I live in the Chicagoland area and scan with SDS-100. It does a fantastic job with picking up P25 I and II transmissions. I can hear simulcasts farther away than I thought I could. Analog is ok, not great, and so is WX. DMR reception, however, is non-existent. I have programmed about 3 DMR systems that are within 5-10 miles of my home, and I still can't hear anything. CAP+ and Data flashes on the display, and signal strength meter shows there is a good signal, but nothing is audible. Every once in a while a transmission is audible, but it comes and goes into the ether and there is no rhyme or reason why this happens. Another thing that I noticed is that I can pick up O'Hare airport operations DMR transmissions, but only if I'm literally sitting at the airport. I use the Sentinel software for programming and I update the database regularly. I have done all troubleshooting that I could image, starting with replacing the antenna, using all filter settings, and just about everything else I was able to find online. I am at a loss and hope someone can chime in.
SDS100/SDS200: SDS100 issues
- Thread starter kbk777
- Start date
Ubbe
Member
Signal strength are not good indicator as it could show the strength of signals several MHz away. Configure one field in the display to show data error. If it shows 5 or higher then it's a bad signal.
/Ubbe
Hi Ubbe, I configured the D-Error setting as you stated, and those numbers are very high. Bad signals indeed. Thank you for the advice! At least now I know that there is some major interference in my surrounding area which is causing DMR on UHF and 900 MHz to receive poorly.
Ubbe
Member
As you have high signal level but bad reception it indicates that you are interfered from another transmitter. Play around with filter settings and IFX to try and get those data errors as low as possible. If the signal are strong enough you can enable the attenuator to that system as reducing the input signal will help a lot to the receiver to overcome interference.
/Ubbe
Ubbe, I researched how to properly set IFX, but just cannot seem to figure out if I did it correctly. Would you mind giving me the quick steps to get there? Thanks!
Ubbe
Member
You will need to stop scan to enable IFX to a frequency. IFX are global so if you program it to one frequency then it will be used wherever that frequency are used in the scanner.
So easiest are to enter the frequency to the display, Channel+freq+Channel and then do Fn+7 to toggle IFX on and off and then continue scan again. You do that to the frequency you suspect are interfered, control channel are one of the voice channels. There's a lot of internal mixing signals in the receiver that produce images and doing IFX will change those images to appear at other frequencies.
SDS100.mp4
drive.google.com
/Ubbe
I found the frequencies that I believe are generating the interference and set IFX as needed. Unfortunately, that did not help. I have also tried various settings such as digital wait time and global/normal/auto filtering but that does not make a difference. I will post a video of my findings/setup shortly.
Since we're both from Chicago, what are you trying to listen to? Might be able to decipher if it's programming issue?
Which DMR system at O'Hare are you trying to hear? If it's a Cap+ (shows MotoTRBO in the database), it has to be programmed as such.
Which DMR system at O'Hare are you trying to hear? If it's a Cap+ (shows MotoTRBO in the database), it has to be programmed as such.
ka3jjz
Wiki Admin Emeritus
In addition did you allocate the right service types?
If the system is in the database, the color codes and other data is kinda shoe-horned into the database. This wiki page describes where to look for that information
wiki.radioreference.com
Mike
If the system is in the database, the color codes and other data is kinda shoe-horned into the database. This wiki page describes where to look for that information
DMR and MOTOTRBO Tips for the BCDx36HP and SDS Scanners - The RadioReference Wiki
Mike
In addition did you allocate the right service types?
If the system is in the database, the color codes and other data is kinda shoe-horned into the database. This wiki page describes where to look for that information
DMR and MOTOTRBO Tips for the BCDx36HP and SDS Scanners - The RadioReference Wiki
Mike
Depending on which system he's trying to listen to, O'Hare's businesses are short ranged. If it's anything other than CPD and CFD, everything else is using the TETRA system.
ka3jjz
Wiki Admin Emeritus
Yeah the low power on airport systems and the antenna are pretty much designed to cover the airport and that's it. Even 5 miles might just be too far away
Mike
Mike
Below are the five systems that I have been working with:
Horizon Therepeutics - 3 miles away
NorthShore University HealthSystem - all four hospitals are 5-10 miles away
Advocate Lutheran General Hospital - 8 miles away
ARINC - O-Hare International Airport - Chicago (DMR 407) - 15 miles away
Northwestern University (P25) - Not part of SC21 - 15 miles away
I understand that most DMR systems are short-range, and I have checked their effective radius. But my SDS-100 does pull them in, but very sparsely. I use Sentinel for most of my programming, specifically when setting up Favorites. Below are my current scanner settings, but I have tried all other combinations as well.
Location: My location with a 30-mile range (no location control)
Service Types - All
Attenuator - Off
Filter - Global
Digital Waiting Time - 400 ms
Horizon Therepeutics - 3 miles away
NorthShore University HealthSystem - all four hospitals are 5-10 miles away
Advocate Lutheran General Hospital - 8 miles away
ARINC - O-Hare International Airport - Chicago (DMR 407) - 15 miles away
Northwestern University (P25) - Not part of SC21 - 15 miles away
I understand that most DMR systems are short-range, and I have checked their effective radius. But my SDS-100 does pull them in, but very sparsely. I use Sentinel for most of my programming, specifically when setting up Favorites. Below are my current scanner settings, but I have tried all other combinations as well.
Location: My location with a 30-mile range (no location control)
Service Types - All
Attenuator - Off
Filter - Global
Digital Waiting Time - 400 ms
Your approximate location?
Lake Cook Rd and Route 43
You're pushing it a bit with those ranges and the systems you're trying to monitor unfortunately. Did you program them as Cap+, with proper LCN's etc.? Using an outdoor antenna by any chance? O'Hare you can cross off the list, you'll have to be very close for all the systems there. The hospitals you'll also be very close, unless you have an outdoor antenna, and might have better luck.
The only hospital site that you might have a shot at is Highland Park Hospital:
Endeavor Health Site: Highland Park Hospital
Endeavor Health Site: Highland Park Hospital Details
www.radioreference.com
Last edited:
Let's take the closest system to my location: https://www.radioreference.com/db/site/37969; Horizon Therepeutics is a DMR Motorola Capacity Plus Single Site (TRBO) system and shows CAP+ . It has two LCNs: 462.05000 (1) and 453.012500 (2) and only three channels. I don't do anything special when adding this system to its own favorite. I do not have an outdoor antenna, just using an upgraded one on the unit instead. This antenna actually does give me better reception than the stock.
Ok...let's do that. Scan only that favorite list that this system is in. I assume you're appending this system?
I looked at it, all the information appears to be good...Color Code/LCN's/Talkgroups. Can you provide a video of what you're seeing?
Horizon Therapeutics Site: Horizon Therepeutics
Horizon Therapeutics Site: Horizon Therepeutics Details
www.radioreference.com
It won't let me post a video here.
Which antenna are you using?
Similar threads
BCD436HP/BCD536HP:
'Unscannable' trunked system or just me? Shift DMR Australia
BCD436HP/BCD536HP:
BCD436HP p25 Phase 2 issues
