You might want to realize that even professional radios have problems like this
SDS100/SDS200: Filter problems with no resolution..
- Thread starter chad_96
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Especially if they're close to being out of range.
Ubbe
Member
Where I live I have no system that are line of site and I can only receive reflections that bounce off obstacles and terrain. One day it can be full signal strength and the next day it barely opens squelch depending of the weather situation. When it rains the signals strengths improve as the trees on the ridge of the mountains that surrounds my valley get their leafs wet that then works as reflectors for radio signals and bounce them down in the valley to me. If an airplane pass overhead I can get an amazing signal for a few seconds.
When its windy I can have a good signal for few a seconds but then it can go totally dead for the next couple of seconds when the trees sway in the wind. I can receive systems clearly at a -100dBm level and the scanners sensitivity when it opens squelch are something like -115dBm. If you have -90dBm up to -70dBm if should be fine, if that are the signal strength of the actual frequency and not interference it measures.
A directional antenna with some gain like a yagi could work good as it points to the source of the signal and doesn't pick up too much from the sides and rear that could interfere, working like a filter in itself. If you go with a discone they usually only work good between 100MHz to 500MHz as its horizontal elements are tuned to something like 300MHz and at 800MHz reception could be down by 10 to 15dB and the antenna that came with the scanner could actually work better even if you have that discone higher above ground.
If you have a discone indoors you can buy the cheapest $50 Tram discone as most discones perform the same. If it doesn't work good at 800MHz you can cut the horizontal elements down to half size as that will restore full gain at 800MHz but lose performance below 200MHz. If you cut to 2/3 size it will still be good at 800MHz but 900MHz can be worse but you will have full reception down to 150MHz. You can always mount the cut pieces back on using hoose clamps or something similar. Where those horizontal elements points are its direction of reception, so you can cut only the ones that point to the 800MHz sites and any VHF sites will still be received at full strength from other directions.
For a troublesome digital system that are hard to receive, and change over the course of a day, you can try and program its control channel, or voice, as analog only and listen to the data signal and try and hear if it gets distorted from any interference, or if it just goes weak with lots of noise that then will need a better antenna.
/Ubbe
When its windy I can have a good signal for few a seconds but then it can go totally dead for the next couple of seconds when the trees sway in the wind. I can receive systems clearly at a -100dBm level and the scanners sensitivity when it opens squelch are something like -115dBm. If you have -90dBm up to -70dBm if should be fine, if that are the signal strength of the actual frequency and not interference it measures.
A directional antenna with some gain like a yagi could work good as it points to the source of the signal and doesn't pick up too much from the sides and rear that could interfere, working like a filter in itself. If you go with a discone they usually only work good between 100MHz to 500MHz as its horizontal elements are tuned to something like 300MHz and at 800MHz reception could be down by 10 to 15dB and the antenna that came with the scanner could actually work better even if you have that discone higher above ground.
If you have a discone indoors you can buy the cheapest $50 Tram discone as most discones perform the same. If it doesn't work good at 800MHz you can cut the horizontal elements down to half size as that will restore full gain at 800MHz but lose performance below 200MHz. If you cut to 2/3 size it will still be good at 800MHz but 900MHz can be worse but you will have full reception down to 150MHz. You can always mount the cut pieces back on using hoose clamps or something similar. Where those horizontal elements points are its direction of reception, so you can cut only the ones that point to the 800MHz sites and any VHF sites will still be received at full strength from other directions.
For a troublesome digital system that are hard to receive, and change over the course of a day, you can try and program its control channel, or voice, as analog only and listen to the data signal and try and hear if it gets distorted from any interference, or if it just goes weak with lots of noise that then will need a better antenna.
/Ubbe
Did it end up being a hardware change, or was it a setting? My SDS200 frustrates me to no end sometimes, and then performs like a rockstar with little or no change. Honestly, if it decoded and received as well as my 436HP does, I would be super happy.
None of the above. And back to the same stuff. Flipping filters as usual.
I'm convinced, or I should say have convinced myself that I need to just figure out a way to have an outdoor antenna as high up as possible. I think that will make the only difference, or at least help a lot.
I feel like the filter issue is ultimately tied into the Antenna signal/strength, and quality of antenna. I've asked others who said they had this going on as well if they were using indoor or outdoor antennas. Everyone states Indoor. So, now just figuring out an antenna that is worth a crap outdoors other than a yagi that only points at a specific site, as I got 2 on both sides, and have been warned discones are not really worth a pinch of owl **** on 800mhz.
