TRX-2: Scan Rate Seems Slower Than Older Uniden

Status
Not open for further replies.

kb7ado

Member
Joined
Mar 20, 2005
Messages
7
Anyone set their TRX-2 side by side with their previous scanner for speed comparison? I've noticed my BC796D hits on channels a lot faster than the TRX-2. The BC796D specs say it has a 100 channels per second scan rate. You wouldn't think it would seem that different from 70 channels per second, but the BC796D is noticeably faster at stopping on an active frequency than the TRX-2. Hey Whistler, how about an increase in scan speed the next time you do a firmware update?
 

kb7ado

Member
Joined
Mar 20, 2005
Messages
7
If you mean the delay period, it was only set for 2 seconds, the same as on the Uniden. I had both of them on the same antenna monitoring the same frequencies and the BC796D would always stop on the active channel about 1 second earlier than the TRX-2. The Uniden would catch most of both sides of the conversation between state troopers when scanning whereas the TRX-2 wouldn't. I've since increased the delay period so it will hold longer to catch the reply. It just seems like it shouldn't be so noticeable when you're talking about 70 channels a second versus 100 channels per second, especially if you're only monitoring about 10 channels.
 

Ubbe

Member
Joined
Sep 8, 2006
Messages
3,441
Location
Stockholm, Sweden
If you set the IF Output to headphone you can listen from the headphone jack how scanning sweeps or hesitates over the channels, or connect to a computer or oscilloscope to see and measure whats going on.

/Ubbe
 

byndhlptom

Member
Joined
Nov 1, 2005
Messages
356
Location
JoCo, KS (SoDak native)
Scan speed

kb7ado
"Hey Whistler, how about an increase in scan speed the next time you do a firmware update?"

It not just a change to a couple of lines of code to change speed......

to change a channel on a modern scanner(minimally)....

get channel info from memory
send frequency/bandwidth info to RF section (VFO, IF)
send modulation info to Audio recovery section
wait for RF section to stabilize/settle
Check for channel activity
If active, enable audio (unmute), When signal drops, mute, Check for delay setting(s)
IF not active, go to next channel
repeat

Trunking adds another layer to this......

each of these steps requires a finite time to accomplish, things can not be rushed

usually the manufacturer has already optimized the times because a faster scan is a selling point.......

$.02
 

troymail

Silent Key
Joined
Dec 19, 2002
Messages
9,977
Location
Supply (Lockwood Inlet area), NC
kb7ado
"Hey Whistler, how about an increase in scan speed the next time you do a firmware update?"

It not just a change to a couple of lines of code to change speed......

to change a channel on a modern scanner(minimally)....

get channel info from memory
send frequency/bandwidth info to RF section (VFO, IF)
send modulation info to Audio recovery section
wait for RF section to stabilize/settle
Check for channel activity
If active, enable audio (unmute), When signal drops, mute, Check for delay setting(s)
IF not active, go to next channel
repeat

Trunking adds another layer to this......

each of these steps requires a finite time to accomplish, things can not be rushed

usually the manufacturer has already optimized the times because a faster scan is a selling point.......

$.02
Agree -- scanners are trying to do so much more these days. It takes time to process the wide variety of types.

Back in the day it was just conventional analog.... easy (looking back of course).

Then trunking - Motorola, EDACS, LTR, etc.

Then mixed mode (analog and/or digital on the same frequencies).

Then fully digital systems.

And now even mode different digital modes - P25 Phase1 and Phase 2, DMR, NXDN, not to mention other signals/digital modes that the scanners don't handle (paging, etc.).

The more you try to scan, the variety of those systems, and use of "auto" settings are going to slow things down. In search modes, if makes sense to "auto" detect things. However, as much as is possible, you definitely want to limit the use of "auto" settings for things that are stable and known.

And, as new capabilities get added, you rarely see anything in this processing being "removed" to compensate/make room for new things.

It takes time for the scanner to "prepare" (initialize) for each of those different modes before actually doing it.

Think of it this way: if I know a foreign visitor is coming but you don't tell me what language they'll be speaking when they arrive (or I fail to prepare), it's going to take me alot longer to communicate with them than if you tell me in advance they'll be speaking say - French when they arrive so I can either learn the language in advance or as least have an interpreter on hand to quickly bridge the divide....

EDIT: Thinking about all of this - I wonder if there is a way (in the future?) for the scanner companies to allow users to enable/disable various types to speed things up (i.e. tell the scanner "hey, I'm only going to use you to listen to NXDN", etc.... If it would significantly increase the scan/processing speed perhaps there is a chance they would. However, there would probably have to be a large audience/call for that kind of feature (which is unlikely since everybody tends to want everything all the time).
 
