BCD396XT: Newbie seeks help to improve reception

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wakker200

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This is my first post here. I've been reading through the forum and trying to find information that might help apparent reception problems I'm having with my brand new BCD396XT scanner.

First off, I'm trying to listen to a P25 system in Linn County, Iowa. I have used FreeScan to program the radio, and although I'm not done with setting up quick keys for groups, I have set color alerts for many of the agencies that I'm monitoring. I also have replaced the rubber ducky with a Diamond RH77CA antenna. The squelch is zeroed.

Google maps tells me that I'm 13.9 miles from the tower north of Marion, and we live on top of a hill.

What's happening....

The reception I'm getting is frequently choppy. Sometimes the signal level meter is showing 4 bars or more but I'm not getting any audio. Sometimes the alert light will come on and I'm getting no audio.

I have run the auto performance (threshold?) setting routine as described in the easier-to-read manual. I tried setting the 800 MHz band modulation from NFM to FM, then changed it back because it seemed like that killed everything. I have tried programming this as a mixed system but read somewhere that our new system is a straight P25 system so changed it to that.

I have played around with the delay times (not knowing what I'm doing) but those haven't made any difference that I can tell.

So. If anyone has any suggestions for me to try, I'm all ears. Things have truly changed since I studied communication electronics back in the vacuum tube days. It's frustrating to have this expensive new piece of high tech gear that many here say they love that doesn't perform as well as my old RS analog 800 MHz scanner did pre-trunking.

Thanks in advance.......

Bill
 

teufler

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first if you have a two story house, go to the top floor and check if reception ius better. vhf and uhf works better with height. assuming that this is done, a small beam antenna, cheap, like the tape measure beam that if you search on google for tape measure beam, the instructions and photos are there. i have one and it comes in handy. I have prepared a file, with Freescan 2.16a, linn cty that has cedar rapids and linn, in addition there is cedar falls, iowa city . yoiu are only on the east of cedar rapids so you should be able to copy. Where I live, 800 mhz works, with a Condor antenna, about 20 miles, as I have hills between my location and the rest of the 800 towers. vhf p25 is alittle further. Again this is with an Austin Spectra Condor antenna. Nothing outside, though I do have a dual band Diamond antenna for my amateur gear which allows a much further reception. Every 10 feet of an antenna height increase, you will notice an improvement. make sure the squelch on the 396xt is set to around a 2, as while I read your thread, I checked mine and somehow it was at 15. I had noticed some choppy signals.
 

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wakker200

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Thanks!

Thanks for the replies.

First off, JamesO... the firmware is up to date. It shipped with the newest firmware in it. Do you think the RS antenna is better than the one I bought (Diamond RH77CA)? It was recommended in another thread. The same company also makes one that provides a 2.5 db gain...

teufler... I have seen the single beam antenna. We live in a single story home but I could get on the roof with the scanner and see if things improve. (I would think that reception would have to improve with height). I would be willing to put an antenna either on the roof or inside the attic if that's what it's going to take to fix this.

I will try your file and let you know how it works out. I'm east of CR in the Mt. Vernon-Lisbon area.

Thanks again!

Bill
 

popnokick

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Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 7_1 like Mac OS X) AppleWebKit/537.51.2 (KHTML, like Gecko) Version/7.0 Mobile/11D167 Safari/9537.53)

TV antennas work for this too. Don't feel you have to use a special scanner antenna or beam / Yagi. In fact if you have an existing TV antenna get an F to (whatever 396XT connector is) adaptor and hook up your TV antenna coax cable to the scanner. If things improve, go on the roof and turn the antenna so the elements / rods are vertical and attach it back to the mast. If you don't have a TV antenna go buy one and some RG6 coax. Compared to "special" scanner antennas it will cost less. Mount it on your roof (preferred) or if you don't want to deal with grounding and lightning, put it in the attic. Run the cable down to your scanner and use the adaptor to connect. TV frequencies are close enough (and may now actually be) to what you want to receive on your scanner. HDTV changes a couple of years ago put big chunks of UHF & VHF into reallocation for public safety radio comms. 700 mHz was a large part of it, as well as other UHF and VHF former TV channels.
 

