SDS150: Uniden's Official SDS150 Tech Discussion

[gcopter1]

Received my 150 yesterday. Transferred my previous 100 profile to this one.
Began to notice squelch tails, long ones, as in the radio is stopped on a talkgroup and nothing but noise.

No P25, LINK or DATA is displayed.
Listening to a trunked 800Mhz system, squelch set to 0.
When this happens, after a little while, scan resumes normally.

Anyone else?

 

[KevinC]

Received my 150 yesterday. Transferred my previous 100 profile to this one.
Began starting to notice squelch tails, long ones, as in the radio is stopped on a talkgroup and nothing but noise.

No P25, LINK or DATA is displayed.
Listening to a trunked 800Mhz system, squelch set to 0.
When this happens, after a little while, scan resumes normally.

Anyone else?

Why is your squelch set to zero? That's open squelch.

 

[jtwalker]

Received my 150 yesterday. Transferred my previous 100 profile to this one.
Began starting to notice squelch tails, long ones, as in the radio is stopped on a talkgroup and nothing but noise.

No P25, LINK or DATA is displayed.
Listening to a trunked 800Mhz system, squelch set to 0.
When this happens, after a little while, scan resumes normally.

Anyone else?

First thought … why is squelch set to 0?

 

[gcopter1]

Why is your squelch set to zero? That's open squelch.

Have always had my squelch set to 0 on P25 800Mhz systems, never had this happen?

Have also found setting the squelch to 0 improves reception of the CC on marginal reception areas.
I'm beginning to think, sensitivity on this model is so enhanced to the point of opening the squelch like this.

The times I have had this happen, I don't hear the CC.

 

[J-Wrock]

Received my 150 yesterday. Transferred my previous 100 profile to this one.
Began to notice squelch tails, long ones, as in the radio is stopped on a talkgroup and nothing but noise.

No P25, LINK or DATA is displayed.
Listening to a trunked 800Mhz system, squelch set to 0.
When this happens, after a little while, scan resumes normally.

Anyone else?

I've always had my squelch set to 2 on my 436, 100, 200 and 150 and never noticed any issues on the 800 MHz P25 system in my area. I'm trying it now with squelch set to 0 and I can't really say I hear a difference. Of course if I switch to a conventional system with the squelch at 0 it will stop on the first frequency and I get noise. Not sure why you are hearing squelch noise on the 150 and not the 100 if all other variables are the same.

 

[I_Am_Infinite]

Curiosity Questions:
From what I've read,

RSSI Discrepancy...

Hey all, figured I'd throw this out here for whatever good it might do. The last two weeks, I finally got the opportunity to utilize my SDS200 mobile in it's fullest glory for the first time while my brother was visiting. It had really just been on my desk prior since up here I don't really...

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SDS100/SDS200: - Uniden sds 100 schematics

Hi all I’m looking for a schematic for my Uniden sds 100

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the SDS100 uses either the Rafael TV R836 or R840 chips to receive.

What chipset/circuitry does the SDS150 use that allows it to perform much better than the SDS100, especially without the need for filters?

Also, the SDS100/SDS200 seemed to have an optimal squelch setting of 2. Has this changed with the SDS150 and if not, does it even need to change, given the performance improvements noted?

Like I said, just curious...

Thanks

I had my squelch at 3 on my systems but just changed from it to 2, to see any difference on my SDS 200, I've not seen a difference really but I agree 2 seems the lowest u can go before breaking squelch. I agree also it Shud be optimal sensitivity at 2.

 

[rr60]

Very possible to set a negative delay in the search setting to avoid hitting the "avoid'.

Thanks,

The negative delay works but one must listen to the data channel for 5 seconds on each and every search pass, this is not workable. For now avoid is fine. One pass and takes a minute or so to delete the 6 or so data channels I see.

Clean: The cleaner approach would be to have FW respond as it now does on systems with the latest FW revision. Ignore P25 data channels.

