Page 1 of 2 12 LastLast
Results 1 to 15 of 17

Thread: Radio Mode Questions

  1. #1
    Member jdixon485's Avatar
    Join Date
    Feb 2011
    Location
    Seatac, WA
    Posts
    32
    Years of Experience
    10
    Rep Power
    8

    Default Radio Mode Questions

    What signal range does 'Radio Mode' detect? I saw on some locate manual 15-27khz is the detectable range - is that standard for most equipment that has a 'Radio Mode' function? Or does it search for a broader band of ranges? Is it possible to send out a very high frequency using an RF signal generator and use radio mode to pick it up - to make it more efficient on a blind sweep per say?

  2. #2
    Member DigScout's Avatar
    Join Date
    Mar 2011
    Location
    www.digscout.com
    Posts
    31
    Rep Power
    8

    Default Re: Radio Mode Questions

    I believe it depends on the manufacturer. I heard that with the RD8000, they increased the radio band on the radio passive to be more open and receptive to signals, and narrowed the power band on the power passive to be less receptive to power signals.

    This is all in comparison to the rd4000 of course. I have used both and agree with what I have been hearing. I heard it from the local distributor. The narrow power band is a step in the wrong direction I feel, it's more useful for duct banks in the cities but not as helpful on service drops now that it doesn't tone them as much. For example I can't find small 25 pair rural telephone main cables with the rd8000 power passive, but with the rd4000, it may be possible.

    The radio band increase is a good choice, though. I find myself using it almost exclusively for finding a place to drop my transmitter and it has been just great.

  3. #3
    Senior Member sauroke's Avatar
    Join Date
    Sep 2010
    Location
    Under Heaven's Skies
    Posts
    182
    Years of Experience
    10
    Rep Power
    15

    Default Re: Radio Mode Questions

    I agree with you on the narrow power band, and th increase in radio, but I would never try to find things such as a 25 pr with either. I had a chance to use power mode on a duct bank once with the 8000. Another locator had done this and had marked the duct 6 ft off! I didn't have time to pump out the manhole as the water main break was blocking a major intersection, so I resorted to grounding away, and dropping my pos. lead into the water in the manhole. Marked it out, and the water company went to town.
    By the way, I knew the duct was marked incorrectly in the beginning because I have located it over 10 times in the past 2 years.
    I can usually find secondaries to houses using power, but irrigation lines, sometimes water lines, and dog fences can throw it off.

  4. #4
    Member
    Join Date
    Jul 2012
    Location
    IN A VAN. DOWN BY THE RIVER !
    Posts
    68
    Years of Experience
    5
    Rep Power
    8

    Default Re: Radio Mode Questions

    Hey jdixon.........think about this, The "RF signal generator" you asked about is simply the transmitter we use everyday (well, most of us). When you are direct connected to a utility, then you a placing a "radio" frequency on that utility. I'm not sure about the frequency range that "radio" mode covers and it may differ from Manufacturer to Manufacturer. When direct connected and trying to locate long distances or a cable that I suspect will be deep and even if I have a weak signal in general, I use radio mode to help me verify the utility I'm locating (Like "peak and null", It's another tool you can use). This seems to work with the frequencies I use most often (8,32, 65,512). I'm a big fan of "radio" mode!

  5. #5
    Member
    Join Date
    Jun 2012
    Location
    United States
    Posts
    49
    Rep Power
    7

    Default Re: Radio Mode Questions

    Quote Originally Posted by second notice View Post
    Hey jdixon.........think about this, The "RF signal generator" you asked about is simply the transmitter we use everyday (well, most of us). When you are direct connected to a utility, then you a placing a "radio" frequency on that utility. I'm not sure about the frequency range that "radio" mode covers and it may differ from Manufacturer to Manufacturer. When direct connected and trying to locate long distances or a cable that I suspect will be deep and even if I have a weak signal in general, I use radio mode to help me verify the utility I'm locating (Like "peak and null", It's another tool you can use). This seems to work with the frequencies I use most often (8,32, 65,512). I'm a big fan of "radio" mode!
    When you switch to radio, are you using it to boost the receivers ability to pick up the transmitters signal better? Are you shutting down the transmitter while in radio to get a better locate?

