how to get rid of interference

[kc9neq]

i have a bcd996t scanner and i am using a radio shack scanner antenna (20-176) mounted outside.

i live in a metro area where there are all types of communications are being used.

when i am scanning the railroad band. i am receiving some type of interference. the interference sounds like a pager tone followed by a humming noise or morse code.

i am also having another problem. i was listing to a railroad dispatcher 161.460 when the local pd 155.070 broadcasted. as a result i heard the railroad dispatcher, the pd dispatcher, and the local noaa weather band all n the 161.460 channel.

i have not use attenuator setting in he scanner. if i do so will it reduce the reception range of the channels in the scanner.

i addition the bcd996t scanner has a range setting which is graduated in miles like 10, 20, and so on.

what does this setting do and if in increase the range from 10 to 20 will it make a difference in reception.

 

[ka3jjz]

You hit the nail on the head when you said 'pager tone' - it's quite likely you're getting some intermod problems from overloading. That would also explain your issue with the 155.07 transmitter. It's not bad enough to desense the radio, but it is causing mixing issues which results in the junk you are experiencing.

Insofar as the pager is concerned, a filter - PAR electronics sells them, among others - will do the job quite nicely. We have a couple of links for these in our Wiki. The PARs are a bit expensive, but quite highly regarded.

73s Mike

[edit] For some specific links to filters, check our Milcom equipment page at:

http://wiki.radioreference.com/index.php/Milcom_Receiving_Equipment

 

[aar9sm]

Intermod

You are not alone I brought this up months ago nobody else had the problem or cared to admit. Now I am starting to see a lot more of this type of complaint in the BCT-15 and the BCD996T, my 780 or my ham equipment as very little when compared to these two. If enough people start complaining about this issuse maye just maybe Uniden will fix it or at least finally admit it.

Mike

 

[Dubbin]

i addition the bcd996t scanner has a range setting which is graduated in miles like 10, 20, and so on.

what does this setting do and if in increase the range from 10 to 20 will it make a difference in reception.

That is only going to be for GPS settings and will do nothing unless you have a GPS hooked up to the radio. You can read about it in the manual.


Mike, problems like this do not exist for every user because of monitoring locations. Its really not a problem with the radios, the problem is in your location and how much crap you have floating around in the air around you.

 

[kc9neq]

i have since used the attenuator setting on the railroad 161.460 and it seems to have fixed the problem on that freq, but the problem still exits on the other railroad frequencies programmed into the scanner.

will the attenuator cut down on the range of these frequencies if i use it?

i can attenuate each frequencies or attenuate the radio itself, which is better?

also i think that the radio has one general attenuator setting.

i was using a rs pro 95 with the outside antenna and experienced the problem every once in a while and thought that the outside antenna was overloading the handheld.

i bought the bcd 996t thinking that since it was newer, it was better, and i would be able to receive farther than the pro 95.

now i am not sure.

 

[jrs71]

More intermod

You are not alone I brought this up months ago nobody else had the problem or cared to admit. Now I am starting to see a lot more of this type of complaint in the BCT-15 and the BCD996T, my 780 or my ham equipment as very little when compared to these two. If enough people start complaining about this issuse maye just maybe Uniden will fix it or at least finally admit it.

Mike

I have had the same problems with intermod on my BCD996T. My intermod is coming from a 158 MHz paging system. I can attach the same outside antenna used with my 996 to either my BC898T, BC246T, or PRO-2096, and don't have the intermod problem with those scanners.

Randy

 

[kc9neq]

this problem really sucks. the bcd996t was pretty expensive. i beginning to think i made a mistake by its purchase.

if anyone can direct me who to complin to i will.

to the UPman or uniden or both?

 

[LarrySC]

In most cases the problem is the lack of use of the PL/DPL Tones. Actually some Rail freqs use PL TONE. Norfolk So here in SC uses some PL Tones. All Public service VHF/UHF uses PL Tone. When tone is used it stops freqs that do have a tone, like digital pagers, from completing the path thru the scanner to the speaker. A scanner antenna that is not frequency specific will allow odd freqs to enter the scanner. An antenna that is cut for VFH/UHF/800 will ATT FM Broadcast, 900 mHz pagers, etc. Good Luck.

 

[jgodeker]

I also have the BCD996 and experience "pager tone" intermod on the 155-174 VHF bands. However, I live only 12 blocks from my local police/safetycenter/transmitter site.

J.

 

[kc9neq]

i found my offending pager frequency. its 158.100. does anyone know how i can find out who is using the frequency in my area? i live in st. louis mo metro area.

 

[RoninJoliet]

That garbage is all over this country, 158.10 and 453.1250 another garbage freqy (doctors pager) is on Provena Hospital down the street from me.....I purchased a adjutable attenuator at RShack, put it in line and it helps....Bob Grove sells the $79.00 notch filters that are super in critical situations and really help.....

 

[iMONITOR]

That garbage is all over this country, 158.10 and 453.1250 another garbage freqy (doctors pager) is on Provena Hospital down the street from me.....I purchased a adjutable attenuator at RShack, put it in line and it helps....Bob Grove sells the $79.00 notch filters that are super in critical situations and really help.....

You are correct, and that is the reason for these filters. Here is the link for the PAR Filters sold by Grove:

http://www.grove-ent.com/filters.html

They are very effective, providing you choose the correct one for your particular problem.

 

[iMONITOR]

You are not alone I brought this up months ago nobody else had the problem or cared to admit. Now I am starting to see a lot more of this type of complaint in the BCT-15 and the BCD996T, my 780 or my ham equipment as very little when compared to these two. If enough people start complaining about this issuse maye just maybe Uniden will fix it or at least finally admit it.

Mike

All scanners marketed though retail are affected by this type of interference. It's not unique to Uniden. That is why companies like Grove sell PAR filters, to eliminate the problem for those that encounter it in their area. I supposed if you wanted to pay something like $2,000.00 for your next scanner, they could remedy this internally.