Follow Slashdot blog updates by subscribing to our blog RSS feed


Forgot your password?
Media Technology

PVR-like Software for Audio Streams? 46

JonToycrafter asks: "I'm a dispatcher for a volunteer ambulance corps. We often get our calls by listening to the police scanner. Unfortunately, it's sometimes difficult to understand the street address that the police dispatcher is saying, or sometimes s/he mentions the address before giving an indication that EMS is needed. Does anyone know of a (preferably Free) Windows (or Linux) program that would allow me to connect my scanner to the mic jack on my PC and be able to pause/rewind the stream, a la Tivo?"
This discussion has been archived. No new comments can be posted.

PVR-like Software for Audio Streams?

Comments Filter:
  • by fredrikj ( 629833 ) on Wednesday January 28, 2004 @04:23PM (#8116062) Homepage
    It's useless if you can't fast forward.
  • Is there a reason the VAC couldn't get two-way radios or somesuch from the municipality you dispatch for?
    • Could it be that he is an ambulance chaser instead of an ambulance dispatcher?
      I volunteer as an ambulance driver, and apparently the hardest skill known to 911 dispatchers is that they don't need to eat the microphone when sending a call out. Some are worse than others, but many times we do need to call in for address verification.
    • I would say he is one of the unoffical and unapproved NYC ems units, kind of like Neighborhood watch type setups. I could be wrong, but with his website NYPD does not like him at all. However, he could hook his scanner in the line or mike input and use shoutcast from Nullsoft. People were doing scanner streaming in the mid 90's, so it's not hard.
  • Other solutions (Score:5, Informative)

    by linuxwrangler ( 582055 ) on Wednesday January 28, 2004 @04:34PM (#8116186)
    Don't limit yourself to computer-based solutions. There are devices like this [] for the aviation industry that allow you to replay clearances and instructions. One failing of this particular one is that it stops recording when you are replaying but it's only one of many similar products. Check Google.

    I suspect a clever bit of scripting along with the "record" and "play" programs on linux would do what you want as well.

  • by mcmonkey ( 96054 ) on Wednesday January 28, 2004 @04:48PM (#8116390) Homepage
    When push comes to shove, you could use a TiVo or any of the PVR software for linux or windows. Just run your audio into the PVR and ignore the video.

    You'll probably still need a video display for control purposes, but since you won't need a lot of processing power the whole setup shouldn't cost much.
  • by ivi ( 126837 ) on Wednesday January 28, 2004 @04:51PM (#8116438)
    I find it odd that you guys have to "intercept"
    police radio calls to get your taskings...

    It's standard procedure - in most places - for
    emergency services to ring (a.k.a. "respond")
    EMS or ambulance(s) as required.

    They wouldn't, as a rule, expect the EMS or ambo's
    to spend all their time monitoring other services'
    radio frequencies.

    For one thing, it can increase your levels of
    fatigue (although - admit - it can feel exciting
    to follow incident progress along by radio...
    a bit like armchair quarterbacking, eh? ;-)

    If your service is well & truly needed & respected
    you should be able to get call-outs, just like
    police & firefighters.

    If not, well... raise your game. ;-)
    • Personally, if I'd just been shot and was bleeding all over the place I'd love for someone to intercept the call to the dispatcher and already be on the way by the time the dispatcher noted all the information and called the ambulance. They have to be on alert and they may as well be heading in the direction of a possible call (shots fired, riot, armed robbery in progress) even if emergency services aren't needed.
    • by niko9 ( 315647 ) * on Wednesday January 28, 2004 @08:00PM (#8118920)
      In some states it's called ambulance chasing, even if you are really an ambulance. Medics and EMT's call it "buffing jobs".

      There are many people in (here in NYC) this service that carry their own portable radios that have select frequencies programmed in.

      They listen to both --the EMS dispatcher because they have to-- and NYPD citywide for all the "hot jobs".

      They take it upon themselves to rush to these hot jobs without being dispatched (usually there is another ambulance dispacthed, the closest one as per the EMS dispatch computer), and then tell the dispatcher they were "flagged down" by a bystander. Then they have to cancel the other ambulance, because technically you made patitent contact at that point.

