Hello, my 12.5 kHz repeater system has a long noise tail compared to my 20 kHz repeater system. Both use the USB URI with flat audio and carrier from dsp in carrier squelch mode. Moreover the rxnoise tuning comes with a warning: db0fox*CLI> radio tune rxnoise tune rxnoise maxtries=12, target=27000, tolerance=2750 tries=0, setting=2, meas=15368 tries=1, setting=4, meas=21645 tries=2, setting=5, meas=26274 tries=3, setting=5, meas=25744 tries=4, setting=5, meas=26047 tries=5, setting=5, meas=26010 tries=6, setting=5, meas=26393 DONE tries=6, setting=312, meas=26393, sqnoise=5990 INFO: RX INPUT ADJUST SUCCESS. WARNING: Insufficient high frequency noise from receiver. WARNING: Rx input point may be de-emphasized and not flat. usbradio.conf setting of 'carrierfrom=dsp' not recommended. New repeater systems in germany are now limited to 12.5 kHz. Would be nice to build them with the Asterisk/app_rpt system. Are there any plans to adjust the code for 12.5 kHz systems? I'll have a talk about the Asterisk/app_rpt system in two weeks at a conference in germany. Tnx, 73, Jann -- Jann Traschewski, Drosselstr.1, D-90513 Zirndorf, Germany Tel.: +49-911-696971, Mobile: +49-170-1045937, E-Mail: jann@gmx.de Ham: DG8NGN / DB0VOX, http://www.qsl.net/dg8ngn, ICQ UIN: 4130182
One of the other distros for getting app_rpt running supports a narrowband toggle function. It is from www.xelatec.com/. They have a "switch" in the sw that toggles something in the dsp for 12k5 use. I played with it as our 900 mhz band is mostly 12k5 equipment these days... It did work.. However.. in general The audio pickup point in the discriminator chain has more to do with getting enough white noise I think.. I had to play around some in the 900 gear but found points suitable for either distro.. Doug KD8B -----Original Message----- From: app_rpt-users-bounces@qrvc.com [mailto:app_rpt-users-bounces@qrvc.com] On Behalf Of Jann Traschewski Sent: Thursday, March 11, 2010 7:51 AM To: 'app_rpt mailing list' Subject: [App_rpt-users] 12.5 kHz repeaters support Hello, my 12.5 kHz repeater system has a long noise tail compared to my 20 kHz repeater system. Both use the USB URI with flat audio and carrier from dsp in carrier squelch mode. Moreover the rxnoise tuning comes with a warning: db0fox*CLI> radio tune rxnoise tune rxnoise maxtries=12, target=27000, tolerance=2750 tries=0, setting=2, meas=15368 tries=1, setting=4, meas=21645 tries=2, setting=5, meas=26274 tries=3, setting=5, meas=25744 tries=4, setting=5, meas=26047 tries=5, setting=5, meas=26010 tries=6, setting=5, meas=26393 DONE tries=6, setting=312, meas=26393, sqnoise=5990 INFO: RX INPUT ADJUST SUCCESS. WARNING: Insufficient high frequency noise from receiver. WARNING: Rx input point may be de-emphasized and not flat. usbradio.conf setting of 'carrierfrom=dsp' not recommended. New repeater systems in germany are now limited to 12.5 kHz. Would be nice to build them with the Asterisk/app_rpt system. Are there any plans to adjust the code for 12.5 kHz systems? I'll have a talk about the Asterisk/app_rpt system in two weeks at a conference in germany. Tnx, 73, Jann -- Jann Traschewski, Drosselstr.1, D-90513 Zirndorf, Germany Tel.: +49-911-696971, Mobile: +49-170-1045937, E-Mail: jann@gmx.de Ham: DG8NGN / DB0VOX, http://www.qsl.net/dg8ngn, ICQ UIN: 4130182 _______________________________________________ App_rpt-users mailing list App_rpt-users@qrvc.com http://qrvc.com/mailman/listinfo/app_rpt-users
Hi,
mhz band is mostly 12k5 equipment these days... It did work.. However.. in general The audio pickup point in the discriminator chain has more to do with getting enough white noise I think.. I had to play around some in the 900 gear but found points suitable for either distro..
