I have decided to build an allstar node. Got the radio, got the account, got the URI, got the Linux box, got the software, now I have to build the cable and put it all together. But in looking at the cable description on the DMKeng site, I don't see any COS signal used. http://www.dmkeng.com/images/9080-GM300.pdf Isn't the COS from the radio needed to suppress transmitting dead autio over the network? I thought a COS signal was required. It's talked about as necessary but the signal isn't shown in the gm300 cable description. Anyone care to explain why this is not needed or when it is needed? And if it is needed, which pin on the 25 connector would it go to? Mike
On 10/04/2013 5:05 PM, Mike wrote:
I have decided to build an allstar node. Got the radio, got the account, got the URI, got the Linux box, got the software, now I have to build the cable and put it all together.
But in looking at the cable description on the DMKeng site, I don't see any COS signal used.
http://www.dmkeng.com/images/9080-GM300.pdf
Isn't the COS from the radio needed to suppress transmitting dead autio over the network? I thought a COS signal was required. It's talked about as necessary but the signal isn't shown in the gm300 cable description.
Anyone care to explain why this is not needed or when it is needed? And if it is needed, which pin on the 25 connector would it go to?
<-- Hi Mike; Welcome to Allstar! - the diagram that you reference above shows the use of "flat audio" from the GM300. I often get questions about the RX audio and my response is usually, "raw discriminator audio, with a flat frequency response from a few Hz up to around 5kHz" The Allstar (app_rpt) software can be setup to use DSP - i.e., it can decode the raw audio to detect PL.... this method is much faster than using a COS line, which can sometimes be very sluggish. So for this reason, COS is not mandatory - assuming that the radio of choice can provide the raw discim audio with a flat frequency response; and the GM300 can. Hope this helps.... I am on a train and approaching my stop. Cheers! Ramesh. Admin for many things!
you did a way better job them me at explaining this ;-))) -----Message d'origine----- From: Ramesh Dhami (VA3UV) Sent: Wednesday, April 10, 2013 5:16 PM To: app_rpt-users@ohnosec.org Subject: Re: [App_rpt-users] GM300 Cable pinout question On 10/04/2013 5:05 PM, Mike wrote:
I have decided to build an allstar node. Got the radio, got the account, got the URI, got the Linux box, got the software, now I have to build the cable and put it all together.
But in looking at the cable description on the DMKeng site, I don't see any COS signal used.
http://www.dmkeng.com/images/9080-GM300.pdf
Isn't the COS from the radio needed to suppress transmitting dead autio over the network? I thought a COS signal was required. It's talked about as necessary but the signal isn't shown in the gm300 cable description.
Anyone care to explain why this is not needed or when it is needed? And if it is needed, which pin on the 25 connector would it go to?
<-- Hi Mike; Welcome to Allstar! - the diagram that you reference above shows the use of "flat audio" from the GM300. I often get questions about the RX audio and my response is usually, "raw discriminator audio, with a flat frequency response from a few Hz up to around 5kHz" The Allstar (app_rpt) software can be setup to use DSP - i.e., it can decode the raw audio to detect PL.... this method is much faster than using a COS line, which can sometimes be very sluggish. So for this reason, COS is not mandatory - assuming that the radio of choice can provide the raw discim audio with a flat frequency response; and the GM300 can. Hope this helps.... I am on a train and approaching my stop. Cheers! Ramesh. Admin for many things! _______________________________________________ App_rpt-users mailing list App_rpt-users@ohnosec.org http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users
On 10/04/2013 5:05 PM, Mike wrote:
I have decided to build an allstar node. Got the radio, got the account, got the URI, got the Linux box, got the software, now I have to build the cable and put it all together.
But in looking at the cable description on the DMKeng site, I don't see any COS signal used.
http://www.dmkeng.com/images/9080-GM300.pdf
Isn't the COS from the radio needed to suppress transmitting dead autio over the network? I thought a COS signal was required. It's talked about as necessary but the signal isn't shown in the gm300 cable description.
Anyone care to explain why this is not needed or when it is needed? And if it is needed, which pin on the 25 connector would it go to?
<-- Hi Mike; Welcome to Allstar! - the diagram that you reference above shows the use of "flat audio" from the GM300. I often get questions about the RX audio and my response is usually, "raw discriminator audio, with a flat frequency response from a few Hz up to around 5kHz"
The Allstar (app_rpt) software can be setup to use DSP - i.e., it can decode the raw audio to detect PL.... this method is much faster than using a COS line, which can sometimes be very sluggish.
So for this reason, COS is not mandatory - assuming that the radio of choice can provide the raw discim audio with a flat frequency response; and the GM300 can.