teufler

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the tv antenna would work. I totally forgot a tv antenna as most of us have cable now and we don;t see tv antennas much around here . highway 30 towards cedar rapids is pretty flat so you don't have high hills between you. I thought you were north of CR, so the file I sent has Cedar Falls and Waterloo stuff. Digital signals do have some garble and chop to them. but you have a cable and hope you can hook up to the computer. I still have a serial port as my computer is home built. I do go through a usb to serial convertor though. But if temporarily you can go on the roof, to check out the radio, then an outside antenna will solve the problem. The outside antenna I have is 6.5dbd, not 2.5dbd. Its a diamond . Diamond also makes a discone D-130J. If height improves your reception, then you can research your antenna selection.
 

JamesO

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First off, JamesO... the firmware is up to date. It shipped with the newest firmware in it. Do you think the RS antenna is better than the one I bought (Diamond RH77CA)? It was recommended in another thread. The same company also makes one that provides a 2.5 db gain...
Put the stock antenna back on the scanner for now and see what happens.

I bought a 996XT from someone an they had the Diamond RH77CA on the radio, I thought the front end of the radio was dead, could not pick up much in the way of 800 MHz systems. Moved to the RS 800 antenna with a 90 degree BNC adapter and NIGHT and DAY difference.

But you may want to explain the "problem(s)" with your reception and what you are trying to monitor.

My 396XT is my current hand held scanner and seems to do fine with the exception of some issues from time to time with simulcast.
 

ofd8001

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It sounds like you might have the dreaded simulcast distortion problem. If your scanner is showing 4 bars of signal strength, but you don't hear anything or what you hear is garbled, that's a good indicator of simulcast-itis.

Your scanner's reception is fine (actually probably too good). Rather the problem is with the scanner decoding what it receives. The scanner is receiving two (or more) transmitters and the signals are arriving slightly out of sync with each other. It's sort of like the radio version of "Echo Canyon" where it's hard to make out what is said.

One thing you can do to confirm this is really a simulcast distortion issue is to take the scanner close to one of the sites (as in perhaps 1/4 mile away). If you are hearing clear transmissions, that's highly suggestive of simulast distortion.

In the old days (I too am a product of electrical engineering school where you had to take a class on how to use a slide rule), the answer for poor reception was a better/taller antenna. But simulcasting (multiple transmitters using the same frequencies) is a whole new ball game and you have to go against the conventional wisdom.

What you want to do is diminish your scanner's ability to receive. So try using the stock antenna and set the attenuator for the site to "On". That may lead to improvement.

I've seen other posts suggesting a Yagi antenna pointed directly toward one site or even fashioning a paperclip for an antenna.

You may also try getting into the "hidden" menu settings and changing the P25 Adjust Mode and P25 Adjust Level. One has to do a lot of tinkering to come up with the best possible combination - what settings work good for one place for one system may not work as well for another place/system. (For my local simulcast system settings of 13/175 yield the better results, but they ain't perfect). When you do tinker with the P25 settings, be patient - it is a trial and error process with lots of combinations to dial in the best settings for your system and where your scanner is.
 

wakker200

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Still a work in progress

Thanks to everyone for your thoughtful responses.

I haven't got onto the roof yet but I'm going to try to do that this afternoon if time permits. (Wouldn't you know there was snow on the roof this morning!)

My current plan if reception is acceptable on the roof is to put antenna there and run a cable down to hook up to ou cable TV wiring which we no longer use. We stream our TV now using Roku boxes.

There is a cable connection very close to both places I want to use the scanner, so if that fixes the problem it's just a question of which antenna and getting the adapters from f to bnc.

ofd8001... You raise an interesting point about too much signal. I just turned on the attenuator and I'll run like that for a bit to see how it works. I have already been into the threshold settings and I believe you when you say patience is not optional with those settings. I read an article about that yesterday; the author said that you should have all other reception factors solved before working with those numbers. Apparently there was a proposal at Uniden to make the radio continuously self-tuning, but it was not possible due to the finite number of R/W cycles you get with an EEPROM.

