Author Topic: Noise at the beginning of transmission  (Read 8116 times)

K1IKE-Joe

  • Jr. Member
  • **
  • Posts: 94
    • View Profile
    • Email
Noise at the beginning of transmission
« on: 2014-04-22, 01:41:28 »
When I first press the PTT there is noise on the RF transmitted signal.  Once a word is spoken, the noise goes away and does not return until the next PTT transmission.

TS480SAT
RRC-1258MkIIs
RRC-Micro  PC-Client 1.6.12

Any ideas?

Joe

K1IKE-Joe

  • Jr. Member
  • **
  • Posts: 94
    • View Profile
    • Email
Re: Noise at the beginning of transmission
« Reply #1 on: 2014-05-09, 15:50:16 »
Here is a recording of the noise.

Joe, K1ike

sm2o

  • Administrator
  • Hero Member
  • *****
  • Posts: 2944
    • View Profile
    • sm2oan
    • Email
Re: Noise at the beginning of transmission
« Reply #2 on: 2014-05-15, 08:44:32 »
Sounds like some AGC function is activated in the PC, there is no AGC in the Remoterig system so it must be outside.

/mike

K1IKE-Joe

  • Jr. Member
  • **
  • Posts: 94
    • View Profile
    • Email
Re: Noise at the beginning of transmission
« Reply #3 on: 2014-05-15, 14:07:01 »
Thank you for the reply, we will look into it.

73, Joe, K1ike

K1IKE-Joe

  • Jr. Member
  • **
  • Posts: 94
    • View Profile
    • Email
Re: Noise at the beginning of transmission
« Reply #4 on: 2014-05-25, 21:13:10 »
We looked at the setup of the computer (laptop) and found nothing that would cause an AGC effect.  The MicroPC dongle was moved to a desktop computer and we are still having the same noise problem.  As long as there is modulation it is fine, but the noise creeps back up when you are silent and the radio is keyed.

No ideas at this point.

Joe

sm2o

  • Administrator
  • Hero Member
  • *****
  • Posts: 2944
    • View Profile
    • sm2oan
    • Email
Re: Noise at the beginning of transmission
« Reply #5 on: 2014-05-25, 21:41:13 »
Hi

I haven't heard about this problem before, You can test with another soundcard, you do not need to use the RRC-Micro dongle as soundcard. If you have for example a USB headset you can setup the RRC-Micro software to use it,and compare how it behaves. As I wrote before there is no AGC in the Remoterig box or PC-software.

73 de mike

K7RBO

  • Newbie
  • *
  • Posts: 1
    • View Profile
Re: Noise at the beginning of transmission
« Reply #6 on: 2014-05-27, 17:13:37 »
Hi,

Having same problem. only solution I have found is to turn mic gain way down. But most stations keep saying
that there is some type of noise until you start talking.
I have  tried three different computers. 1 desktop, 2 laptops and they all have same issues. tired many different settings on boxes, but still have issue.

Thanks for the help,

Tim

sm2o

  • Administrator
  • Hero Member
  • *****
  • Posts: 2944
    • View Profile
    • sm2oan
    • Email
Re: Noise at the beginning of transmission
« Reply #7 on: 2014-05-27, 21:15:13 »
Hi

But you do not tell if you have tested anyther soundcard or USB-headset, to eliminiate eventual problem with the RRC-Micro.

73 de mike

K1IKE-Joe

  • Jr. Member
  • **
  • Posts: 94
    • View Profile
    • Email
Re: Noise at the beginning of transmission
« Reply #8 on: 2014-06-04, 02:06:21 »
It is happening with the other sound card too.  I unplugged the headset from the MicroPC dongle and I still have audio being transmitted.  It appears that the microphone in the laptop is always active.  This appears to be causing the noise that I am hearing (feedback).

With the headset unplugged from the dongle I can select Microphone (Microbit 1274A), Microphone (Realtek High Defini, or Line (Microbit 1274A) In all cases, the microphone in the laptop is active and I can hear my voice beibng transmitted over the air.  This is with no headset plugged into the dongle.

Joe
 

K1IKE-Joe

  • Jr. Member
  • **
  • Posts: 94
    • View Profile
    • Email
Re: Noise at the beginning of transmission
« Reply #9 on: 2014-06-05, 01:22:48 »
I uninstalled the MicroPC software and reinstalled it. now it appears to be functioning well, but I still get the noise on transmit.  Moving the microphone slider on the MicroPC control panel varies the volume of the noise, so it appears to be originating from the MicroPC dongle side of the Internet connection.

When I use the RemoteRig 1258 control head to operate the station all is OK.  It looks like there is a problem with the MicroPC dongle.  This is the third computer that is acting like this.  I am unable to switch to the sound card in the computer, the sound card in the MicroPC stays active.

Would it be possible for someone to access my station with their dongle and see if the same condition exists?

73, Joe, K1ike

sm2o

  • Administrator
  • Hero Member
  • *****
  • Posts: 2944
    • View Profile
    • sm2oan
    • Email
Re: Noise at the beginning of transmission
« Reply #10 on: 2014-06-05, 08:08:31 »
Hi

Roland can try to help you to switch soundcard via teamviewer if you install it.

I don't think there is anything wrong, I think it's more the characteristics of the microphone which is different. The Mic you use connected to the PC probably pics up much more of the surounding noise from PC-fans etc than the orginal TS-480 microphone.

But if we can change to another soundcard we will know if it's related to to the Dongle or to something else

/mike

K1IKE-Joe

  • Jr. Member
  • **
  • Posts: 94
    • View Profile
    • Email
Re: Noise at the beginning of transmission
« Reply #11 on: 2014-06-05, 11:29:24 »
Hello Mike,

Thank you for the reply.  The noise happens even when the headset microphone is unplugged from the dongle.  I will verify this again just to be sure.

I have just recently switched from LogMeIn to Teamviewer and I need to set TV up on my laptop that the dongle is plugged into.  I will get things ready. 

73, Joe, K1ike

K1IKE-Joe

  • Jr. Member
  • **
  • Posts: 94
    • View Profile
    • Email
Re: Noise at the beginning of transmission
« Reply #12 on: 2014-06-05, 12:07:28 »
Hello Again,

I just verified that the noise happens when the headset microphone is disconnected.  Actually, the noise gets much louder with the microphone unplugged from the dongle.  I unplugged the AC power from the laptop and the noise went away!

My friend had the dongle originally and I just have had the opportunity to test it locally.  The noise appears to be coming from the AC adapter for the laptop.  My friend had tried it on his desktop and had the same problem with noise.  I did replace the USB cable that connects to the dongle with a known good one and verified that the noise is still there.

So, in conclusion, the dongle appears to work just fine without the AC connected to the computer.  When the AC adapter is connected to the laptop AC hum is transmitted over the microphone input to the dongle.  I will install it on my desktop sometime today and verifiy that I am having the same problem using the desktop computer as my friend did.

73, Joe, K1ike

K1IKE-Joe

  • Jr. Member
  • **
  • Posts: 94
    • View Profile
    • Email
Re: Noise at the beginning of transmission
« Reply #13 on: 2014-07-07, 00:06:45 »
I had gotten away from this project until now.  The TS-480SAT still makes a noise with the mike cable coming from the RemoteRig disconnected from the radio, so I am beginning to think the problem is with the TS-480SAT.  I'll have to wait until I get the radio head to the site and test just the radio without the RemoteRig equipment.  Right now, the TS-480 head is 1,000 miles away so it might be a while until I can test it.

Thanks for your help.

73, Joe, K1ike