Filter Bandwidth

[millam]

Is there a way to keep FMPA from changing the filter bandwidth. I want to keep the bandwidth at 7.6
continuously. I have a nexedge96 system that FMPA thinks is TDMA when filter bandwidth is above 7.6.
When FMPA switches to TDMA DSDPlus loses sync till it finds the CC again, over and over. -b-7.6 I guess
works in FMP24, have not tired that, think I will. Any troubleshooting ideas?

Mil

 

[millam]

FMP24 works at all filter bandwidths. FMPA works correctly on nexedge48 systems, but I
will check that. I only have 1 nexedge96 system I can hear.

Mil

 

[dave3825]

-b-7.6 I guess
works in FMP24, have not tired that, think I will.

For 7.6, it would be -b7.6, not -b-7.6

I don't have any Nexedge96 so all I can offer is what's listed in the FMP24 and FMPA.scanlist files. The tuner may default to what's shown below regardless of what switch is in your bat.. I seem to remember something from a while ago.

; Options:
;
; Modulation Specifier
;
; 4 kHz bandwidth digital protocol specifiers:
;
; iDAS
; NX48
; NXDN48
; NEXEDGE48
;
; 7.6 kHz bandwidth digital protocol specifiers:
;
; Dstar
; D-Star
; DMR
; TRBO
; Cap+
; Con+
; TIII
; XPT
;
; 9.5 kHz bandwidth digital protocol specifiers:
;
; Fusion
; NX96
; NXDN96
; NEXEDGE96
; P25
;
; 12.5 kHz bandwidth digital protocol specifiers:
;
; PV
; ProVoice
;
; Analog modulation specifiers:
;
; Anything else, such as "FM" or "Analog" or nothing
; is assumed to be FM modulated analog and defaults to 12.5 kHz bandwidth
;
;

 

[millam]

For 7.6, it would be -b7.6, not -b-7.6

I don't have any Nexedge96 so all I can offer is what's listed in the FMP24 and FMPA.scanlist files. The tuner may default to what's shown below regardless of what switch is in your bat.. I seem to remember something from a while ago.

Yea Dave -b-7.6 works for FMP24 but is illegal for FMPA. I was hoping someone had a work around for FMPA. Guess I'll have
to dig out another rtl sdr and go with FMP24 for this system.

Mil

 

[dave3825]

-b-7.6 works for FMP24 but is illegal for FMPA. I was hoping someone had a work around for FMPA.

And I guess this is a misprint in FMP24 help as it does not list a 7.6 as an option..
FMP24 Help says -b<kHz> Initial RF filter bandwidth (4, 7, 9.5, 12.5, 22) [-b7]

Anyway, I just looked at my fmp24 bat file that specifies -b12.5 and when it lands on a P25 Phase 2 cc, it defaults to 9.5.
Changing the switch to -b-12.5 overrides and keeps it on 12.5 on both cc and voice freqs.

On my airspy bat, -b12.5, when its on the cc it defaults to 9.5. When on a voice call, it switches to 12.5

Maybe email DSDPlus?

 

[millam]

Saw that Dave but nowhere else was 7 an option but 7.6 was. Probably missed it. Right
now on a single sdr it is staying put at 7.6 using -b-7.6 on the system in question. Has
anyone had DSDPlus respond to an email in the last year?

Mil

 

[dave3825]

I reported an issue related to using Fmp24.scanist on 7/29 and they responded 8/2.

 

[millam]

I reported an issue related to using Fmp24.scanist on 7/29 and they responded 8/2.

Gotcha, kinda thought they had went awol. Good to know they are still active. They have a good product.
Can't remember if am a life time subscriber or not, may just send them some money for thanks.

Mil

 

[CanesFan95]

I've always wished they would make FMPA let you tell it the bandwidth. This is a long-time known defect/flaw.

 

[millam]

I've always wished they would make FMPA let you tell it the bandwidth. This is a long-time known defect/flaw.

Thanks, I am glad its not me. If another nexedge96 system starts up near me I will see if its doing the same. Dug out
another rtl-sdr and edited by bat file to use FMP24 instead of FMPA for this system. Thanks yall;

Mil

 

[R0am3r]

On my airspy bat, -b12.5, when its on the cc it defaults to 9.5. When on a voice call, it switches to 12.5

I see this same behavior on my SDRplay RSP1A. When I start FMPP.exe with a specified bandwidth (e.g. -b7.6), it remains at that bandwidth until I start DSDPlus.exe. If DSDPlus.exe recognizes a P25 Phase 2 CC, it switches FMPP to the proper bandwidth of 9.5. When the tuner switches to a voice channel, the bandwidth jumps to 12.5 for that call.