      It's happens daily here in NYC, and you can get into alot of trouble. If your flying lights and sirens to that "hot job" lights and sirens, without being officialy on that assignment --and say-- you hit a bystander, or god forbid a child crossing the street, you can pretty much count on never ever touching another patient in any healthcare field ever again. That doesn't include criminal charges as well.

      You realy should be dispatched by M.A.R.S, mutal aid radio system. The municipal agency overseeing EMS in your county will give your volunteer squad a radio, or maybe just give your dispatcher a ring on the landline phone when they need you. This way everything is documented and copasetic.

      Can your crew still listen to the police frequencies? Sure, if you know how to go about it without anybody getting screwed:

      If you hear some call that you might think is "hot", you can always drive over in non emergency mode and get flagged for the job.

      If you think you have a better ETA than the unit that was assingned, then tell the dispatcher that you are closer. They usually have to give you the call for the benefit of the patient.

      In the end though, you need to change they way your unit(s) get dispatched. Get the chief of the vollie squad to negotiate a M.A.R.S. arrangement. Some vollied even sign out a police radio for the precinct. You'll have to speak to the captain about that arrangement.

      Good Luck, and for God's sake, be careful.

      NYC EMS Paramedic since 1996
    • Wow, what a spectacular way to not answer the question.

      Volunteer EMS and VFDs save people's lives. Pure and simple. It's no time to get into a dick measuring contest. If you can't help answer the question, leave them alone.

    • by The Munger ( 695154 ) on Thursday January 29, 2004 @12:27AM (#8120644) Homepage
      So the story underwent a bit of editing. Here's the original: I'm a seller for a group of drug dealers. We often get our tip-offs by listening to the police scanner. Unfortunately, it's sometimes difficult to understand the street address that the police dispatcher is saying, or sometimes s/he mentions the address before giving an indication that a bust is going to happen. Does anyone know of an alternative early warning system (cheaper than bribing cops) that will help?
  • by _LORAX_ ( 4790 ) on Wednesday January 28, 2004 @04:56PM (#8116519) Homepage
    Have you toug about the possible rammifications of a computer crash, or worse yet say it starts looping on dead air. Would you want to be responsable for the possible loss of life that cound be incured?

    Why compllicate the system when a simple "Could you repeat that address" would probably suffice.
    • Aren't police scanners just one-way radios? Isn't that what the original question was refering to?

      My take was the EMS is simply passively monitoring the police frequencies and responding when needed. I was under the impression that they could not respond. It does sound like a fairly strange setup to me, but I admittedly know jack about EMS / POLICE protocols.
  • LoopRecorder (Score:3, Informative)

    by Figaro ( 20471 ) <> on Wednesday January 28, 2004 @05:46PM (#8117244) Homepage
    Check out

    I haven't used it in a while, but it should allow what you're looking for.
  • The mythtv crew are looking at tivo-like functionality for radio.. Not sure it's exactly what you're after, and I suspect it won't be around for a while.. but it might be a useful starting point for your research:

    Google for 'mythradio'. Here's a starter-link: dev/2002-Octobe r/000753.html
  • Total Recorder (Score:2, Informative)

    by Anonymous Coward There program, Total Recorder, isn't free, but it's not expensive either. I do believe there are some free audio recorders out there now too.
  • Super. (Score:3, Interesting)

    by _aa_ ( 63092 ) <j.uaau@ws> on Wednesday January 28, 2004 @06:56PM (#8118237) Homepage Journal
    Since there seems to be little interest in solving what appears to be a life threatening problem, I will issue a challenge to all developers to make one. This would not be a complex application. In fact the pausing could be done with a simple shell script. I'll start working on a perl one tonight. Please reply with code.

    Whoever replies with the best software Personal Audio Recorder gets a grand slam breakfast at Denny's on me.
    • I solved this problem for my wife a few months ago. She is an avid police scanner listener. She listens every night and sometimes during the day. She calls them her "bed time 'tories" (that's "stories" pronounced like a little kid).

      I split the problem into several pieces.
      1. A standard audio recorder with VOX capability that creates a new file for each sound bite and puts it in a temp folder.
      2. I created a python script called that takes the each file in the temp directory and parses the
  • Explaining the need (Score:5, Informative)

    by Doco ( 53938 ) <Dan@oel k e . com> on Wednesday January 28, 2004 @07:13PM (#8118432)
    If you follow the link to this guys homepage and do a little digging you come across:

    Which state "... active street medic, meaning that during major protests I travel in a squad of medics providing support in the "hot zone", where EMS will not go"

    So - no the cops will probably not help these guys out and they are most definetly not authorized to talk on the police bands.
    • Oh. So he helps stupid people who attack starbucks because they think it will help their cause.