 

[Ubbe]

Could someone please check how the discovery mode are working. It has been working fine in HP-1 but in later scanners it is broken.
It doesn't skip hits already being "discovered" or already in the database and for the HP-1 it also checks the loaded Favorite lists as well as the the Discovery modes own system log. When it doesn't work it still stops on hits already found.

The SDS150 user manual isn't really clear exactly how it is supposed to work but it says "ignore the hit if already in the database" but for Record Duration it says when the time has been met the hit are considered "discovered" but doesn't say it that then should ignore any more hits or just not log anymore. To me "discovered" would equal already in the database :

Conventional Discovery mode lets you monitor a range of frequencies, log frequencies with activity, and recording the audio for frequencies that are not already known to be in use in your area so that you can more easily identify the users. This includes frequencies used conventionally as well as in trunked radio systems.
In both modes, you also have the option to compare hits to the Database, log all hits, or only log new hits.

Set Logging ALL for all hits; NEW for only items that are not yet discovered in this session

Set Compare to Database
On compares hits to database and ignores the hit if it is already in the database. Off records all hits.

Set Record Duration
Sets how much audio the scanner records for each hit. Once the record duration has been met, the frequency or TGID is considered "discovered.”

/Ubbe

 

[J-Wrock]

Quick question about the SDS 150 battery. I charge my scanner to full charge on the charging cradle. When I turn it on, it shows a battery charge between 4.18 and 4.20 volts. The moment I take it off the cradle, it drops to 4.09. Is this normal?

 

[jasonhouk]

Could someone please check how the discovery mode are working. It has been working fine in HP-1 but in later scanners it is broken.
It doesn't skip hits already being "discovered" or already in the database and for the HP-1 it also checks the loaded Favorite lists as well as the the Discovery modes own system log. When it doesn't work it still stops on hits already found.

The SDS150 user manual isn't really clear exactly how it is supposed to work but it says "ignore the hit if already in the database" but for Record Duration it says when the time has been met the hit are considered "discovered" but doesn't say it that then should ignore any more hits or just not log anymore. To me "discovered" would equal already in the database :

Conventional Discovery mode lets you monitor a range of frequencies, log frequencies with activity, and recording the audio for frequencies that are not already known to be in use in your area so that you can more easily identify the users. This includes frequencies used conventionally as well as in trunked radio systems.
In both modes, you also have the option to compare hits to the Database, log all hits, or only log new hits.

Set Logging ALL for all hits; NEW for only items that are not yet discovered in this session

Set Compare to Database
On compares hits to database and ignores the hit if it is already in the database. Off records all hits.

Set Record Duration
Sets how much audio the scanner records for each hit. Once the record duration has been met, the frequency or TGID is considered "discovered.”

/Ubbe

I’m not 100% sure what you are looking for here. I extensively tested “Discovery mode” while the SDS150 was in beta. The 150 checks the favorites list and site you choose during discovery setup or the full database if you have it active and choose.

For my testing I took TGID’s out of my favorite list that I knew were very active (State correction facilitates)

I ran a short test this morning and the results are in a video here: MARCS MRN DISCOVERY

 

[jasonhouk]

Quick question about the SDS 150 battery. I charge my scanner to full charge on the charging cradle. When I turn it on, it shows a battery charge between 4.18 and 4.20 volts. The moment I take it off the cradle, it drops to 4.09. Is this normal?

This is normal.

 

[CollinsURG]

Quick question about the SDS 150 battery. I charge my scanner to full charge on the charging cradle. When I turn it on, it shows a battery charge between 4.18 and 4.20 volts. The moment I take it off the cradle, it drops to 4.09. Is this normal?

You will see that behavior with any radio that charges the battery when it is installed and you are monitoring battery voltage. The charging voltage rises as the battery's internal resistance becomes less and the voltage will be a bit higher than the battery's voltage is when it is disconnected from the charger.

Same thing happens with the SDS100 or BCD325P2 if you are monitoring the voltage when the USB cable is connected and charging the battery, then unplug the cable. You will see the voltage drop.