I will get back to this thread as soon as I can determine whether height and antenna type solves the problem.

Thanks again for the suggestions!

PS. I'm from the slide rule generation, too. Back then a huge leap in technology was when they developed circular rules.
 

wakker200

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Flummoxed

Well, I took the scanner onto the roof yesterday and unfortunately I'm not any better off on the roof than I am in the living room. I really dislike heights, btw.

I couldn't detect any difference in the scanner's behavior at all. While I was up there I tried both the RS 283 and the Diamond RH77CA with the radio's attenuator off and on. I also tried several combinations of P25 adjust settings. The radio was still turning on the alert light and showing steady 5 bars on a regular basis with no audio.

When I got back inside, I tried straightening out a paper clip guess what... It seems to deliver as good performance as any of the 4 antennas I've plugged into it. Still seeming the alert lights and 5 bars with choppy reception or no audio at all. Hmmm.

The police use radios with duckies all over the area, so I'm perplexed as to why their radios work (apparently better, according to the Chief) when mine is behaving so poorly at the top of this hill.

Is there any possibility that I'm trying to scan too many county agencies and that one or more of them is transmitting a signal that the radio can't decode at 5 bars and therefore I'm just missing other transmissions? I will test that theory by locking out any 5 bar channel with no audio signal.

Also, I find the suggestion that multiple frequency transmissions could be causing me problems. Can I fix this by removing secondary frequencies from the radio OR by using a multi-element antenna? There's a paper clip in the antenna socket right now and it's picking up as much as ever.

Thanks in advance for any thoughts you can offer on the topic.

Bill
 

JamesO

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Sounds like you have the scanner in a Close Call mode or something.

I cannot even recall what it takes to get the Alert light on my 396XT to light up.

Suggest you just figure out how to do a factory reset on the scanner, then press and then just try to monitor a Weather channel or regular FM broadcast station.

The issue with these scanners is you can paint yourself into a corner pretty easily and think the scanner is broken when in fact is is doing EXACTLY what it has been instructed to do.

Also suggest you read this - Easier to Read BCD396XT Digital Scanner Manual
 

wakker200

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OK, will try another reset

Thanks for the suggestion regarding the easier to read manual. It's really the only manual that I've been working from.

As far as the alert light, I found that simply setting the light in Freescan didn't do the trick. I had to set it from the radio menu. However, there may be a way to do it from Freescan that I just didn't discover yet.

Thanks,
Bill
 

wakker200

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Works great as an FM radio

I just cleared the scanner and programmed in two FM stations.

It's working great, even with the paper clip for the antenna.

Hmmmmm......
 

teufler

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You got me think that less is more. So if you have done a reset on the scanner, the file attached is just, only linn cty, 1 red control frequency, cc only, id search mode, so no ids in groups. We are letting the radio decide everything. If this works, then you can build on this. I had to dump everything once because i had told the radio something, that the radio , if it could talk would have said "do not compute".
 

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wakker200

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Can't open file with FreeScan

Hi, teufler,

I unzipped the file but FreeScan doesn't like it. Is there some other software that will open it?

Thanks!

Bill
 

ofd8001

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The police use radios with duckies all over the area, so I'm perplexed as to why their radios work (apparently better, according to the Chief) when mine is behaving so poorly at the top of this hill.

Is there any possibility that I'm trying to scan too many county agencies and that one or more of them is transmitting a signal that the radio can't decode at 5 bars and therefore I'm just missing other transmissions? I will test that theory by locking out any 5 bar channel with no audio signal.

Bill
I'm pretty sure based on what you've found is that your issues are related to simulcasting. This is a relatively new concept of radio systems. That's where a system uses multiple transmitter sites, all operating simultaneously on the same frequencies, to cover an area.

