Test for P25 Decode Improvement

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UPMan

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Rather than try to post these details in several threads, I'm making one post and hoping you'll see it (and maybe post in the thread you were previously active in pointing here). We've been investigating the various reports of degraded P25 performance in some areas and noted with interest when reports surfaced that changing from NFM to FM mode improved P25 decode performance. We have tentatively verified this, but would like some more confirmation if you don't mind. Here is a relatively easy way to check:

First do MENU --> SETTINGS --> BAND DEFAULTS
Then, scroll to the setting(s) that have the frequency just below the range your local system is using. For example, if you are monitoring an 800 MHz system, scroll to the line that looks like:
849.0:NFM/ 12.5 MHz
Press E and scroll to change NFM to FM.
Press E two more times.
Then, check to see if there was any performance improvement.

For conventional P25, you'll still need to set MOD for the individual channels.

Based on the feedback we get from this, we'll be able to make adjustments that should reflect optimum settings w/o you having to tweak around with these settings.

Oh, and if your P25 decode is just fine, please do the above and see if it degrades your decode performance. We don't want to issue an update that fixes half of you but breaks the other half. :p

To submit a report:
FORMAT FOR REPORTING (to make my life a little easier):
Link to the system in RRDB.
Specific site monitored (if known).
Condition before: Excellent / Poor
Condition after: Excellent / Poor

Then, put any additional discussion you want to add.
 
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NYPDAUX

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Apr 14, 2010
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Wichita, KS
Ok results for Wichita Kansas P25 Stage one originally was set to NFM make changes as per your request to FM did not notice any difference in my P 25 decoding single sounded the same as when it was on NFM the original settings of an FM work clear in Wichita. Kansas. P 25 when switched to FM there was no difference in results still crisp and clear thank you if there's any more of these tests please post will be happy to assist

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jrrob8

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Dec 19, 2002
Messages
116
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Roanoke, Va
that did it. STARS control channel is 152.5475 in my area and is working as we speak. I had already set the band defaults to 7.5 mhz in an atempt to get it working. changed to FM and it is searching id's all over the place. thanks if it keeps on working. I just went to profile and band plan in sentinel and changed the 150.000/161.995 plan to FM and 7.50 which makes mine work perfect. hope it keeps working!

THANKS UPMAN YOU MADE MY DAY


Rather than try to post these details in several threads, I'm making one post and hoping you'll see it (and maybe post in the thread you were previously active in pointing here). We've been investigating the various reports of degraded P25 performance in some areas and noted with interest when reports surfaced that changing from NFM to FM mode improved P25 decode performance. We have tentatively verified this, but would like some more confirmation if you don't mind. Here is a relatively easy way to check:

First do MENU --> SETTINGS --> BAND DEFAULTS
Then, scroll to the setting(s) that have the frequency just below the range your local system is using. For example, if you are monitoring an 800 MHz system, scroll to the line that looks like:
849.0:NFM/ 12.5 MHz
Press E and scroll to change NFM to FM.
Press E two more times.
Then, check to see if there was any performance improvement.

For conventional P25, you'll still need to set MOD for the individual channels.

Based on the feedback we get from this, we'll be able to make adjustments that should reflect optimum settings w/o you having to tweak around with these settings.

Oh, and if your P25 decode is just fine, please do the above and see if it degrades your decode performance. We don't want to issue an update that fixes half of you but breaks the other half. :p
 
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mikewazowski

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Paul, what about band defaults on other bands?

I don't have any 800MHz systems near me but I do have lots of UHF and VHF.
 

UPMan

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My example was just an example. If your system is in another band, the you'd set it for the band your system uses.

NYPDAUX: You fail to mention whether P25 decode was good or bad. Also, from your other posts it seems you are not using the released firmware. Please update your scanner so that we can get comparable results.
 

mikewazowski

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My example was just an example. If your system is in another band, the you'd set it for the band your system uses.

Sorry, I missed the "for example".

Default Modulation has been changed and I'll let you know if it makes any difference although my P25 decoding was good to begin with.
 

NYPDAUX

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Wichita, KS
My example was just an example. If your system is in another band, the you'd set it for the band your system uses.

NYPDAUX: You fail to mention whether P25 decode was good or bad. Also, from your other posts it seems you are not using the released firmware. Please update your scanner so that we can get comparable results.

Yes you are right I'm still using original firmware because there was no problem with receiving I will be willing to upgrade tell me which firmware upgrade version you would like me to put on my radio I hope it will be working fine after doing so.

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NYPDAUX

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Okay we'll go an upgrade firmware now I will keep my fingers crossed

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UPMan

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Setting to 7.5 is not necessary. This just changes the default frequency step size. NFM vs FM changes bandwidth filtering.


FORMAT FOR REPORTING (to make my life a little easier):
Link to the system in RRDB.
Specific site monitored (if known).
Condition before: Excellent / Poor
Condition after: Excellent / Poor

Then, put any additional discussion you want to add.
 

jrrob8

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Dec 19, 2002
Messages
116
Location
Roanoke, Va
thanks for that info, makes it simpler J. R.
by the way, it is decoding just perfect. keeping up with my 106 everything being equal.

Setting to 7.5 is not necessary. This just changes the default frequency step size. NFM vs FM changes bandwidth filtering.


