Using a Handheld Scanner in a Vehicle Question

[consigliori]

When I use any of my "base/Mobile" scanners in my car their reception comes in loud and clear. However, with most of my handlheld scanners there is quite a bit of interference (I assume from the engine) that makes listening almost impossible.

Example:
BC396D and Pro-433 work great in both a home and a mobile environment.
Pro-96 also works well in both environments.
Pro-528 works pretty good in a mobile environment.
Pro-97, Pro-137, Pro-74, Icom R-5, and even a Pro-2052 are just plain horrible on reception when used in a car (Have previously owned a Pro-92B and it had the same problem).

Troubleshooting I have done so far:
1)Power - Have tried from hardwired power direct from the car battery, DC power via the Lighter sockett (normally the source of engine noise) and internal power from the handheld batteries.
2)Different Vehicles - Problem has duplicated itself regardless of the vehicle I have tried it in.
3)Different Antennas - I have two mounted antennas on my car - a glass mount and a magnet mount - as well as several different HH antennas. Swapping them out makes no difference.

Does anyone else have this problem and if so, were you able to do anything to fix it?

 

[KE5MC]

Never had a radio with that problem so no fix here.

Reading all the step I would say that it's the radio's problem. Internal batteries, HH antenna and close proximity to a running motor vehicle points to a radio sensitive to electrical noise radiated by the vehicle's power and ignition system. It not coming in on the power or the ground lead of a mounted antenna because you have no direct connection to the vehicle. I would say a design issue with the radio. Internal shielding that is not present or something with circuit layout and component used design.

 

[N1BHH]

Noise from the engine compartment is normal. There are many ways to reduce them. The first thing to do before any kind of usage of a scanner or any radio for that matter, is placing the antenna in a location such as the roof, which is the best place, or the back deck. Next, be sure that when connecting to a power source, the connections are clean. After that it's a cat and mouse game of playing with different things.

Through glass antennas should really be avoided, especially the front window, because they just don't work better than other antennas. They may be "cute" and all, but there are coupling issues related to foils and tints in window manufacture. OEM and after market ducks should be discouraged inside the vehicle because they will not hear as well as one roof mounted, they do work, but not as good. Mag mounts are good, I use several in different applications. Permanent mounts are better. I am in the process of buying mounts with teflon jacketed coax which are a step forward from coax.

The size of antennas does matter, as far as Low Band goes, you need a big antenna. For everything else you can use something smaller.

You can read many previous posts here and find what people have done to cure noise. The difference will be night and day when you explore all the components of a vehicle. Some computers send all kinds of trash throughout a vehicle and can drive you crazy. In the old days, it used to be simple, plugs and wires, now it's more a nightmare.

My way of looking at it is simple, noise is not interference. Noise is internally generated by the vehicle, interference is caused by a radio or something electrical/electronic. There is a distinction between the two.

 

[CrabbyMilton]

I have a pair of UNIDEN BC250D's that a take in the car with me once in awhile and never seem to have a problem with electrical noise from the engine so I am sorry that you are having a hard time witht this. I use the standard "ducky" and a sound feeder which works great.

 

[LEH]

Have you done any (or had any) work (mods, etc) on any of the radios that might have opened the shielding in the radio? That is all I can think of. Something in the radios themselves that makes them susceptible to the interference.

I don't have any of the radios that are causing you problems so I can't help there. Over the years, I've never had interference run across vehicles though I have had one car that was just plain downright NOISY.

 

[consigliori]

Thanks for the Tips and information. I'll take a closer look at what might be causing internal noise from the vehicle and see what works.

Thanks again!

 

[letarotor]

I've noticed some pretty heavy interference from some vehicles that have noisy electric fuel pumps. Chevy pumps seem to be worse than Ford, you can actually hear them running when the key is turned on. If its engine noise you're getting, try a new set of heavily insulated ignition wires and noise supression spark plugs. And as one viewer has already mentioned, pitch the through the glass antennas (they are worthless, especially on tinted windows which acutally have metal in the tint which supresses the passing of the signal). Drill a hole in the roof or trunk lid and put in a decent antenna, nothing can beat the real thing.

Mark