If I get any results, somehow, I will surely update you.
Discones are unity gain, so not the greatest. Only real option for a gain antenna besides a Yagi, is a collinear. They can get stupid expensive though!
Yeah thats what I've been reading in several threads about the discone. Especially for the 800mhz band.
Yeah, I keep seeing and have had many recommendations for the yagi. That wouldn't be much of a problem if I didn't rely on 2 site on opposite sides of each other. Not sure how that would work if a yagi was to be used.
Never heard anything on a collier. Going to have to give that a look.
Thanks for the heads up and advice!
This is on E-bay.... No experience with it.
Thanks
Joel
L-COM 800/900 MHz 6 dBi Omnidirectional Antenna 900Mhz Used | eBay
L-COM 800/900 MHz 6 dBi Omnidirectional Antenna 900Mhz Used.
www.ebay.com
Thanks
Joel
So, I did take it up there yesterday when I went to scout the area and see what kind of area and obstacles may exist to contend with.
So, granted it was 100 degrees yesterday I couldn't much stand to be up there to long. But, it did seem it was doing pretty good. That could also be a fluke, as I had just previously got the filter switched up, and working well. So, Not too sure.
Attic doesn't seem to be a good option for an antenna ad there is a very large old furnace unit up there that sits dead center and obstructs the area, unless something was set on top of it, maybe.
Thanks for that, much appreciated.
Was actually just considering pulling the trigger and purchasing this and figuring out how to run it outside and hook it up. 800 MHz UHF Vertical Outdoor Base Antenna (851-869 MHz)
I was not going to respond anymore but being human I hate to see anyone throw money in the garbage these days. Ugh, No, that antenna is overkill, add good cable and connectors and maybe an amp at that frequency and its 200- $300 You can’t try to overcome propagation physics or atmospheric conditions to solve a “filter problem“, but if money is no object, enjoy. You are reaching the point of what I call “diminishing returns”.
My very final observation, if you are generally receiving acceptable voice from your two sites, why do you even care about filters, rssi, errors or antennas? No reception is perfect all the time.
End of my advice.
My very final observation, if you are generally receiving acceptable voice from your two sites, why do you even care about filters, rssi, errors or antennas? No reception is perfect all the time.
End of my advice.
So, I will sum it up the best I possibly can for you, as a newer individual into this hobby.
First, overkill would be an acceptable term. However, I had a seasoned member on here reach out to me. He made a coverage map based on my area,and sites, regarding coverage area. Looking at his maps I couldn't agree more that, if even off some, are from what I've been able to gather, spot on. I don't believe that antenna would be as much "overkill" as much as beneficial due to my area.
As far as fixing a filter problem. Well, I have nothing on the issue that could be a logical answer to it. Simply, if I can throw money at it to make it better even some, sure, whatever.
Acceptable voice from my 2 sites. Well, yes I do, could be for an hour could be for 6 hours. Then back to flipping through filters to find the best one...again. I'm a pro at getting those filters flipped through at this point. Uniden should consider hiring me to do a fast tutorial video on how to switch them at this point.
Why do I care about filters,rssi,errors or antennas. No reception is perfect all the time. Well, because that's what makes this grand sds line of scanners tick. Instead, I had people blowing smoke up my ass telling me it was the best of the best and top of the line. What they didn't say was that if you don't have simulcast, this isn't for you, and will save you a lot of time and issues. But, do you think Uniden, or anyone who sells Unidens products is going to be honest..??? Hell no, they want the money and could give 2 ****s about any of their consumers.
I appreciate your logical opinions, and you taking the time out of your day to respond. What I don't care for is, if you wanted to throw your weight around and smart mouthed opinions, probably more so for the fact you can look amazing for doing so to your buddies on this forum, I could care less. If newer people who aren't as savvy on this stuff and ask too many questions is an issue, tell your admin buddies to make it a rule. Then you and that other clown wiener lips or whatever they call themselves can make up the rules as you go along. I ain't playing that game no longer..
I have no “buddies” on these forums. I have communicated privately with almost no one except for members from my state.
Until now, I enjoyed helping you where I could with no other motives. I make up no rules. I don’t throw my weight around. I am not a clown. I play no games. I and many others just try to help with no paycheck or reward except for an occasional thanks. Please think about your words before you write.
Done.
Until now, I enjoyed helping you where I could with no other motives. I make up no rules. I don’t throw my weight around. I am not a clown. I play no games. I and many others just try to help with no paycheck or reward except for an occasional thanks. Please think about your words before you write.
Done.
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