Hope this helps.... I am on a train and approaching my stop.
Cheers!
Ramesh. Admin for many things!
So, let me see if I understand this. 1) The DSP chip inside the URI can decode the COS and know when it's present. Therefore, having a separate COS isn't required. 2) Since the diagram shows wiring for this case, can I assume that pin 11, on the GM300 connector, is the correct RX to use, use for receive audio, to the URI? 3) Is there anything else required (changes inside the radio) for this wor work correctly? 4) Since the tone is decoded in the DSP, where do I specify what that tone is, so the app_rpt software knows what tone to look for? Mike
1) The DSP chip inside the URI can decode the COS and know when it's present. Therefore, having a separate COS isn't required. No there is no DPS chip on the URI, this is done by the DSP code in the computer. 2) Since the diagram shows wiring for this case, can I assume that pin 11, on the GM300 connector, is the correct RX to use, use for receive audio, to the URI? Yes, Pin 11 is correct for this if JU551 is in position A 3) Is there anything else required (changes inside the radio) for this wor work correctly? See Above. 4) Since the tone is decoded in the DSP, where do I specify what that tone is, so the app_rpt software knows what tone to look for? /etc/asterisk/usbradio.conf Mike _______________________________________________ App_rpt-users mailing list App_rpt-users@ohnosec.org http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users
Its simply cause the app_rpt app will detect the cos by dsp and the same will be done for any ctcss tone you want. That if you use USBRADIO If you use SIMPLEUSB you will need to to provide COS and ctcss if you want ctcss. -----Message d'origine----- From: Mike Sent: Wednesday, April 10, 2013 5:05 PM To: app_rpt-users@ohnosec.org Subject: [App_rpt-users] GM300 Cable pinout question I have decided to build an allstar node. Got the radio, got the account, got the URI, got the Linux box, got the software, now I have to build the cable and put it all together. But in looking at the cable description on the DMKeng site, I don't see any COS signal used. http://www.dmkeng.com/images/9080-GM300.pdf Isn't the COS from the radio needed to suppress transmitting dead autio over the network? I thought a COS signal was required. It's talked about as necessary but the signal isn't shown in the gm300 cable description. Anyone care to explain why this is not needed or when it is needed? And if it is needed, which pin on the 25 connector would it go to? Mike _______________________________________________ App_rpt-users mailing list App_rpt-users@ohnosec.org http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users
the COS/COR is not needed because the settings in the usbradio.conf are going to be: carrierfrom=dsp ctcssfrom=dsp The Linux box is going to use DSP to detect the the difference between the white noise and a modulated signal. Once it detects that difference, it will send the audio over the network to whatever node you are connected to. Ensure that you use the radio-tune-menu after you make the setting adjustments and reboot. The radio-tune-menu going through the steps will help you ensure that your audio into the network is set to the proper deviation, ability to detect the difference between white noise and an actual signal, and proper TX audio levels on your end. This will ensure your TX deviation is set to 3KHz with a 1KHz tone and vise-versa. It is wise to use a service monitor when using the radio-tune-menu. If you do not have access to one, become a friend with someone who does, or ask members of your radio club. I'm after two or three hours of pure, continuous looking, you will find someone who has one. The allstarlink.org website has an alternative method that uses a radio that should be known accurate. Meaning it's TX audio deviation is correct, and it's on frequency, as best as a amateur radio is going to be. If you do not have a tone generator, the open source world has plenty of programs that you can use the computer to generate a 1KHz tone. It's not complicated, and doesn't take long to setup using a service monitor. Once you go through the steps, the last step will be to save what you've done and then reboot the node. I used the above methods to setup my box, and it's works wonderful. ~Benjamin, KB9LFZ allstar 28569 On Wed, 2013-04-10 at 14:05 -0700, Mike wrote:
I have decided to build an allstar node. Got the radio, got the account, got the URI, got the Linux box, got the software, now I have to build the cable and put it all together.
But in looking at the cable description on the DMKeng site, I don't see any COS signal used.
http://www.dmkeng.com/images/9080-GM300.pdf
Isn't the COS from the radio needed to suppress transmitting dead autio over the network? I thought a COS signal was required. It's talked about as necessary but the signal isn't shown in the gm300 cable description.
Anyone care to explain why this is not needed or when it is needed? And if it is needed, which pin on the 25 connector would it go to?
Mike _______________________________________________ App_rpt-users mailing list App_rpt-users@ohnosec.org http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users
participants (5)
-
Benjamin L. Naber -
Mike -
pete M -
Ramesh Dhami (VA3UV) -
Scott Weis