[App_rpt-users] Problem getting RTCM to process received audio

Tim Sawyer tisawyer at gmail.com
Sun Nov 26 04:22:05 UTC 2017


The third problem has to be solved first. That will probably correct the
others. The RTCM noise squelch circuit want to see unfiltered and
unsquelched discriminator audio in order to work in voting applications.
Check to insure that the audio out of your radios is discriminator audio.
If not, you'll have to find another output or program the radio.

On Sat, Nov 25, 2017 at 9:18 AM, Doug Kingston <dpk at randomnotes.org> wrote:

> I am trying to prototype a RTCM based voting system with 2 RTCMs.
> I am using two JSLM2 Data Radios as transceivers.
> Using HP8920B service monitor to drive the radios.
>
> Good news: I can get both RTCMs and both radios to transmit.  Test tones
> sound fine. Deviation good.
>
> Bad news: I can't get the RTCMs to register the incoming audio signal.  There
> is no CTCSS in these radios, so that line is not connected.  I have no COS
> signal connected either.  Just audio in/out and PTT to the radio.
>
> I have confirmed the radios are receiving and are sending audio to the
> RTCMs using an oscilloscope.  If anything the audio is way high in level.
> I measured 1v peak-to-peak when I think the RTCM is expecting 200mV.  Tried
> the 20db pad with no effect.  My suspicion is that the RTCM is a
> high-impedance input so the voltage is floating up in the absence of
> appropriate load (say from a 600 or 2k ohm).
>
> Second, I never get the green receive light on so I suspect there is
> actually some squelching or some such going on that is gating the audio
> signal off.
>
> Third, I have not been able to the the Squelch calibration or Diode
> calibration to behave.  Does this require the diagnostic cable described in
> the interface to be used?  The procedure is not documented well.
>
> I would love to see a know working config and wiring setup to confirm what
> I have done.
>
> -Doug-
>
> Current settings:
>
> Select the following values to View/Modify:
>
> S/W Version: 1.51 08/08/2017
> System Uptime: 2095.0 Secs
> IP Address: 192.168.0.75
> Netmask: 255.255.255.0
> Gateway: 192.168.0.1
> Primary DNS: 192.168.0.1
> Secondary DNS: 192.168.0.1
> DHCP: 1
> VOTER Server IP: 104.197.124.184
> VOTER Server UDP Port: 667
> OUR UDP Port: 667
> GPS Lock: 1
> Connected: 0
> COR: 0
> EXT CTCSS IN: 1
> PTT: 0
> RSSI: 0
> Current Samples / Sec.: 8000
> Current Peak Audio Level: 112
> Squelch Noise Gain Value: 0, Diode Cal. Value: 0, SQL pot 0
> Current Time: Sat  Nov 25, 2017  17:14:12.740
> Last Rx Pkt System time: <System Time Not Set>, diff: -198435452 msec
> Last Rx Pkt Timestamp time: <System Time Not Set>, diff: 0 msec
> Last Rx Pkt index: 0, inbounds: 0
>
> 1  - Serial # (1162) (which is MAC ADDR 00:04:A3:00:04:8A)
> 2  - VOTER Server Address (FQDN) (xxx.org)
> 3  - VOTER Server Port (667),  4  - Local Port (Override) (0)
> 5  - Client Password (xxx1),  6  - Host Password (xxx2)
> 7  - Tx Buffer Length (3000)
> 8  - GPS Data Protocol (0=NMEA, 1=TSIP) (0)
> 9  - GPS Serial Polarity (0=Non-Inverted, 1=Inverted) (0)
> 10 - GPS PPS Polarity (0=Non-Inverted, 1=Inverted, 2=NONE) (0)
> 11 - GPS Baud Rate (4800)
> 12 - External CTCSS (0=Ignore, 1=Non-Inverted, 2=Inverted) (0)
> 13 - COR Type (0=Normal, 1=IGNORE COR, 2=No Receiver) (0)
> 14 - Debug Level (0)
> 15  - Alt. VOTER Server Address (FQDN) ()
> 16  - Alt. VOTER Server Port (Override) (0)
> 17  - DSP/BEW Mode NOT SUPPORTED
> 18 - "Duplex Mode 3" (0=DISABLED, 1-255 Hang Time) (1/10 secs) (0)
> 19 - Simulcast Launch Delay (600) (approx 200 ns, 5 = 1us, > 0 to ENA SC)
> 97 - RX Level,  98 - Status,  99 - Save Values to EEPROM
> i - IP Parameters menu, o - Offline Mode Parameters menu
> q - Disconnect Remote Console Session, r - reboot system, d - diagnostics
>
>
>
> _______________________________________________
> App_rpt-users mailing list
> App_rpt-users at lists.allstarlink.org
> http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users
>
> To unsubscribe from this list please visit http://lists.allstarlink.org/
> cgi-bin/mailman/listinfo/app_rpt-users and scroll down to the bottom of
> the page. Enter your email address and press the "Unsubscribe or edit
> options button"
> You do not need a password to unsubscribe, you can do it via email
> confirmation. If you have trouble unsubscribing, please send a message to
> the list detailing the problem.
>



-- 
--
Tim
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.keekles.org/pipermail/app_rpt-users/attachments/20171125/6dedecf1/attachment.html>


More information about the App_rpt-users mailing list