Last edited:

sibbley

Member
Premium Subscriber
Joined
Feb 18, 2013
Messages
1,467
Location
Nazareth, Pennsylvania
Exactly why my "digital" scanners only scan digital modes.

436 does only DMR and P25 Phase 2. 536 only does DMR search.
396xt only P25 Phase 1.
TRX-1 and TRX-2 only do NXDN.
PSR-800, DMR - Why? Because now it can!
 

buddrousa

Member
Premium Subscriber
Joined
Jan 5, 2003
Messages
6,113
Location
NW Tenn
Sibbley that is why I have 10 scanners on my desk #1 BCT15 Analog Police, #2 BCT15X Analog Trunking,#3 BCT15X Analog EMS, #4 785D Backup, #5 996P2 District 4 THP,#6 996P2 Distric 8 THP, #7 BCD536HP DMR, #8 BCD536HP P25 MOWINS, #9 TRX-2 NXDN, and #10 PRO-197 logging P25 TACN UID's with PROCOM96.
 

sibbley

Member
Premium Subscriber
Joined
Feb 18, 2013
Messages
1,467
Location
Nazareth, Pennsylvania
Yes sir, the more you try to scan with one radio or scanner, the more you miss transmissions.

I have a Pro-107 that just scans 4 LTR systems, 125AT that just scans my county's public safety, 396xt just for a single EDACS system, TK-290 for a neighboring county's VHF public safety system, TK-390 for another neighboring county's UHF public safety system, VX-454 that scans my county's fire tac channels, HT1250 that scans my county's PD channels, VX-539 that scans local college public safety and a few other DMR public safety users, CS700 and CS750 that scan HAM and business users I like to listen to, an MD-380 I use to scan a few other businesses, DJ-X11t for finding new analog, a 996xt I use for just a few P25 conventional frequencies, and a few other older scanners and radios to use for whatever I feel like doing at the time. I also have a Unication G1 to alert me when my local fire and EMS go out, I just bought a G4 to use exclusively for a select few channels on a local city's Phase 1 system, and last week I bought a CS760. I also have 2 RTL SDR dongles running on DSD+ to search for DMR and NXDN.

Most people think I'm crazy!
 

buddrousa

Member
Premium Subscriber
Joined
Jan 5, 2003
Messages
6,113
Location
NW Tenn
Well do have a picture of Wiley Coyote for your avatar. He was known for trying hard but not having much luck. In the process of getting a NX5300 ANALOG, NXDN, and DMR to add to my other HT's
 

Ed6698

Member
Joined
Feb 19, 2011
Messages
1,182
Location
Lake County Indiana
One of the reasons I bought a 1095, I mainly monitor 2 P25 systems, both fairly large. I dedicate the 1095 to my local county system, my 1080 to state system. I could put them both on 1 scanner, but both systems can get pretty active at times. If I only had 1 scanner I would miss stuff for sure, no matter the scan rate, actually could almost use a 3rd.
 

Circa

Member
Joined
May 20, 2014
Messages
180
Location
Ohio
If you mean the delay period, it was only set for 2 seconds, the same as on the Uniden. I had both of them on the same antenna monitoring the same frequencies and the BC796D would always stop on the active channel about 1 second earlier than the TRX-2. The Uniden would catch most of both sides of the conversation between state troopers when scanning whereas the TRX-2 wouldn't. I've since increased the delay period so it will hold longer to catch the reply. It just seems like it shouldn't be so noticeable when you're talking about 70 channels a second versus 100 channels per second, especially if you're only monitoring about 10 channels.
My Pro-668 and WS1080 also do this.
My unidens and tyt/Baofeng transceivers all catch more of the beginning.
I have a retro uniden base that also opens faster.
Same thing happens when paused.
2-way Motorola handhelds they're using also open up faster.
I'm going to be following this thread. When I posted mine, I didn't solve it.
Only thing people recommended was playing with the search for tones setting. Like maybe if the scanner has the pll tone, maybe it will open quicker.
If you set the IF Output to headphone you can listen from the headphone jack how scanning sweeps or hesitates over the channels, or connect to a computer or oscilloscope to see and measure whats going on.

/Ubbe
Could you elaborate more on doing this? (minus the oscilloscope part unless I can find a program that does it over a mic jack)
I would like to try.

