Narrowbanding with Quantar poor audio
Posted: Wed Aug 09, 2017 7:00 am
Hello all,
Have been cleaning up a guys work here in the county that left and found that he left all the county's Quantar stations set to 4k deviation not 2.5. I have 3 systems that use the JPS SNV12 voter and telco for transport of all the audio and signaling. I have been going through getting all the RX levels to the voter to arrive at my 66 block to the voter at -20 for 1.3k, so that is leveling out the mis-voting. Running all stations with demph audio, and pre emph still enabled on the stations with the notch filters since were running status and keying tones across the lines, changed the TX audio to 2.5k from 4 and have lost definition to the audio. In other words it now sound very flat and not having much articulation.
Question(s) I have here is that in the narrow mode I have noticed in the TX wireline setting unlike wide band there is almost ZERO difference on what input level you drive the line at to achieve 1.3k of deviation at 1k. I have experienced this in 5 stations now.
Additionally I have noticed a loss of fidelity to the systems transmitted audio? I know its less audio but I didnt expect to hear so much difference in the quality of the repeated audio. My MDC muting isn't functional on my portable like it once was either. Is this normal? I have swept he phone line too look for roll off on the lines and some may have 1-2 db on the low end but still seem to hold fine above 1khz. I do not have AUTO or AGC enabled on the station wireline anywhere in the RSS.
Am I missing something? Thanks!
Have been cleaning up a guys work here in the county that left and found that he left all the county's Quantar stations set to 4k deviation not 2.5. I have 3 systems that use the JPS SNV12 voter and telco for transport of all the audio and signaling. I have been going through getting all the RX levels to the voter to arrive at my 66 block to the voter at -20 for 1.3k, so that is leveling out the mis-voting. Running all stations with demph audio, and pre emph still enabled on the stations with the notch filters since were running status and keying tones across the lines, changed the TX audio to 2.5k from 4 and have lost definition to the audio. In other words it now sound very flat and not having much articulation.
Question(s) I have here is that in the narrow mode I have noticed in the TX wireline setting unlike wide band there is almost ZERO difference on what input level you drive the line at to achieve 1.3k of deviation at 1k. I have experienced this in 5 stations now.
Additionally I have noticed a loss of fidelity to the systems transmitted audio? I know its less audio but I didnt expect to hear so much difference in the quality of the repeated audio. My MDC muting isn't functional on my portable like it once was either. Is this normal? I have swept he phone line too look for roll off on the lines and some may have 1-2 db on the low end but still seem to hold fine above 1khz. I do not have AUTO or AGC enabled on the station wireline anywhere in the RSS.
Am I missing something? Thanks!