Decoding Fire & Ambulance MDT data & hospital pages with a $10 SDR Radio

[@R33f4_61]

Great video... had it up and running in no time. Found 2 systems just above the 2m band. POCSAG/512(Hosp.) & FLEX/1600(Em Serv.)🇦🇺

[@FrugalRadio]

Excellent. Well done. What area are you in?

[@R33f4_61]

@@FrugalRadio I'm in Sth Aust. I was hoping to be able to get mdt job dispatch data for emergency services but i haven't had any luck in finding that yet. Not sure it's even possible anymore bcos of newer systems, and encryption ??? (Just getting back into the hobby after a 5yr break)

[@FrugalRadio]

There are many ways to send such data now. Some departments use cellular data links, some have their own data link systems, some send data via their P25 system, some use pages, and many are now switching to smartphone & tablet apps.

[@R33f4_61]

@@FrugalRadio There's a local website that has 800Mhz & 1800Mhz RDLAP data frequencies listed but i don't pick up any signals in the 800's. Obsolete??? And I've noticed that police vehicles now have a small thick antennas(about 4inches) so I'm thinking that's probably for a separate data system🤔

[@R33f4_61]

@@FrugalRadio One other thing... how do i go about creating a FMP ScanList ???🤔🤔🤔 I've watched many videos, including yours on sdr# & dsd+, but I'm stuck on that part. The videos I've watched only say to download one from RR which isn't possible. Help in the right direction would be much appreciated.

[@jj2me]

Great video Rob! Thanks for the useful tips on decoding those signals, I've often wondered. Nice seeing you back up and running again too.

[@FrugalRadio]

Thanks! Let me know what you're able to decode if you decide to give it a try!

[@ManuelPinner]

SDR Angel have this Feature available on it!

[@CptnKremmen]

Many (20ish) years ago I wired a jack socket to the discriminator on my AR2000 scanner. It's nice to know that SDRs can use a similar trick. I didn't realise that people were still using pagers - I might have to dust if off and use the PDW software (just checked my NAS) I used to use POCSAG Decoder.

[@FrugalRadio]

Yes, what you will receive will depend on what's in use in your area. But SDRs are way easier than discriminator taps!

[@SignalsEverywhere]

Thank you for mentioning and linking to my tutorial, love your channel. Great production value, I like how you put your videos together!

[@FrugalRadio]

Thanks @SignalsEverywhere. Your channel is part of the reason I got started!

[@-_______________________.___]

@@FrugalRadio Sadly she quit KZbin 2 days ago :'(

[@FrugalRadio]

Oh, I didn't know this.

[@Ztbmrc1]

Nice video. Interesting what you can still see there in Edmonton, Canada. Here in the Netherlands we have strickt privacy legacy. Besides that the services of fire, ambulance and police changed over to the digital tetra based system (C2000) for their voice communication that we can no longer listen to, they still have a pager network operational (P2000) on 169.65 MHz in Flex 1600 mode. But they are reducing the information there also because of the privacy rules. The police has stopped using the pager system, however they remained sending press messages there. But recently they have decided to stop that too. Btw I just discovered another weaker pager signal next to the P2000 on 169.625. It were messages first in French than also in Dutch. They are from Belgium. It looks like hospital and ambulance services. Did not know about that... It is in POCSAG 2400

[@FrugalRadio]

Thanks for your report on the state of transmissions in NL. Cool that you can receive the Belgian pager signal too. I was traveling in the UK last month. Still saw some Ambulance traffic on the pager networks, as well as general medical info.

[@Ztbmrc1]

@@FrugalRadio Ok. I just found the confirmation that indeed on 169.625 is the Astrid pager system from Belgium. And alle other public pager systems have ceased to exist here in the Netherlands. Just wonder where the hospital pagers here in NL are...

[@djk8541]

I like that your videos open with background information to explain why we may be interested in following the guide

[@FrugalRadio]

Good to know that's helpful, thanks.

[@someoneintheback5939]

Awesome video! Great tutorial! Been wanting to do this with my rtl for a while!

[@FrugalRadio]

Have fun giving it a go!

[@Subgunman]

Some places still use the older Motorola Golay format. There were paging programs one could load onto older computers but utilized modem cards to dial into the paging transmitters over dedicated DID ( direct inward dialing ) inbound lines to the paging terminals. User could bring up the program and send a page, numeric or alpha, to the specific user.

[@EverydayJ1786]

Very cool Rob ! . I was not aware of the ability to monitor pager signals in the Edmonton Area 👍

[@FrugalRadio]

Yep, there's loads of data traveling through the air all around us!

[@MrToymod]

Thankyou Rob , got me up and running, you are a star **. I’ve bought you a coffee as you’ve saved me lots of frustration 😅

[@FrugalRadio]

Appreciate it. Thank you!

[@skideric]

Have done this off & on for years.Mostly with Scanner & PDW Software,easier than using dongle...