FORMAT FOR REPORTING (to make my life a little easier):
Link to the system in RRDB.
Specific site monitored (if known).
Condition before: Excellent / Poor
Condition after: Excellent / Poor

Then, put any additional discussion you want to add.
 
Last edited:

NYPDAUX

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Joined
Apr 14, 2010
Messages
139
Location
Wichita, KS
Rather than try to post these details in several threads, I'm making one post and hoping you'll see it (and maybe post in the thread you were previously active in pointing here). We've been investigating the various reports of degraded P25 performance in some areas and noted with interest when reports surfaced that changing from NFM to FM mode improved P25 decode performance. We have tentatively verified this, but would like some more confirmation if you don't mind. Here is a relatively easy way to check:

First do MENU --> SETTINGS --> BAND DEFAULTS
Then, scroll to the setting(s) that have the frequency just below the range your local system is using. For example, if you are monitoring an 800 MHz system, scroll to the line that looks like:
849.0:NFM/ 12.5 MHz
Press E and scroll to change NFM to FM.
Press E two more times.
Then, check to see if there was any performance improvement.

For conventional P25, you'll still need to set MOD for the individual channels.

Based on the feedback we get from this, we'll be able to make adjustments that should reflect optimum settings w/o you having to tweak around with these settings.

Oh, and if your P25 decode is just fine, please do the above and see if it degrades your decode performance. We don't want to issue an update that fixes half of you but breaks the other half. :p

Okay export your request I have updated firmware to 1.0 2.0 7 the latest firmware on Sentinel I have gone back and put the frequency back FM mod as you requested I noticed no difference between FM NFM both are clear and loud in Wichita Kansas P25 stage one I hope this is helpful

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NYPDAUX

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Messages
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Wichita, KS
To make sure I understand what you checked:

Using the current released firmware (1.0.7), the P25 performance was excellent regardless of the NFM/FM setting, correct? And the results in the format I requested would have been:

Sedgwick County (Project 25) Emergency Services Radio System Trunking System, Wichita, Kansas - Scanner Frequencies
Site 1
Before: Excellent
After: Excellent

Yes you are correct it is excellent before with original firmware and also excellent with updated firmware from Sentinel I've checked both NFM an FM all loud and clear in Wichita Kansas thank you

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KE4ZNR

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Folks: If you are going to report back with results please submit
them in the format that UPMan has requested them.


Thanks! :)
Marshall KE4ZNR
 
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signal500

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Florida
BCD536HP/BCD436HP Test for P25 Decode Improvement

Rather than try to post these details in several threads, I'm making one post and hoping you'll see it (and maybe post in the thread you were previously active in pointing here). We've been investigating the various reports of degraded P25 performance in some areas and noted with interest when reports surfaced that changing from NFM to FM mode improved P25 decode performance. We have tentatively verified this, but would like some more confirmation if you don't mind. Here is a relatively easy way to check:

First do MENU --> SETTINGS --> BAND DEFAULTS
Then, scroll to the setting(s) that have the frequency just below the range your local system is using. For example, if you are monitoring an 800 MHz system, scroll to the line that looks like:
849.0:NFM/ 12.5 MHz
Press E and scroll to change NFM to FM.
Press E two more times.
Then, check to see if there was any performance improvement.

For conventional P25, you'll still need to set MOD for the individual channels.

Based on the feedback we get from this, we'll be able to make adjustments that should reflect optimum settings w/o you having to tweak around with these settings.

Oh, and if your P25 decode is just fine, please do the above and see if it degrades your decode performance. We don't want to issue an update that fixes half of you but breaks the other half. :p

To submit a report:
FORMAT FOR REPORTING (to make my life a little easier):
Link to the system in RRDB.
Specific site monitored (if known).
Condition before: Excellent / Poor
Condition after: Excellent / Poor

Then, put any additional discussion you want to add.

Link to the system: https://www.radioreference.com/apps/db/?ctid=332
Specific site monitored: 460.15000/465.15000 KIN947 RM 718 NAC A7 Info Net(Records Check) P25 Law Talk
Condition before: Excellent
Condition after: Excellent

Tested on both the BCD536HP and the BCD436HP
 

Dafe1er

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Jan 20, 2011
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Off in a far away place, far from u.......
Monitoring VA STARS P25 Phase 1 system using the BCD436HP unit: Virginia Statewide Agencies Radio System (STARS) Trunking System, Statewide, Virginia - Scanner Frequencies

Change the 148.0:NFM/ 12.5khz to
148.0:FM/ 12.5khz

Monitoring only the following sites:

Arlington
Dumfries (this is the "primary" site everything comes in from since I believe it is the closet tower to me)
Fairfax
Independent Hill
Mobile Site- Richmond
Richmond
Thornburg

Condition before: Excellent
Condition after: Excellent

Seems to sound the same. Does pick up the conversation at the beginning of a transmission a little better than the HP-1 now. But, about the same as with NFM on. I am using a stock antenna on the 436 and a 23" mini mag mount antenna on the HP-1.

*****************EDIT********************
It is hard to tell from waiting on a transmission and then jumping back and forth changing the settings but it does seem to be a much clearer sound during the transmissions with the change for FM you requested above UPman. Not as "garbled" as with the NFM on. Wish I had a second 436 next to mine to compare.
 
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K2KOH

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BCD536HP/BCD436HP Test for P25 Decode Improvement

I assume this his for straight P25 systems like the Rockland CountyNY system.


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