'm thinking that doing that, hopefully any remaining interference will be gone. If not, my last idea is an in-line noise filter for either the power or antenna.

Dave

 

[dmg1969]

For those of you who advised me to hard wire the scanner in, I am going to do so this weekend and have some questions.

Some recommend direct to battery while others say it is OK to go to the fuse block. I am not positive that I have a good, direct path from the passenger compartment to the engine compartment. I'm not comfortable drilling through the firewall. So, it is more than likely that I will tap into the fuse block. Is there still a possibility of interference by doing that which i could avoid by going direct to battery? I see different types of fuse taps and have worked with none of them. Some are fuse bodies that plug into the fuse box and the fuse plugs into it...and has a pig tail wire with crimp connector attached. I also see what is just a metal blade that fits over the fuse and has a male spade attached. You them attach a female connector with a pigtail. Is there an advantage to either type? Also, what is the best fuse size (Amp) to tap into? I guess I have to look at the in-line fuse of the DC power cord to see what size that due is and just tap into one of that Amp size in the accessory fuse box?

Sorry for all of the questions, but I do want to learn so I can do it myself. The last scanner install I had done I paid a guy like $50-$75 for something that probably took a few minutes.

Dave

 

[dmg1969]

OK, I am driving myself (and you guys I'm sure) NUTS. Some people say to go the fuse box and some say direct to battery. Some people are telling me that direct to battery is a fire hazard. Anyway, I would like to use an Add-A-Fuse and go to the fuse box. That seems very simple. Now my question is which fuse to use. I am thinking about using the 15 AMP for the rear power outlet (cigarette lighter).

There is already an inline fuse in the DC power cord for the scanner. I don't know what that fuse is rated at. I will have to look tonight.

To use the Add-A-Fuse, I pop the existing 15 AMP fuse and plug in the Add-A-Fuse (see photo). There are slots for 2 fuses in the Add-A-Fuse. The original 15 AMP fuse goes in the side without the pig-tail. My question is the size of fuse to use for the new circuit that will power the scanner. I know you don't want to use a large capacity fuse for a small wire. So, if the inline fuse is, say a 2 AMP, I would have the original 15 AMP fuse plus a 2 AMP fuse on the side with the pig tail for the new circuit for the scanner?

 

[dmg1969]

I talked to my wife's friend's husband, who is a mechanic. The plan is to use the empty fuse slot meant for the heated seats (which my vehicle does not have). Going to put in a fuse tap and a 5 AMP fuse on the new circuit for the scanner.

Dave

 

[WA0CBW]

That should work. As a 2-way radio shop we would normally recommend connecting the equipment through a fuse directly to the battery or the accessory battery terminal. The fuse should be located as close to the battery as possible. Just like the fuse panel in your house is usually located very close to the electrical meter (source of power). The difficult part can be bringing that wire from the engine compartment into the passenger area.

The connection directly to the battery will eliminate most interference created by the car's electrical system. As stated earlier you can check this by disconnecting the antenna with the car running. If the interference is still there it is probably being generated by the cars electrical system. Then connect the scanner to a separate battery. If the interference goes away then it is most likely caused by the car's electrical system.

As a 2-way radio dealer we also recommend connecting the negative power lead from the equipment to the negative side of the battery as well again using a fuse in the negative lead. Practically the negative lead would be connected to the point where the battery negative lead is connected to the car frame. This is done because today's cars don't necessarily have all parts of the frame/body connected together at the same point causing ground loops. The fuse in the ground lead at the battery is to protect the equipment from the high starter current should the connection between the battery and the car frame be damaged or removed.

BB

 

[dmg1969]

Thanks for the information, BB. Like I said earlier, I got such conflicting opinions...go direct to battery, no...that's fire hazzard...blah, blah, blah. I think the fuse tap is the simplest method for me so I can use the supplied fused DC power cord. It's only 6' (so they claim), so to run to battery, I would need to splice to lengthen it to reach the battery. According to my mechanic friend, there should be a ground handy right there. I will just need to crimp a ring connector onto the end of the black lead. Just hoping this takes care of the noise. Swapping out the antenna got rid of a good bit of the interference.

Dave

That should work. As a 2-way radio shop we would normally recommend connecting the equipment through a fuse directly to the battery or the accessory battery terminal. The fuse should be located as close to the battery as possible. Just like the fuse panel in your house is usually located very close to the electrical meter (source of power). The difficult part can be bringing that wire from the engine compartment into the passenger area.

The connection directly to the battery will eliminate most interference created by the car's electrical system. As stated earlier you can check this by disconnecting the antenna with the car running. If the interference is still there it is probably being generated by the cars electrical system. Then connect the scanner to a separate battery. If the interference goes away then it is most likely caused by the car's electrical system.

As a 2-way radio dealer we also recommend connecting the negative power lead from the equipment to the negative side of the battery as well again using a fuse in the negative lead. Practically the negative lead would be connected to the point where the battery negative lead is connected to the car frame. This is done because today's cars don't necessarily have all parts of the frame/body connected together at the same point causing ground loops. The fuse in the ground lead at the battery is to protect the equipment from the high starter current should the connection between the battery and the car frame be damaged or removed.

BB