Difference between revisions of "Scanning Q&A"

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* '''''''What is this rebanding I keep hearing about? Will my scanner still work after this happens?'''''''  
* '''''''What is this rebanding I keep hearing about? Will my scanner still work after this happens?'''''''  
**The answer to this is pretty involved, see the excellent special topic [[Rebanding]] article.
**The answer to this is pretty involved, see the excellent special topic [[Rebanding]] article.
=== Interpreting Database Entries===
====Conventional Topics====
*'''''''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.
****See [[Repeater]], [[Output frequency]], and [[Input frequency]] for further details.
***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.
====Trunking Topics====
* '''''''I am trying to monitor a trunked system in my area. I have a (insert model) and all I hear is noise. What's wrong?'''''''
**You may be listening to the data on the [[Control channel]] as audio.  The system must be programmed as a [[Trunking Basics|trunked]] system.  Your scanner must support trunked system monitoring.  See [[:Category:Trunking_Scanners|this category page]] to see the scanners that can monitor trunked systems.
**The system may be transmitting digitally-encoded audio.. Check the [ database] for your area to be certain. The only scanners on the market that can receive ''non-encrypted'' digitally-encoded audio are those listed on [[:Category:Digital_Scanners|this category page]].
*'''''''On the trunking talk group display, I see DEC and HEX, which one do I use?'''''''
**For [[Motorola]] and [[Project 25]] (APCO-25) systems, all trunk tracking scanners accept what is known as the '''Uniden Decimal''' format, that is the '''DEC''' number you see in the [[Talkgroup]] display.  The '''HEX''' number is the actual Motorola Talk Group equivalent of that number as a hexadecimal. Professional radios (such as Motorola handhelds) and the newer GRE [[PSR-500]] and [[PSR-600]] scanners can use them, but other scanners can't. There is a correlation between the two, but this correlation is different depending on the system being looked at.  Some systems use a different format all together such as the [[Logic Trunked Radio|LTR]] systems (system-home repeater-talk group) x-xx-xxx format or the [[EDACS]] AFS (Agency – Fleet – Sub-fleet)
*'''''''On the trunking talk group display, what does the mode mean?'''''''
**Each talk group in a trunking radio system may broadcast in many modes, the mode most often found for a particular talk group is displayed in this column.  If you '''mouse over''' the column heading you will see the various codes used in the column and what they mean.
*'''''''On the trunking system I am trying to program, some of the frequencies listed are red or blue and have an asterisk next to them, what does that mean?'''''''
*'''''''What does the 'c' or 'a' in the frequency listing indicate?'''''''
**The red and blue frequencies are those identified as the control channel (CCh (in red with a 'c')) or alternates (in blue with an 'a'). 
**Now comes the confusion, if the system you are looking at is a Motorola or a Project-25 system and your scanner is capable of [[Control Channel Only]] trunk tracking then you really need to only program the CCh and alternates for it to work. 
**If you are programming an EDACS or LTR system, then you must use all of the frequencies listed and put them in the correct order and in the correct position in your scanner.  Some scanners ask for the LCN ([[Logical Channel Number]]) when programming these systems and others rely on you placing them in the correct bank position on your own. 
***If you look carefully at the frequency display you will see these types of systems have a small number to the left of the frequency, which is the LCN of that frequency.  For example, if you were programming an EDACS system in bank 2 of a Pro-97 scanner, then you would put the frequency for LCN 1 in bank position 201, LCN 2 in position 202, and so on. 
**Note, in both EDACS and LTR systems, not all positions may be filled and there is no rule about skipping slots, so a site may start on LCN 4, which you program (again using the above example) in bank position 204, and go on from there.  If you are told to start at bank position 1 in a bank, that is only correct if there is an LCN 1.
*'''''''How do I tell if a system is to be programmed as a Project 25 system?'''''''
**Examine the '''system voice''' as listed in the database. Those entries that say ''System Voice: Analog and APCO-25 Common Air Interface'' are not true Project 25 systems, as they have one or more analog talkgroups. Program these systems as a Motorola system, and let the scanner detect the digital. If the System Voice says ''System Voice: APCO-25 Common Air Interface Exclusive'' then this system is a true Project 25 system. In both cases, a [[:Category:Digital Scanners|Digital Trunktracker]] is required to fully copy these systems, assuming none of the talkgroup entries are marked with 'E'. These are encrypted, and no scanner will copy them.
* '''''''The database says that my area uses [[EDACS Provoice]] (or EDACS [[OpenSky]] ). Can any scanner receive these formats?''''''' Due to the proprietary nature of these formats, no scanner can receive either of these formats. There are several such formats which scanners cannot track (or receive); the most common ones are listed at the bottom of [ this page]
=== Equipment Questions===
=== Equipment Questions===

Revision as of 16:01, 7 July 2008

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.

  • ''What is this rebanding I keep hearing about? Will my scanner still work after this happens?''
    • The answer to this is pretty involved, see the excellent special topic Rebanding article.

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?''
  • ''Where can I find downloadable files/data for my scanner and area?''
  • ''How do I connect my line out/headphone/speaker to the soundcard on my PC? How do I find compatible software?''
  • ''I've connected my scanner to the soundcard on my PC. Why dont I hear any audio?''
  • ''I want to record and log audio from my scanner. What do I need to make this happen?''
    • See our Connecting Radios to Soundcards article. There are a series of links at the bottom of the article for various types of soundcard-driven software as well as scanner software that has the capability to log and record. Note that most Radio Shack scanners cannot perform this function - it's not possible since it's a function not provided for in the firmware. You can use a package such as RecAll or ScanCorder to record audio while sitting on a single channel. The old Pro-2052 is the lone exception.

General Scanning Questions

Frequency Searches

If you are searching for specific frequencies in your area, the RR Database is the place to start - but sometimes 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