SDS100/SDS200: SDS100&200 Global Filter Setting spreadsheet

[ratboy]

The bandpass filters would help a lot with that too. It's super sensitive, at least on 700-800, and actually in my apartment does a great job on lower VHF hi freqs, but on railband, it's pretty sad, any of my other radios will pick up continuous traffic from NS and CSX with a rubber duck and the SDS 200 is mostly silent It seems to lose it about just about 159 MHZ, where it will weakly pick up a weak Monroe Mich simulcast on 159.030, but the much stronger (on any other receiver) NS dispatcher on 161.070 is only heard if the squelch is off, and barely even then. Meanwhile my old GRE PSR-500 sitting nearby with the rubber duck is getting both the dispatcher and part of the time, the trains too. Oh well, maybe some filters will help cure that, maybe not.

 

[seth21w]

Try wide inverted on all your rail frequencies.

 

[Romeomike2709]

Try wide inverted on all your rail frequencies.

This works for me.

 

[bravo14]

Try wide inverted on all your rail frequencies.

I may have to try this..

 

[bravo14]

Here is what I have set up for filters

Conv - Wide Normal (analog & digital)
Trunk Edac FL SLERS - Wide Invert (Provoioce)
Trunk - Wide Normal (Analog & Digital)
Custom Search - Wide Normal (Analog & Digital)

 

[TurboRob]

Ohh... Filters I'm enjoying try and error. Gives me a good perception of what's to come. Was able to get a glimpse of a p25 Simulcast near by for the first time last night using wide auto/normal but still too high of db.

Sent from my Pixel 2 XL using Tapatalk

 

[K5mow]

I fine for myself. I leave the filter off. I also get a much stronger signal when the filter is off.




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[TurboRob]

I've noticed stronger signals coming without filters but clearer transmissions with filters on. I must express to all of you guys my great enthusiasm on finding me a new hobbie.

Thanks Dave !!! You're the man

Sent from my Pixel 2 XL using Tapatalk

 

[RF23]

All most of us can do is share our experience with the filters.

I have had weak signals disappear when using the filters, but others actually got stronger.

I have had moderate level signals get weaker but with much less error therefore better decode occurred and one system it actually got almost 20db stronger with the use of filters. I expected it to disappear with filtering.

So, in my opinion, you have to experiment with your radio & antennas with the systems you monitor from your location and even the conditions can play a role.

Good Luck.

 

[Ubbe]

The automatic gain control in the scanner also comes into play.

It will reduce the total gain when it sees a strong signal. If it where only one single frequency active in the air it wouldn't need any type of filters in the scanner. If a neighbouring channel are active it will add to the energy that the signal strenght meter uses and will indicate a stronger signal. If a filter selection will reduce the neighbour channels signal it will indicate a lower signal strenght but the decode quality will improve as it is less interfered now. If the neighbouring channel are further away in frequency it will not affect the signal strenght meter but the AGC will reduce the gain that affects all signals and the one you are trying to monitor will dissapear if it was weak to begin with. Selecting the proper filter will filter out that interfering signal and the AGC action is restored to give more gain and the monitored frequency appears again.

It's impossible to tell what filters to use at what frequencies as everone needs to test in their own enviroment. But it could be some situations, like VHF airband, that in most cases needs the FM broadcast band 88MHz-108MHz to be filtered out to improve reception and that setting could generally be re-used by the majority of users.

/Ubbe

 

[W6KRU]

Do the SDS models actually have AGC? There are no AGC settings and the terrible audio levels act like there is no AGC.

 

[SteveSimpkin]

Do the SDS models actually have AGC? There are no AGC settings and the terrible audio levels act like there is no AGC.

The AGC function is built into the Rafael Micro R836 tuner chip used in the SDS100/200.

http://dvbpro.ru/wp-content/uploads/2017/10/Rafael_Micro_R836_High_Performance_DTV_Silicon_Tuner_Datasheet.pdf

 

[Ubbe]

The AGC that you can set in some scanners are for the audio level. The SDS series has a receiver chip that has RF AGC built into the chip and according to the spec of the chip it seems that it cannot be disabled. Steve Holloway made a spectrum display app that uses the extra USB connector that are connected to the DSP and the spectrum display show that the AGC action have an impact on the monitored signal depending of the signal strenght of surrounding frequencies and how the filters are used. A video shows how artifacts are popping up on the display while tuning around the frequencies like any other SDR chip receivers and that will also make filter selections more unpredictable.

Free Scanner Software

/Ubbe

 

[iMONITOR]

Lindsay was one of the first to inquire with Uniden about the filters. Maybe he'll join us and bring us up to date with his findings.

 

[W4KRR]

In the Sentinel software, under "Edit Profile / Miscellaneous", does the "Global Auto Filter" setting override those that you make when editing the Favorites Lists sites and department settings? Or do they work together, or do the site/department settings override the setting in the Profile?

 

[W6KRU]

If you set a Site filter to Global, the site is set to whatever the Global setting is. If the Site filter is set to something other than Global, that setting overrides the Global setting.

 

[maus92]

I've noticed stronger signals coming without filters but clearer transmissions with filters on. I must express to all of you guys my great enthusiasm on finding me a new hobbie.

Thanks Dave !!! You're the man

Sent from my Pixel 2 XL using Tapatalk

Sounds like that's the purpose.

 

[dvendt]

The one thing that get's overlooked quite often is the filter settings that were added in a few firmware upgrades from before. Many seem to ignore them or are not familiar of their workings. Their are 2 settings which I found to be very helpful..Global and Site/Department. Global may cure one intermod system issue since it affects all systems, but reduce sensitivity of another. This is where the Site/Department filter setting works much better. I read many posts like these, and I wonder if either settings have been attempted. Yes you can argue that you paid $700 for a scanner and why should I do this, but then if you take this position and your reception suffers, what are you left with?

We have been waiting for a scanner that can decode P25 simulcast systems. Since many public safety departments are switching to these types of systems, it makes sense. Not that analog can be ignored, but more departments are switching.

I live in one of these high RF/intermod areas in a large metropolitan area. Initially some of the reception wasn't as good as I hoped. By taking the time to learn and tweak the filter settings, I can now say it's working better than my 536 which it replaced. Take your time and work with it, you might be pleasantly surprised.

I think some peòple expect these radios to preform like $8000.00 - 10,000.00 Kenwoods and Yaesu's

 

[Hit_Factor]

I think some peòple expect these radios to preform like $8000.00 - 10,000.00 Kenwoods and Yaesu's

Those have lots of filters and settings. The SDS line pales in comparision.

These SDS are so much more capable (any preceding scanner), for best results they have to be operated, not simply turned on.

 

[dvendt]

Those have lots of filters and settings. The SDS line pales in comparision.
These SDS are so much more capable (any preceding scanner), for best results they have to be operated, not simply turned on.

And you pay dearly for all those filters. I wish Uniden had better QC but I wouldn't spend a grand on a scanner. There has to be a compromise somewhere.