In the old days, they used to have one transmitter with lots of radio horsepower and a very tall antenna, just so the radio signal would penetrate buildings and go over hills. With the radio spectrum being so finite, a new concept had to happen, which was simulcasting. Now the the same footprint can be cover by using multiple sites with less tall antennas and less radio horsepower. With that concept, it means the spectrum is less congested and frequencies can be used closer geographically.

Users of the system (police, fire and EMS) have radios that are much better at decoding overlapping signals than scanners. But their radios probably cost $2,500 where a scanner is $500-600.

As a former fire guy, I loved our simulcast system. It was clear and had coverage in a lot more places than the old system. But I hated it when I tried listening to it with a scanner because I got so much garble or places where my scanner wouldn't decode the audio. I tried the things previously mentioned (attenuator, P25 settings) and it helped, but did not eliminate the problem. I don't know if you've run the full gamut of P25 setting combinations, if not, keep trying those.

The new line of Uniden scanners (the x36 models) are far better at dealing with my local simulcast system. They aren't perfect like my old fire radio was, but much better than my 996XT was.
 

teufler

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Well the file unzipped fine here , so its small, you can create it very fast. Go into freescan and file new, then create a site. The site type is 800 mhz type 2, and chech the block control channel only. Then go to trunk frequency and put in 851.225. Thats all there .under system type, id search. Thats it, send to the scanner.
 

JamesO

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I just cleared the scanner and programmed in two FM stations.

It's working great, even with the paper clip for the antenna.

Hmmmmm......
Now either go to a Weather Scan option, or program a few NOAA Weather channels in and see what happens.

I DO NOT think you have a simulcast problem, it could be a problem, but unless I missed something you are not receiving ANYTHING with 4-5 bars on the signal meter?

If this is the case, you are programmed incorrectly.

I am sure there are some local systems in your area or adjacent to you that may not be simulcast so you can sort these out.

Hint, start simple, then worry about trying to program in a Trunked system.

If you have any VHF trunked systems, they have their own issues, work on 800 MHz systems first.

Likely you just figure the scanner out.

Also for starters, but the scanner in ID Search mode rather than ID Scan mode. You should pick up all traffic on a Trunked systme in ID Search mode, then once you figure out what ID's you want, program them, then change to ID Scan mode.

Initially you want too much traffic, then you want to cut it down to what you really want to monitor.

Also note if you DO NOT program Quick Key Sites then the scanner will scan ALL systems/frequencies.

But this is all a learning curve, it may take you weeks or months to master the scanner.

I am still working on sorting all of mine out, however, I keep jumping from the 396XT to the 996XT to the 536HP and then occasionally back to the HP1.
 

ofd8001

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If you are up for a little experimentation, you can try creating a new CONVENTIONAL system. For frequencies, enter all of those that you see as System Frequencies for the Linn Iowa system in the RR database:

Linn County Public Safety (Project 25) System Trunking System, Various, Iowa - Scanner Frequencies

After you have done that, hit scan for this conventional system. Hopefully your scanner will stop on the control channel (sounds like a machine gun or motorboat running). Lock that channel out and continue scanning.

If you scanner stops on the control channel, that confirms you are within reception range of the system. Then monitor the system for a while to see if you receive any transmissions.

What you would be doing is listening to the system's frequencies for diagnostic purposes. You won't be following the trunking groups so conversations may be disjointed. Still this is a good way of confirming you are in range of the system. Just getting the control channel is very helpful knowledge. If that's coming in "solid" then we'll have more information to work with.

Another thing you could do that might be informative is to look at the follwoing two sites which show the transmitter/tower locations for the Linn simulcast system:

WQPX837 (LINN COUNTY RADIO GOVERNANCE BOARD) FCC Callsign Details
WQPX838 (LINN COUNTY RADIO GOVERNANCE BOARD) FCC Callsign Details

If you can estimate the distance from where you are located to the nearest three transmitter towers, that might be helpful.

I always did like a good radio mystery :lol:
 
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