  6. #6
    Mke
    Mke is offline
    Senior Member Mke's Avatar
    Join Date
    Oct 2008
    Location
    Republic of Washington
    Posts
    1,536
    Years of Experience
    16
    Blog Entries
    34
    Rep Power
    77

    Default Re: Radio Mode Questions

    Gettinit,

    I think neither........

    When you switch to radio or passive mode, it searches for this LF band that is constantly out there. It does not increase the transmitters signal Nor does it shut down the transmitter while in the radio mode. The transmitter does not play a part in the passive sweep in radio mode. And it deffinately does not aid in a better locate. It is another way to blind sweep to look for utilities. Passive mode, like induction are great tools when used properly.

    Mke

  7. #7
    Member jdixon485's Avatar
    Join Date
    Feb 2011
    Location
    Seatac, WA
    Posts
    32
    Years of Experience
    10
    Rep Power
    8

    Default Re: Radio Mode Questions

    I understand the concepts of radio mode semi-descently. (And I barely use passive locating except maybe to hear the tone on power mode occasionally as a verification, which I still don't really consider an honest verification...) The reason I inquire about the details of radio mode, and RF signal generators is because I am wondering if you could increase the usefulness of radio mode by basically using a RF generator (which can push the signal with 10x more power) which then can be picked up with using 'radio mode.' Basically, is their any practical scenario where it would be useful to muster up your own transmitter that emits low frequencies with higher power pushing it further then say a 10w transmitter. (I know FCC has very strict guidelines that prohibit more then 10w I believe) But none the less, curious to see how this would work for blind sweeping. I know low frequencies have less capacitance, but with higher power increasing the capacitance at the same time - I am curious if anyone has tried it, or can speculate more on its possible effectiveness. I obviously wouldn't condone breaking FCC guidelines, as this is all hypothetical. But could be semi-useful for someone who say only has a 1watt or 3watt transmitter and wants to bump it up for 10 and have another tool in the bag for blind sweeping.

  8. #8
    Member
    Join Date
    Jul 2012
    Location
    IN A VAN. DOWN BY THE RIVER !
    Posts
    68
    Years of Experience
    5
    Rep Power
    8

    Default Re: Radio Mode Questions

    Mke & Gettinit,

    I agree that "radio" is another way to blind sweep for utilities. But, I disagree that "radio" mode does not aid in a better locate (respectfully disagree, of course!). To address Gettinit's question, I believe you can increase "radio" mode usefulness. Try this sometime........blind sweep an area for fiber/cable/telecom, power, steel gas mains (some CI will "radio" passively), or even some water lines. You might pick your target up blind sweeping in "radio" mode, then again, you might not..... your target might be too deep and/or it's just not large enough to be picked up with "radio" mode. Now, direct connect to the cable, locate it with whatever frequency you deem appropriate. After you locate the cable, switch to "radio" mode on your receiver (leaving transmitter connected) and see what you get along the same path. Your "radio" mode response most likely will be greater than it was when passively sweeping the area. If your direct connect signal was weak, erratic, or maybe you just had a hard time getting a good ground (dry, sandy, rocky soil, etc.) and you're just not sure, an elevated "radio" mode signal helps confirm the direct connect signal. Just make sure you know the area well enough to rule out other utilities in the ground. I have picked up water, gas, power and telecom blind sweeping radio mode. When direct connected to these utilities, usually (90%)the "radio" mode signal is much greater than when I passively swept the area. I just happen to work for a company that locates 4/5 utilities in the area. This makes things a bit easier when you can rule other utilities out.

  9. #9
    Senior Member UTILQ1's Avatar
    Join Date
    Dec 2011
    Location
    Morgan Cty, Wv
    Posts
    106
    Rep Power
    10

    Default Re: Radio Mode Questions

    I think until someone states that the transmitter frequency output matches the reciever frequnecy reception for radio or passive than the application would have no effect...