      I say this because those incharge of the protests HURT their cause by allowing idiots to run riot.
  • I know most of the people on the local ambulance team, and all their beepers have a button to replay the last call, and they certainly aren't "cutting edge", if you know what I mean...
  • Denon PVR server (Score:3, Informative)

    by mallocme ( 740799 ) on Wednesday January 28, 2004 @07:23PM (#8118550)
    The denon PVR server will do that
    Denon PVR server []
  • by Anonymous Coward
    But only for FM, and only so far on the ATI AIW 9600 (their only card at this point with an FM tuner.) Does timeshifting great, though.
  • Remember those never ending 15 second tapes used for answering machines? maybe you could use that... 15/30 seconds is alot of time for you to hit play, and listen to the transmission again.
  • Step 1: Connect the headphone/speaker jack from the scanner to the sound card's Microphone port using a standard patch cable.
    Step 2: Plug a set of speakers into the sound card's speaker port
    Step 3: Open Volume Control, and set the Microphone volume (under Playback) to FULL.
    Step 4: Open Sound Recorder, and press record.
    • by Anonymous Coward
      What is the deal with your sig?
      "void main()
      printf "Jorkapp is a Programmer";

      1. Main should return something, not be void. (still functions in most compilers however)
      2. Main should take the amount of arguements, and the arguements themselves. ie: int main ( int argc, char *argv[]). Still functions in a lot of compilers, but incorrect technically.
      3. You got the brackets correct!
      4. Your printf line doesn't compile. It should be printf("jorkapp is obviously *NOT* a programmer";
      5. Recalling main to
  • by neilsly ( 106751 ) <.neil. .at.> on Wednesday January 28, 2004 @08:13PM (#8119031) Homepage Journal
    Why on earth they wouldn't (or wont) give you an actual radio or a pager - is beyond me. There was some mention of an underground sort of medic service earlier, but I can't find mention of that on the homepage he has listed so I won't comment on that.

    You need to get a pager, a Montorola Minitor IV to be exact. These have a dynamic solid state 2 minute memory to replay calls. I would venture to say that nearly every ambulance service and fire department service that is dispatched (or toned, as we say) via radio uses these type of tone pagers.

    Information on the motorola site at
  • Have a look at:

    WiNRADiO Advanced Digital Suite's
    Squelch Controlled Recorder:

    "The recording is conditional on the signal level
    and the receiver squelch setting. The playback
    function also includes the following additional

    Pitch shifting, which provides audio spectrum
    shifting by the specified frequency shift size.

    Variable playback speed, capable of changing the
    speech rate while preserving the pitch.

    Speech inversion, useful fo
  • We have a decent Digital Audio Broadcasting radio network in the UK and I'd love to have it hooked up to my Linux box and a PVR (PRR?) system for:

    replaying snippets

    recording shows to schedule

    keeping the last four hours for when I miss a show.

    V. cool. Now will someone please sell me a DAB PCI card that runs under Linux? All I can find is the following from Modular Technology []:

    Q. Can I use the card under LINUX ?

    A. Modular Technology's stance has to be that in order to maximise the effectiveness

  • Here in Prague we have a managed by city joined dispatching for all services: police, fire and medical rescue both road and air. All dispatchers sit in one room. All called by same number, 112 on mobile services. I can't understand why you cannot have at least a permanent voice line to a police dispatching. Such a facility was available here even in WW2, under the german occupation, 60 years ago. Police dispatcher should be talking with you what's needed. Or, are you a bunch on illegal kidney stealers?
  • First of all, a solution.

    RecAll [] from Sagebrush can do nearly everything you need. It is a small, free, and easy to use VOX line-in recorder for Windows, and is popular for scanner monitoring.

    It includes a feature where it can start a brand new wave file after a set number of seconds of silence. So basically it would create a separate audio file for each individual radio transmission (more or less).

    You could then play that wav file in any audio player (like soundrec or winamp), while RecAll keeps happily

One good suit is worth a thousand resumes.