clipping in transmission

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LA9ULA
Posts: 43
Joined: Sat Aug 17, 2019 7:14 pm

clipping in transmission

Post by LA9ULA »

Fusion to YSF, or crossmode to DMR.
I have reports of clipping in my transmission. Not always, but most of the time. In between I have apparently good audio. I have also never been able to get autocal to respond (never finish) or any echo service to play back anything. Looking at RSSI it sometimes looks like below. Occurs with different antennas and power settings. It seems like these dropouts are more likely to occur when I bring my handheld up close to my face for speaking. There are no similar dropouts in received signal strengt using another FM radio to monitor so it appears the radio is transmitting all the time. However, the OS2 does not register a signal once in a while - is that possible?.I don't think the radio transmit frequency is off. What could be the cause, radio or OS2?
I have not been able to check directly with another Fusion radio.

Any advice would be greatly appreciated.

Regards
Bjørnung
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OS2 RSSI.JPG
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HA2NON
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Re: clipping in transmission

Post by HA2NON »

Please first test the connection between your transceiver and the OS2 using the OS2's built-in local echo service. http://manuals.sharkrf.com/openspot2/en ... calls.html
Do you hear yourself back correctly?
Norbert Varga, HA2NON
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LA9ULA
Posts: 43
Joined: Sat Aug 17, 2019 7:14 pm

Re: clipping in transmission

Post by LA9ULA »

I have tried, but as mentioned never got this to play back anything. Below is the settings I have, maybe I am doing this wrong. Is all I have to do change the DG-ID settings in the radio from Auto to 99?
(there is no "0" settings as sometimes referred to in the OS2 manual. Only 1-99, and Auto)

I do hear other stations fine.

Regards
Bjørnung
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C4FM settings.JPG
status ysf.JPG
LA9ULA
Posts: 43
Joined: Sat Aug 17, 2019 7:14 pm

Re: clipping in transmission

Post by LA9ULA »

Additional info.
It appears that the log says "C4FMcalltracker: invalid fich" whenever the signal drops to zero. Don't know what that indicates?

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HA2NON
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Re: clipping in transmission

Post by HA2NON »

Yes, all you need to do is to change both RX and TX DGID to 99 to do an echo test. Please make sure that your transceiver is outputting enough power, and it's antenna is connected properly. Invalid FICH means the OS2 was not able to decode the frame as it had too many errors.
Norbert Varga, HA2NON
SharkRF Team
LA9ULA
Posts: 43
Joined: Sat Aug 17, 2019 7:14 pm

Re: clipping in transmission

Post by LA9ULA »

My apologies for not coming back earlier. I finally managed to get the echo to work, my mistake in the settings. Yes, I sound fine on the audio and now gets good report on that as long as I take care about the below issues:

I found there is an issue with having APRS on in the background on the OS2, I noted that this already have been reported by others and that you plan to fix this is next update. Great - many thanks for that. :D

I still have problems with the signal in to the OS2 dropping out at shown earlier in the picture of the RSSI. I find that if I move the radio only a few cm I might find a spot where the signal drops out completely, or goes up and down. I confirmed today that this is so also happening when using my mobile phone as a hotspot while away from my QTH. There seems to be a slight change in how severe this is depending on which frequency I use, but not much.
Could this be strong local interference of some kind?

At home I find I need to watch the RSSI when talking so that I can see if I advertently should move a little bit and the signals drops to zero. As mentioned there seems to be no issue with the radio with respect to power out, antenna connection etc. Sorry if this might not be related to the OS2, but perhaps someone has an idea of what this could be. My next plan is to wrap the body of the radio in some aluminium foil to see if this just might shield the radio. Long shot but...

Regards
Bjørnung
k9agr
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Joined: Sun Jun 10, 2018 8:59 pm

Re: clipping in transmission

Post by k9agr »

Resurrecting an old thread I know, but for anyone else searching for that invalid fich error, this might help.

I had my OS2 set for C4FM Half Deviation (which I assumed was Narrow), and selected DN mode on the FT70 (assuming DN = Digital Narrow) but menu 62 on the radio was set to WIDE. Setting the OS2 and radio to match (C4FM and Wide, or C4FM Half Deviation and Narrow) resolved it.

I would have tried the echo test, but how in the bleep does one change the DG-ID on the FT-70?

Hope this helps someone else some day.
Jim
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