Sent from my Nexus using Tapatalk
 
Last edited:

nosoup4u

Member
Premium Subscriber
Joined
Jan 30, 2002
Messages
1,914
Location
High Bridge, NJ
While we are on a subject on scan speed, maybe someone can answer this question.

Say I have 1 trunk system and the talkgroups are split between 2 scan lists. If I have both scan lists enabled, does it scan the trunk system once and looks for all the talkgroups, or does it scan the system twice, once for each set in each scan list?
 

troymail

Silent Key
Joined
Dec 19, 2002
Messages
9,977
Location
Supply (Lockwood Inlet area), NC
While we are on a subject on scan speed, maybe someone can answer this question.

Say I have 1 trunk system and the talkgroups are split between 2 scan lists. If I have both scan lists enabled, does it scan the trunk system once and looks for all the talkgroups,
Yes.

or does it scan the system twice, once for each set in each scan list?
No.

As I understand it, you only have 1 copy of the system programmed and all of the talkgroups are on the same system. Therefore, the scanlist separation is simply a "logical" separation of talkgroups scanned on a single system.

That is, the system is only being scanned once (unless you've used the "duplicate" button to create a 2nd copy of the system or have somehow created a 2nd copy of the system another way).
 

Ubbe

Member
Joined
Sep 8, 2006
Messages
3,441
Location
Stockholm, Sweden
Could you elaborate more on doing this? (minus the oscilloscope part unless I can find a program that does it over a mic jack) I would like to try.
In the program menu/global settings expert, or in EZScan advanced features, you can set IF out to HP/headphone. Then you will be listening to the unsquelched audio from the headphone jack which is what the scanner is trying to decode.

If I remember correctly the mp3 player Winamp had an oscilloscope mode but it was probably some other program where one could freeze the screen and measure the milliseconds between each spike in the audio that indicated a frequency change.

/Ubbe
 

TailGunner61

Member
Premium Subscriber
Joined
Dec 6, 2009
Messages
15
Location
Elko, NV
All of the technical info is understood (what the scanner has to do for each frequency or object). But why does my WS-1040 and my RS Pro-164 scan the exact same channels/objects (mixture of conv & trunked) so much faster than the more expensive TRX-2? The TRX-2 misses a lot of communications because of its slow speed. Unless this expensive scanner (TRX-2) can scan at least as fast as the less expensive ones I have, I'm really disappointed in the TRX-2. Can anyone tell me how to get the same (or better) level of service w/ the TRX-2?
 
Last edited:

troymail

Silent Key
Joined
Dec 19, 2002
Messages
9,977
Location
Supply (Lockwood Inlet area), NC
It might depend on what you have programmed and other settings such as squelch. Keep in mind that the TRX models are trying to handle alot more than the older (WS1040) models. The TRX adds DMR and NXDN.

A bad squelch setting can greatly reduce the scan rate - I think the default is 10 which is where I tend to keep that setting but there is a knob so there is nothing saying 10 is right for all situations.

What do you have programmed and how did you program it?
 

TailGunner61

Member
Premium Subscriber
Joined
Dec 6, 2009
Messages
15
Location
Elko, NV
My squelch level is set at ten. I imported the objects directly from my WS-1040 to the EZ-Scan software and then into my TRX-2. The same objects are selected and the same lockouts are there (for objects I don't want to scan). The objects are a mixture of conventional freqs and EDACS trunking talk groups. The entries are identical but the TRX is so slow it misses a lot of transmissions.
 

troymail

Silent Key
Joined
Dec 19, 2002
Messages
9,977
Location
Supply (Lockwood Inlet area), NC
What method is being used to calculate the scan rate?

Also - I assume you used the File->Import from WS1040/WS-1065 option -- I haven't really used that much if at all ... any chance something is being incorrectly imported/converted with that option?

Just looking at possibilities....
 

buddrousa

Member
Premium Subscriber
Joined
Jan 5, 2003
Messages
6,113
Location
NW Tenn
My squelch level is set at ten. I imported the objects directly from my WS-1040 to the EZ-Scan software and then into my TRX-2. The same objects are selected and the same lockouts are there (for objects I don't want to scan). The objects are a mixture of conventional freqs and EDACS trunking talk groups. The entries are identical but the TRX is so slow it misses a lot of transmissions.
So from what you are saying is you bought a TRX-2 just to scan ANALOG FREQUENCIES?
If you are scanning Trunking Systems then the dwell times are going to be longer looking for Digital Systems.
If you are scanning Conventional Frequencies then the dwell times are going to be longer looking for Digital Information.
 
Status
Not open for further replies.
Top