Scanning Q&A

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Revision as of 13:36, 7 July 2008 by Ka3jjz (talk | contribs)

This article can be used to house questions about scanning in general - anything from antennas to laws to coax and more


On the Radio Reference Database, there are some terms used that may be unfamiliar to the new scanner user and some data that you don’t need. Most of the time, if you mouse over the column heading in the database, you will get the answer to your question. If this doesn't work, please see our Glossary article.

  • ''I see two frequencies for the agency I want to monitor, which one do I put in my scanner?''
    • This would indicate one of two things in the RR Database.
      • If the channel is listed with a R in the Type column, then just program one in the Frequency column.
      • If the channel is listed with a B or BM in the Type column, then you really need to program both, as this would indicate this is a Duplex channel, where normally the base station will be on the frequency designated in the Frequency column and the mobile will be on the frequency in the Input column.
  • ''There is a column called Tone and it has funny numbers in it, do I need to worry about this?''
    • It all depends. What those are, are CTCSS and DCS values. If your scanner can accept them it will reduce outside interference from what you are interested in hearing. This means the agency you are programming uses that tone (or code) to limit reception/interference from other agencies that may be licensed on that frequency. Some scanners cannot use these tones and some agencies do not use them either. It really comes down to a personal choice on your part.

General Scanning Questions

Equipment Questions

  • ''Where can I find information on scanner antennas, filters, mobile mounts, ect.?''
    • Return to our main page via the navigation link to the left, go to the bottom and see the 'Antennas and Accessories' category.
  • ''I want to hear more. Will an amplifier help?''
    • Before you go looking at amps, make sure that your antenna and feedline are at the best you can afford. A nice high antenna, with the right coax, will hear lots - maybe, at times, too much. In some cases, a good filter will be a huge asset. Not all scanners - particularly handhelds - work very well with big outdoor antennas and feedlines. They simply aren't designed to handle that much RF all at once.
  • ''Is the coax that important?''
    • They can make the difference between hearing a signal (particularly if you are out in a fringe area) and not hearing well, or at all. The larger the loss, the less signal is received. The general rule is a 3db loss results in a loss of 1/2 the signal. In practical terms, if you are in a strong signal area, this won't mean much - but if you're a long way off, this kind of loss should concern you. These links explain this clearly;
    • Strong Signals Coax Cable
    • NASA Coax Cable loss chart
    • Coax Line Loss Calculator
  • ''How do I program my scanner from the PC? How do I find compatible software?''

General Frequencies

If you are searching for specific frequencies in your area, the RR Database is the place to start - but at times there may be a better option....

  • ''Where can I find frequencies for the various services, such as Railroads, Aircraft, ect.?''
  • ''Where can I find frequencies for NASCAR, LPGA, NFL, ect.?''
    • See our Sports frequencies article
  • ''Im flying into an airport that the RRDB doesnt have. Where can I find frequencies for it?''
    • Go to the popular Airnav website
  • ''Im going on a cruise and would like to see if theres activity to be heard. Where can I find frequencies?''
    • See this popular website by Bill Dunn for cruise ship frequencies
  • ''I need to look up a callsign I copied. Where can I find it?''
  • ''I need to look up a frequency that isnt in the database. Where might I find it?''
  • ''Where can I find out about military communications in my area?''
  • ''Where can I find out about frequencies used by the US Federal Government?''
    • Check out our Federal frequencies article