using chan_usbradio on a pi3 driving a Motorla R100 rptr I'm wondering if my preemphasis and limiting looks good to you guys? I've made changes, and am -not- noticing a difference when I go back to the console and 'reload' or even do an 'astres.sh' at the command line prompt. ~shrug~ Rig is a Motorola R100 using a URIx usbradio.conf looks like: ; ; Usbradio channel driver Configuration File ; [general] [usb_29655] eeprom = 0 ; EEPROM installed: 0,1 ; 0 = no (default) ; 1 = yes hdwtype = 0 ; Leave this set to 0 for USB sound fobs modified using ; the instructions from usbfob.pdf. Use a setting of ; 1 is for Dingotel/Sph interfaces. rxboost = 0 ; 0 - 20db attenuator inserted ; 1 - 20db attenuator removed ; Set to 1 for additonal gain if using a low-level receiver output rxctcssrelax = 1 ; reduce talkoff from radios w/o CTCSS Tx HPF ; Do not change this, leave this as a 1 rxsqhyst = 500 ; Setting Squelch Hysteresis ; 3000 is the default amount. ; An amount of 500 seems good. ; Then set the squelch to the highest number revealed when doing a "radio ; tune rxsquelch" - running the command multiple (like 20) times in a row. ; <http://allstarnode.com/wiki/lib/exe/fetch.php?media=asterisk-notes-wj8g.pdf> ;txctcssdefault = 100.0 ; default tx ctcss freq, any frequency permitted ;rxctcssfreqs = 100.0 ; rx ctcss freqs in floating point. must be in table ;txctcssfreqs = 100.0 ; tx ctcss freqs, any frequency permitted rxctcssoverride = 1 ; Set to 1 or yes to start out in carrier squelch mode carrierfrom = usb ; no,usb,usbinvert,dsp,vox ; no - no carrier detection at all ; usb - from the COR line on the USB sound fob (Active high) ; usbinvert - from the inverted COR line on the USB sound fob (Active low) ; dsp - from RX noise using dsp techniques ; vox - voice activated from RX audio ctcssfrom = usb ; no,usb,usbinvert,dsp ; no - no CTCSS decoding, system will be carrier squelch ; usb - from the CTCSS line on the USB sound fob (Active high) ; usbinvert - from the inverted CTCSS line on the USB sound fob (Active low) ; dsp - CTCSS decoding using RX audio in DSP. ; rxdemod option must be set to flat for this to work. rxdemod = flat ; input type from radio: no,speaker,flat ; no - RX audio input not used ; flat - Use RX audio from discriminator (before de-emphasis) ; speaker - use de-emphasized audio rxsquelchdelay = 30 ; delayline in ms carrier squelch tail eliminator rxondelay = 20 ; Number of 20mSec intervals following the release of PTT. ; Uncomment and/or adjust for simplex nodes to eliminate "Ping Ponging" ; or "Relay Racing". A positive value here will instruct the usbradio ; driver to ignore the COR line for a specified number of 20mSec ; intervals following the release of PTT. Use this ONLY on simplex ; nodes, and leave commented out for repeaters or other full duplex nodes. txboost = 0 ; Add transmitter audio gain boost: 0,1 ;################# ;# section of interest # txprelim = yes ; Audio processing on left output channel: no,yes ; no - Audio is not pre-emphasized and limited. ; Suitable for use on a microphone input ; yes - Audio is pre-emphasized and limited. ; Suitable for direct connection to an FM modulator txlimonly = no ; Audio limiting with no pre-emphasis on output channel: no,yes ; no - Audio is not limited. ; yes - Audio is limited. ; Suitable for transmitters with no limiting but with pre-emphasis. ;# end section of interest # ;################# txtoctype = notone ; Transmit tone control type: no,phase,notone ; no - CTCSS tone encoding with no hang time ; phase - encode CTCSS and reverse phase ; AKA ("reverse burst") before unkeying TX ; notone - encode CTCSS and stop sending tone before unkeying TX ; AKA ("chicken burst") txmixa = composite ; Left channel output: no,voice,tone,composite,auxvoice ; no - Do not output anything ; voice - output voice only ; tone - CTCSS tone only ; composite - voice and tone ; auxvoice - auxiliary voice output at headphone level for monitoring txmixb = no ; Right channel output: no,voice,tone,composite, auxvoice ; no - Do not output anything ; voice - output voice only ; tone - CTCSS tone only ; composite - voice and tone ; auxvoice - auxiliary voice output at headphone level for monitoring invertptt = 0 ; Invert PTT: 0,1 ; 0 - ground to transmit ; 1 - open to transmit ; This is the collector lead of the 2n4401 on the modified ; usb sound fob. ; please refer to the howto for the procedure to do this. duplex = 1 ; Duplex 0,1 ; 0 - half duplex ; 1 - full duplex -- 73 = Best Regards, -Geoff/W5OMR