    It is an interesting area to experiment with if one could transmit those frequenccies into a conductor to exploit the use on the reciever...



    good topic...

  10. #10
    Member
    Join Date
    Jul 2012
    Location
    IN A VAN. DOWN BY THE RIVER !
    Posts
    68
    Years of Experience
    5
    Rep Power
    8

    Default Re: Radio Mode Questions

    no matching transmitter frequency needed................Here is a good explanation of the electromagnetic spectrum. http://www.infocellar.com/networks/w...s/spectrum.htm

    "Radio" waves are technically light waves between the 30Hz and 300Mhz frequencies in the low frequency, low energy of the EMF. "Radio" gets 'em all .

  11. #11
    Member spencer newson's Avatar
    Join Date
    Dec 2009
    Location
    devon united kingdom
    Posts
    50
    Rep Power
    10

    Default Re: Radio Mode Questions

    mike,

    i totally agree with what you say, in our line of work it is our responsability to illiminate every service methodically, passive modes are very handy to orientate yourself on site, but once this is achieved transmitters are a must, i allways start with power then comms then gas and water its a good system on illiminating the services, plus during your power sweeps you can get cross over signals which throws a spanner in the works, but this i my mind focuses me even more (never assume you are on the power) i know the 8000 has a pretty good depth indicator in passive power mode, in my experience the radio mode isnt all that, i allways carry the old rd400 in my truck and i believe its radio mode can out smart the 8000 pretty much every time, i dont know why but it does!
    i guess everyone has there perferred tool.


    bugger what was the question?

  12. #12
    Senior Member UTILQ1's Avatar
    Join Date
    Dec 2011
    Location
    Morgan Cty, Wv
    Posts
    106
    Rep Power
    10

    Default Re: Radio Mode Questions

    Quote Originally Posted by second notice View Post
    no matching transmitter frequency needed................Here is a good explanation of the electromagnetic spectrum. http://www.infocellar.com/networks/w...s/spectrum.htm

    "Radio" waves are technically light waves between the 30Hz and 300Mhz frequencies in the low frequency, low energy of the EMF. "Radio" gets 'em all .
    Its getting above my head without further edumacation - what I am beginning to see is variables involving if receivers are calibrated tojust a portion of the radio frequencies or not?
    Also if all receivers do cover the entire spectrum may be a part of the spectrum is inaudible which narrows down the frequencies to the audible ones which some may or may not be more audible than others depending on how much power is or is not induced on the said frequency?
    Last edited by UTILQ1; August 25th, 2012 at 03:10 AM.

  13. #13
    Senior Member UTILQ1's Avatar
    Join Date
    Dec 2011
    Location
    Morgan Cty, Wv
    Posts
    106
    Rep Power
    10

    Default Re: Radio Mode Questions

    Quote Originally Posted by spencer newson View Post

    bugger what was the question?

    If when radio passively detects a fiber is it the frequency emitted by the light/frequency pulses in the fiber strands or the metallic sheathing ?

    HA!

  14. #14
    Member
    Join Date
    May 2011
    Location
    Nunyabusyknees
    Posts
    63
    Years of Experience
    4
    Rep Power
    9

    Default Re: Radio Mode Questions

    My Rd7000 will pick up metal culverts running under driveways in the rural areas. There is no current on these but it still picks em up. E

  15. #15
    Senior Member UTILQ1's Avatar
    Join Date
    Dec 2011
    Location
    Morgan Cty, Wv
    Posts
    106
    Rep Power
    10

    Default Re: Radio Mode Questions

    Quote Originally Posted by SteveDodds View Post
    My Rd7000 will pick up metal culverts running under driveways in the rural areas. There is no current on these but it still picks em up. E
    There could be a frequency being emitted from another source in the vicinity that you would nt realize...

    If you turn the gain up all the way on a targeted conductor you can start to detect the signal when you are

    100 ft away.

    Same effect can be happening with radio or other frequency on a big ol culvert.

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •