SDS100/SDS200: Debug Help needed with new Motorola Phase 2 system

[devicelab]

With my SDS-100 this system was working just fine -- but then the last few days, I'm noticing a LSM-type issue. It seems that when the scanner detects voice activity on a TGID, the TGID starts flickering on the display -- on/off -- for multiple times. No audio comes through. This is NOT an encryption issue.

I'm using an external antenna and there should be zero signal issues. The really funny thing is that I have my 996P2 on the same system and it's decoding perfectly.

I tweaked the scanner settings. On P25, I usually use NAC enforcement so I tried disabling that. I don't use filters so I tried various filters. No change.

Another odd point is that it doesn't reproduce 100% of the time. It's probably 60/40 right now. The more I listen the more *some* TGIDs are able to be heard. Still it's very flakey. And like I said, this just started happening.

I tried swapping antennas and also a rubber duck. No change. I tried erasing the scanner and reloading my FLs. No change.

So last step was to take a debug log and post it here.

If someone can analyze this then I'd appreciate it. I know at the very end of the log, the issue was showing up. This log has a mixture of working and not-working so it should be fairly obvious -- I hope.

SYSTEM: Port Of Seattle (P25) Trunking System, Seattle, Washington - Scanner Frequencies
SDS-100 LOG: https://www.dropbox.com/s/x6nhkom9jaskukb/log0020256.zip?raw=1

If you need Pro96com details then I can submit that as well.


Cheers!

 

[Ubbe]

It seems to receive TG's that isn't programmed and are not in the RR database. 61204 and 61205.
Do you have it set to ID Search? Do you have one display field that show digital error count and it doesn't go over 5?

/Ubbe

 

[devicelab]

Yes and yes. ID Search and the DEC does jump up a bit at times. IIRC, the highest was around 43. But usually it's 0 or < 10.

 

[devicelab]

When I get some time I'll look at the spectrum and see if there could be some offending signal stomping over the control channel.

 

[Ubbe]

When I get some time I'll look at the spectrum and see if there could be some offending signal stomping over the control channel.

If the 996 decode it then it's not that problem. You'll have to look some +/-7MHz as the RF automatic gain in SDS100 works independent of filter settings, its detector sits right at the front end, and if a real strong signal starts within 7MHz it will reduce the SDS100 overall sensitivity and if your signal are not strong enough it might disappear completely.

The attenuator sits between antenna and the AGC so if your signal are -75dBm or stronger you might be helped by enabling it, to stop the AGC from getting too much RF.

/Ubbe

 

[devicelab]

Okay I'll try enabling the ATT because there's a lot of signals within 7 megs of the CC. It's a very busy band for this area.

 

[devicelab]

Ubbe, it was a no-change on the ATT option. I left it on for a while and it didn't affect the results. I did look at the spectrum and it's very busy and there are signals stomping on the control channel. I can post a picture of what I'm talking about but there's definitely a lot of RF in the band.

Videos are always telling so here's a video of the issue. You'll see that it actually locked on for a few seconds but then couldn't maintain it.

https://www.dropbox.com/s/f526necksgt5mkb/SDS100-Port.mp4?raw=1

The audio you are hearing in the background is the 996P2. BTW, the 996P2 is also using a discone antenna but it's not mounted nearly as high. Signal strength is full though on the 996P2.

 

[tvengr]

Try using IFX on the site frequencies. That will often solve interference problems.

 

[devicelab]

Try using IFX on the site frequencies. That will often solve interference problems.

This is a trunked system. IFX only works on CONV channels.

 

[jtwalker]

This is a trunked system. IFX only works on CONV channels.

This is incorrect. You still put IFX on for the TRS frequencies.

 

[devicelab]

Okay I figured it out but it changed nothing. FWIW the 996P2 and TRX-1 have no trouble with this trunk. I haven't tried the 325P2 but I suspect it'll work fine.

 

[KevinC]

Okay I figured it out but it changed nothing. FWIW the 996P2 and TRX-1 have no trouble with this trunk. I haven't tried the 325P2 but I suspect it'll work fine.

Care to share?

 

[devicelab]

Care to share?

Share what?

 

[KevinC]

Share what?

The fix.

 

[devicelab]

The fix.

No, there was no fix. I was saying I figured out hiw to enable IFX on a trunked system.

 

[KevinC]

No, there was no fix. I was saying I figured out hiw to enable IFX on a trunked system.

Ok. I understand now.

 

[Ubbe]

That signal level of -40dBm is pretty much the maximum that it can display. It's heavy interfered as you can see you have some 45 in D-error but signal still at full level. If you set the Attenuator for that site, does it go down to -60dBm? If not then you are overloaded with RF and needs even more attenuation.

That 852.3375 frequency are heavily interfered. Enter it by Channel+852.3375+Channel and then Fn+7 for IFX. Then select "To Scan"

/Ubbe

 

[tvengr]

That signal level of -40dBm is pretty much the maximum that it can display.

That could be an indication of the cold solder joint problem. How old is the scanner?

 

[devicelab]

If you set the Attenuator for that site, does it go down to -60dBm?

It drops to -105 to -110 with ATT on.

That 852.3375 frequency are heavily interfered. Enter it by Channel+852.3375+Channel and then Fn+7 for IFX. Then select "To Scan"

Enabled that with and without the ATT on and it didn't affect anything.

 

[devicelab]

That could be an indication of the cold solder joint problem. How old is the scanner?

It's one of the originally units and it was also repaired by Uniden for the cold-solder joint.