Antenna Placement in ok spot?

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skatertj

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If turning the Attenuator ON makes the signal sound clearer, you are most likely experiencing front end overload or desense.
This is a vey common problem with scanners. Some are better at rejecting out of band signals and some suck. I'm not familiar with the 2055 so I can't say how well it rejects out of band signals.
Going from your comment of turning the attenuator on though does indicate an overload or desense problem.
The most common causes are FM radio stations and paging transmitters.
Paging transmitters do turn on and off so you should hear the signal clear up on its own if the paging carrier happens to drop while you are also hearing the distant VHF signal that is weak.
RadioShack sells a cheap FM Trap or FM Filter. It will help a bunch if your problem is from FM radio stations.
You will not hear the radio station but the scanner does. Its front end cannot handle the strong signal from the radio stations so it ends up worsening your VHF reception.
The radio shack FM trap only comes with F connectors so you will need adapters and a short length of coax.
I'd try that as it may very well fix your problems.
I don't know any specific threads here at RR but this has been discussed many times. Try searching for FM Trap or FM Filter and you should find a bunch of info here. Most likely the threads will be in the RadiShack or GRE forums as the GRE made radios are the most prone to this problem.
RadioShack FM Trap : Adapters, splitters and amplifiers | RadioShack.com is the link to the trap at radioshack. If that link does not work, it is stock number 15-024.
If you try this and it works, you may want a much higher quality trap. Par Electronics makes one that has the proper BNC connectors and is much higher quality over the radioshack trap. Par also sells traps for the common paging bands also but you would need to determine if paging is the cause and then what band is the culprit. Around here I must filter both the 152 and 158 paging bands but I do not need an FM trap.
If you are in a fairly large city, it could be fm radio or paging or both. More rural areas I'd think would be from fm radio stations.
162 MHz NOAA WX broadcasts are also a common cause of problems with scanners but the tower would need to be located near you usually for it to be a problem.
Here is the link to PAR, they also have a page there somewhere that explains overload or desense that may help ypou determine if this is your problem. PAR Electronics | Filters for the commercial 2 way market, MATV, FM broadcast, laboratory, marine industry, amateur radio, scanner and short wave listening enthusiasts

A strong FM radio station signal or paging transmitter can completely wipe out the signals you are trying to hear. Sometimes the intended signals sound muddy (same sound as your "fuzzy" term) but still come through and other times you may not hear them at all. Even strong local VHF signals can be totally lost if you are experiencing bad desense.
I guess "desense" would also be a good search word here at RR.

Good Luck!


Well, to maybe help you help me, I can tell you this. I am tryin to get clearer signal on frequencies between 154.0 up 156.0. These channels im trying to listen to are about 20-25 miles from me. When my scanner is in my home, stationary with the telescopic antenna, all these frequencies i want to hear, come in mostly clear. Once it is in my car, these channels need to have the attenuation button pressed to have them come in clear. Even then, when they start to come in fuzzy with ATT on, i can turn it off and itll be abit clearer then go back to being fuzzy so ATT will need to be hit, once again.
My weather nearest NOAA antenna is roughly 25 miles away. It does come in fuzzy in some places also and i know on one road, it cuts out completely til i git ATT...

Maybe this can help? i also could be wrong on this part "i can turn it off and itll be abit clearer then go back to being fuzzy so ATT will need to be hit, once again." I would need to drive around again, which i will be doing tomorrow, then i can remember if this is true or not.
 

kruser

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Well, to maybe help you help me, I can tell you this. I am tryin to get clearer signal on frequencies between 154.0 up 156.0. These channels im trying to listen to are about 20-25 miles from me. When my scanner is in my home, stationary with the telescopic antenna, all these frequencies i want to hear, come in mostly clear. Once it is in my car, these channels need to have the attenuation button pressed to have them come in clear. Even then, when they start to come in fuzzy with ATT on, i can turn it off and itll be abit clearer then go back to being fuzzy so ATT will need to be hit, once again.
My weather nearest NOAA antenna is roughly 25 miles away. It does come in fuzzy in some places also and i know on one road, it cuts out completely til i git ATT...

Maybe this can help? i also could be wrong on this part "i can turn it off and itll be abit clearer then go back to being fuzzy so ATT will need to be hit, once again." I would need to drive around again, which i will be doing tomorrow, then i can remember if this is true or not.

Going on what you said, I'd say you are definitely seeing overload or desense. The fact that they come in clear indoors with just the little whip is the key.
Your house is attenuating the offending signals but you still do not know if the culprits are FM radio stations or another strong and local transmitter near you.
My guess is that it is FM radio stations as they are always on of course.
If the NOAA tower is 25 miles away, that is not your problem.

I'd certainly try the FM Trap that radio shack sells. I bet that will fix your problems when using the mobile setup outdoors.
If the "fuzzy" sound is always there when in the car, it is almost for sure that is is an always on transmitter like an FM radio station would be.

It could also be a TV station if you have any still broadcasting in your area on VHF channels 2 through 13 and they are within a few miles (10 miles or less maybe) of your travels. It also does not matter if they have converted to digital over the air format. They can still wipe out a scanners front end.
The FM trap at radioshack is the cheapest thing you can try easily.
The needed adapters to get you back to BNC will cost more than the trap does unless you buy them online.
I guess you could buy all the stuff you need from radioshack and open the packages carefully so you can stick them back in and return if it does not work.
You are definitely experiencing overload from something and your scanner cannot handle it. That is why you hear the fuzzy sound more when you are outdoors. The antenna on your roof is picking up the intended signals better but at the same time, it is also picking up the offending signals that are causing the overload much better. A filter or trap is the only way to cure this type of problem.
You can also build what is called a stub filter using a hunk of coax and a bnc T fitting. But those filters are wideband and can kill off the intended signal if the interfering signal is near the intended signal in frequency. They can also be tricky to cut to the perfect length so I'd go for the FM Trap at radioshack first.
RadioShack will let you return about anything so I'd try this before anything else.
Do you know anyone that has a Uniden scanner you could borrow?
Unidens are much less prone to the overload problem that kills most of the GRE made scanners. I'm pretty sure the 2055 is a GRE made scanner made for RadioShack.

The problem with using the attenuator button is that it will also attenuate signals that are truly weak. Then you will lose them because you attenuated them. A trap will not attenuate the weak signals because it is tuned to only attenuate the FM radio band. Actually a trap does cause a small amount of loss but not nearly as much as the attenuator button does. It is usually not noticed at all but if it works, you will start hearing signals you never heard before!
 
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kruser

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One other simple test you can try while driving around - don't use the roof mounted antenna. Just hook the little whip on the scanner inside the car and see how the signals sound.
This is not the ultimate setup as you will lose the already weak stations but it will also attenuate the offending signal that is causing your problems and you may be surprised at what you can hear!
Leave the attenuator button turned off or out while using the whip.

Can you think of any radio or TV station towers near you?

If any of those type of towers are near you, they are the likely culprit.

Even cell phone towers that use 800 MHz and higher frequencies can wipe out the front end in a scanner even when trying to tune the 154 MHz VHF frequencies like you are. Nextel towers are more likely to wipe out the front end though as they run higher power than your typical cell towers do.

Your overload is most likely caused by a nearby tower running at say 400 MHz and below though unless something is wrong with the bandpass filter switching circuit in your scanner (highly unlikely).

The PRO-2055 is a fairly recent model and it is a GRE made radio. It's the same as the GRE PSR-400. So it is susceptible to this exact overload that you are experiencing.
Without a doubt, you are seeing an overload or desense problem. Overload and desense are essentially the same thing for this topic.
 

skatertj

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Broken Arrow, Ok
Ok well i will either try the trap, or start saving for a new digital uniden scanner haha. If i do the trap, ill let you guys know how it goes! Thanks for all the help!
 
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