Please note that this is a commercial grade radio, no searching for a discriminator tap, but using the flat out that is provided by the manufacturer. Those radios should remain exchangable without modifying them, so this is not really an option :-) I will definetely not start soldering thin wires into my repeater radios, as I rely on direct replacement with a brand new radio in case of failure.
Doug KD8B
With best regards Ralph.
I do understand, however because it has a commercial flat audio point does not mean it has the appropriate noise component for the software to detect . The manufacturer does not necessarily allow much white noise content on a flat audio line... as flat audio by definition is not discriminator as a discriminator is not flat unless the received signal is flat and normally it is pre-emphasized... So to be flat it is processed.. and white noise may be stripped. The white noise we are talking about is in the audio band above 3khz.. up to maybe 6-7 khz.. you might sweep your receiver there for flat audio and watch that with a scope.. flat in band audio does not mean flat to 6khz... If the chosen radios do not have sufficient white noise the only real option is to add COR or CAS detection... as I do not think it is a wideband narrowband issue you are seeing.. The way to test that is see if the same radios align suitably in wideband mode assuming they can be programmed to test... If the URI cannot find an answer there.. it is most likely just a bad spot to pick noise from... What I will also add is the level output is different on many radios ( especially in 12k5) and in my case I had to play with external padding as well as the 20db gain/pad switch to get levels into a range the rx tuning software and hardware could deal with... The internal resistors of the URI are designed for a certain working range and load.. In most wideband and narrowband installs where I use the URI ( 6 installations I am involved in) , I had to go to the capacitive-ly coupled input as DC component on the rx line had adverse effects on the URI's ability to function and calibrate. Doug KD8B -----Original Message----- From: Ralph A. Schmid, dk5ras [mailto:ralph@radio-link.net] Sent: Thursday, March 11, 2010 8:22 AM To: Doug Bade; 'Jann Traschewski'; 'app_rpt mailing list' Subject: RE: [App_rpt-users] 12.5 kHz repeaters support Hi,
mhz band is mostly 12k5 equipment these days... It did work.. However.. in general The audio pickup point in the discriminator chain has more to do with getting enough white noise I think.. I had to play around some in the 900 gear but found points suitable for either distro..
Please note that this is a commercial grade radio, no searching for a discriminator tap, but using the flat out that is provided by the manufacturer. Those radios should remain exchangable without modifying them, so this is not really an option :-) I will definetely not start soldering thin wires into my repeater radios, as I rely on direct replacement with a brand new radio in case of failure.
Doug KD8B
With best regards Ralph.
I do understand, however because it has a commercial flat audio point does not mean it has the appropriate noise component for the software to detect .
It has, when switched to 25 KHz, but the filtering of course also narrows audo bandwidth.
The white noise we are talking about is in the audio band above 3khz.. up to maybe 6-7 khz.. you might sweep your receiver there for flat audio and watch that with a scope.. flat in band audio does not mean flat to 6khz...
6 KHz is to much fur 12.5 KHz, of course.
The way to test that is see if the same radios align suitably in wideband mode assuming they can be programmed to test... If the URI cannot find an answer there.. it is most likely just a bad spot to pick noise from...
Like Jann already had mentioned, in wide band it is just fine. There can not be very much additional filtering, as I can pass P25 and D-Star through this output. This leads to a topic that I at least dropped here for two times, but with no response. I would like to route the flat audio from DC level up to some KHz through the PC, to allow P25 and D-Star through it. No codec, no DSP processing (maybe even regenerating the digital signals in a later version), no filtering. No LP, no HP. Nothing. Is there a possibility to enable this? Maybe even to route this over the internet, to allow linking of multi mode repeaters? It would be a great feature to have all the asterisk features, all the tone decoding stuff, DSP squelch - but without touching the audio.
What I will also add is the level output is different on many radios ( especially in 12k5) and in my case I had to play with external padding as well as the 20db gain/pad switch to get levels into a range the rx tuning software and hardware could deal with... The internal resistors of the URI are designed for a certain working range and load..
AFAIR the Motorolas are around 400 or 500 mV, but I am not sure.
Doug KD8B
With best regards Ralph.
participants (3)
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Doug Bade -
Jann Traschewski -
Ralph A. Schmid, dk5ras