Land Surveyor Forum

Replies

• 

  Arnel M. Domag September 3, 2012 at 9:56pm

  Thank you for sharing your idea. :)
  
  Tom Homan said:

  While we all want to get our work done, this subject has no easy answer since we work in an area of shared and licensed spectrum. One of the easiest ways to handle RFI is to have a license for more than one frequency. This way if one channel is hammered then flip to the alternate.

  Also, does your RF license authorize you to transmit/consume spectrum at that location? When we first set up our RTK gear our original radio license only authorized us to transmit within an 8 mile radial of our office even though we had responsibility to work in an area of ~4800sq mi. This required a modification to our license. Speaking of which, you do have a copy of your radio license in your work truck don't you? It's the same as if you left your wallet on the dresser and got pulled over by the police. If you don't have the paper in your possession or transmitting in an authorized area then the fault is yours.

  That being said, I've utilized handheld radio scanners with both omni and directional antennas to determine the source of RFI for worksite problems.  Tune the scanner to your licensed transmit frequency and see if things are quiet. If not, then your work is just starting as you as there is nothing intelligible transmitted. In the US, every radio transmitter is required to broadcast the license call sign periodically but most radios do this in morse code rather than voice so decoding who the offending person is might be difficult. Once the station ID was resolved, then it's a matter of checking the FCC database (in the US) to determine station ownership. With a directional antenna you could triangulate to find the transmitter and possibly it's owner based on observed signal strength...

  Ultimately, RF is a shared community and the good neighbor approach applies. The FCC issues the license knowing full well that that you will not be the only person transmitting on a given frequency but they try to minimize conflicts by frequency coordination and geographic dispersal. If you take a job outside your rf licensed area then you might be the problem and not they other guy.

  Just my $0.02

  Tom
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  Arnel M. Domag September 3, 2012 at 9:55pm

  Thank you for sharing the manual. :)
  
  ePalmetto said:

  Hey guys..sorry been away for a while.

  This is the unit we always used in the field, Through the years every survey firm wanted a DEMO. There is nothing easier to kill a good demo, and slow down or stop a project. This product can be ordered from RadioShack, and cost around $100, here is the link to the manual so you can check it out.

  http://www.radioshack.com/graphics/uc/rsk/Support/ProductManuals/20...

  If you don't have FCC freqs. optional purchase, all units are loaded with a set of  freqs pre=loaded, these are standard freqs and can be stepped on easily.

  So the first thing you do is step out a test your standard freq channels to make sure which ones are clear, and I believe you can tell the strength of the signals as well. Always keep it handy, what some would call a bad GPS day....is only because they didnt have the tool to make sure which channel to be on.

  Let me know if i can help.

  Skip Farrow
• GEO Ambassador

  Skip Farrow August 28, 2012 at 3:13pm

  Hey guys..sorry been away for a while.

  This is the unit we always used in the field, Through the years every survey firm wanted a DEMO. There is nothing easier to kill a good demo, and slow down or stop a project. This product can be ordered from RadioShack, and cost around $100, here is the link to the manual so you can check it out.

  http://www.radioshack.com/graphics/uc/rsk/Support/ProductManuals/20...

  If you don't have FCC freqs. optional purchase, all units are loaded with a set of  freqs pre=loaded, these are standard freqs and can be stepped on easily.

  So the first thing you do is step out a test your standard freq channels to make sure which ones are clear, and I believe you can tell the strength of the signals as well. Always keep it handy, what some would call a bad GPS day....is only because they didnt have the tool to make sure which channel to be on.

  Let me know if i can help.

  Skip Farrow
• 

  Tom Homan August 13, 2012 at 3:55pm

  While we all want to get our work done, this subject has no easy answer since we work in an area of shared and licensed spectrum. One of the easiest ways to handle RFI is to have a license for more than one frequency. This way if one channel is hammered then flip to the alternate.

  Also, does your RF license authorize you to transmit/consume spectrum at that location? When we first set up our RTK gear our original radio license only authorized us to transmit within an 8 mile radial of our office even though we had responsibility to work in an area of ~4800sq mi. This required a modification to our license. Speaking of which, you do have a copy of your radio license in your work truck don't you? It's the same as if you left your wallet on the dresser and got pulled over by the police. If you don't have the paper in your possession or transmitting in an authorized area then the fault is yours.

  That being said, I've utilized handheld radio scanners with both omni and directional antennas to determine the source of RFI for worksite problems.  Tune the scanner to your licensed transmit frequency and see if things are quiet. If not, then your work is just starting as you as there is nothing intelligible transmitted. In the US, every radio transmitter is required to broadcast the license call sign periodically but most radios do this in morse code rather than voice so decoding who the offending person is might be difficult. Once the station ID was resolved, then it's a matter of checking the FCC database (in the US) to determine station ownership. With a directional antenna you could triangulate to find the transmitter and possibly it's owner based on observed signal strength...

  Ultimately, RF is a shared community and the good neighbor approach applies. The FCC issues the license knowing full well that that you will not be the only person transmitting on a given frequency but they try to minimize conflicts by frequency coordination and geographic dispersal. If you take a job outside your rf licensed area then you might be the problem and not they other guy.

  Just my $0.02

  Tom
• 

  Arnel M. Domag August 3, 2012 at 10:44pm

  I am also interested about this topic. I experienced this type of radio link failure.