I tested this behavior on a local NEXEDGE96 system. As expected, FMPP switched to a bandwidth of 9.5 for both the CC and the voice channels. The NEXEDGE96 system I am monitoring keeps the CC and switches to/from the voice channels properly.

IMHO - I like the intelligence the DSDPlus FL authors put into the software.

 

[millam]

I see this same behavior on my SDRplay RSP1A. When I start FMPP.exe with a specified bandwidth (e.g. -b7.6), it remains at that bandwidth until I start DSDPlus.exe. If DSDPlus.exe recognizes a P25 Phase 2 CC, it switches FMPP to the proper bandwidth of 9.5. When the tuner switches to a voice channel, the bandwidth jumps to 12.5 for that call.

I tested this behavior on a local NEXEDGE96 system. As expected, FMPP switched to a bandwidth of 9.5 for both the CC and the voice channels. The NEXEDGE96 system I am monitoring keeps the CC and switches to/from the voice channels properly.

IMHO - I like the intelligence the DSDPlus FL authors put into the software.

Yea I had no problem with it till this site started to decode as TDMA when using FMPA. Strange today I can't make
it decode TDMA. The only problem with DSDPlus setting filter bandwidth is that I have 2 sites that have very close
transmitters next to them, lots of errors unless I set the filter bandwidth lower. Ah nothing is perfect, just live with, HUH.

Mil

 

[millam]

Update: the nexedge96 site goes into TDMA decoding when the signal is above a certain level (?).
I can lower the gain until it quits TDMA and returns a normal signal. I had rotated my antenna 180
looking for another site and it worked, signal was weaker. It only happens on nexedge96 signals and
FMPA.exe program. I can live with this. Thanks for the inputs, bye.

Mil

 

[mtindor]

Update: the nexedge96 site goes into TDMA decoding when the signal is above a certain level (?).
I can lower the gain until it quits TDMA and returns a normal signal. I had rotated my antenna 180
looking for another site and it worked, signal was weaker. It only happens on nexedge96 signals and
FMPA.exe program. I can live with this. Thanks for the inputs, bye.

Mil

@millam Is this the thread you were talking about where you have problems with FMPA? If so, It would be very useful if you would record raw audio at a time when the NXDN site is busy, you are using FMPA/DSDPlus to monitor it, and you are experiencing the "TDMA" issue. If you capture a few minutes of raw audio, zip it up, and either upload it to a free upload site and link to it here, or send it to dsdplusfastlane@gmail.com, that might be helpful. Better to upload it somewhere and link to it here so that many people can take a look. And you would want to post the specific site you are monitoring and maybe a few of the multiple strong signals in close proximity via the FMPA waterfall -- just a screenshot.

 

[millam]

@millam Is this the thread you were talking about where you have problems with FMPA? If so, It would be very useful if you would record raw audio at a time when the NXDN site is busy, you are using FMPA/DSDPlus to monitor it, and you are experiencing the "TDMA" issue. If you capture a few minutes of raw audio, zip it up, and either upload it to a free upload site and link to it here, or send it to dsdplusfastlane@gmail.com, that might be helpful. Better to upload it somewhere and link to it here so that many people can take a look. And you would want to post the specific site you are monitoring and maybe a few of the multiple strong signals in close proximity via the FMPA waterfall -- just a screenshot.

Yea it is, got the site going with fmp24 and kinda forgot it. I'll figure out how to save an audio file and where to save it
and get it to dsdplus people. Just thought if I could prove it was a FMPA problem they might listen to me.

Mil

 

[mtindor]

Yea it is, got the site going with fmp24 and kinda forgot it. I'll figure out how to save an audio file and where to save it
and get it to dsdplus people. Just thought if I could prove it was a FMPA problem they might listen to me.

Mil

They'll listen to you. They just have to have the right information to check into it. In this case it's going to be raw audio.

Assuming you are running the latest version of DSDPlus, once you set things back up to use FMPA/DSDPlus instead of FMP24/DSDPlus, navigate to the problematic system/site. Then click on the INPUT menu and select "Start Source Audio recording". Let it monitor for a few minutes. Then click on the INPUT menu and select "Stop Source Audio recording". In the Event Log window it will tell you the name of the raw audio file that you just recorded, which it would have just written to your DSDSPlus folder. Zip that up and send it to dsdplusfastlane@gmail.com with an explanation of what is going on. Of course, honestly it would be better if you were to upload it to some free upload site where you can then put a link here in the forum so that not only can the author reference it and perhaps help you out, but others here on the forum can as well. Easyupload.io is just one site you could use to upload the zip'd file and then grab a link to post here.

 

[millam]

Seems that the DSD team saw my email to them. This problem seems to be fixed in 2.465. Thanks
guys / guy / gals / gal / person / you. Unsure how to communicate these days. LOL!

Mil