[@FrugalRadio]

My first attempts were with scanners, years before SDRs were so ubiquitous. However I don't like tying up a physical radio when I can use an old SDR that would otherwise be lying around in a drawer! What frequencies & modes are used in your area?

[@coondogtheman]

I was able to get this working ok with nothing more than my computer, PDW program and a wind up radio that can pick up weather bands and somehow picks up pager traffic. I have an RTL SDR but the reception is crap when I have it hooked to my PC so I use my phone for the SDR with SDR touch and it works well. Can't use that for the pager traffic though. The data I hear sounds just like some of the transmissions heard in the video.

[@FrugalRadio]

Very interesting. Pager transmitters can be very strong, so they often decode well - but this is the first I've heard of it on a wind up weather radio. That's neat. Thanks for sharing!

[@coondogtheman]

@@FrugalRadio I don't know where the radio is at the moment but it has this reverse phase simulated stereo which messes up the signal but if I pull the cord out slightly it works. I may have to modify the radio of better yet find another that works.

[@TheRifleman336]

Sadly since the mid 1990s it's been illegal to decode Pagers, or MDTs for public service here in the US. Get caught and it's either a heavy fine or prison time..... :(

[@FrugalRadio]

That is unfortunate indeed.

[@williamhowell1791]

What state do you live in that says this law is true law.... I'm not aware of a FCC rule that states such... It's only illegal to monitor such traffic if one uses it for money gain... or in some states if it's encrypted. Othen than that, the airwaves are open to anyone that wants to listen to them..

[@FrugalRadio]

I'm in Canada, and I think it is okay to monitor here. But in the UK where I lived for 30 years, you are not allowed to monitor any signals not intended for you.

[@kishascape]

​@@williamhowell1791it's not actually enforced. I used to Livestream decoding all the time years ago and would post the PDW logs online publicly.

[@thewind-ne8rh]

welcome back

[@FrugalRadio]

Thanks!

[@lizzapaolia959]

Fantastic video, God bless 🙏

[@FrugalRadio]

Thank you! You too!

[@sekyuvlog]

Nice video, I learn a lot on your video.

[@FrugalRadio]

Great. Glad it has been helpful.

[@BenjiNotknown]

I have both POCSAG & FLEX here in England, FLEX is much more rare toreceive a message though. I didn't know there was a voice pager frequency though, i'll have to tray that. thanks.

[@FrugalRadio]

Keep an eye on the waveform in your SDR software. The voice pages are transmitted in amongst all the data. If you have audio routing to PDW you'll often miss it. Sometimes I set a scanner to the pager freq to monitor the voice traffic, but it's frustrating as most of the time you just hear the sound of the data.

[@Lordabememes]

Can you please make a video about Tetra trunk tracker software and The Tetra demodulator

[@FrugalRadio]

No, unfortunately I can't. As I'm in North America I have no Tetra systems in use in my area.

[@Lordabememes]

@@FrugalRadio Ah ok I understand thank you anyway I really enjoy watching your videos

[@robertodelavega9311]

o tetra e outro plugin. não usa cabo virtual se não estiver criptografado e fácil.

[@tomrous]

Quetion for viewers: Is there any pager system commonly used in Europe?

[@FrugalRadio]

I received both POCSAG & Flex in Europe in 2019. What about other users? As Tom asked, what systems are you picking up?

[@cmjx]

I receive local pager traffic on FLEX at ~929mhz, and POCSAG at 1200baud - 152.0075 MHz. The latter is less intrusive information. I usually just run: "multimon-ng -a POCSAG512 -a POCSAG1200 -a POCSAG2400 -a FLEX -f alpha" while having SDR++ running to get output in a terminal.

[@FrugalRadio]

Sounds like you've got it well figured out for your area. That's great. Thanks for sharing.

[@cmjx]

@@FrugalRadio It's a great video, thanks Frugal Radio!

[@FrugalRadio]

Thanks for your kind comments 😃

[@dilushasamarasekara9533]

Great video as always...!!!

[@FrugalRadio]

Thank you 😊

[@jamesbrady9105]

I set up the Sofware and appears to be working, but I cant decode any signals, even though I can see signals in SDR. I live in Richmond, Virginia and there are a lot of hospitals in the area, so I should be able to pick up and decode something?

[@FrugalRadio]

A first step would be to identify that the signals you are receiving are indeed pages. Have a listen to the various protocols on sigwiki.

[@morejelloplease]

can sdrtrunk do this without having to download the extra decoding program and virtual cable ?

[@kenny7479]

Great video. I was curious if you had tips on getting a better percentage reading on the top right of PDW? My reading seems to be somewhere around 70 and red.

[@FrugalRadio]

Hi Kenny. Playing with the audio levels is the key, and making sure your bandwidth is wide enough. There are times I really struggled to get the balance right, especially on certain computers. Other times it works perfectly. A lot of trial & error!

[@RedLine_Renesis]

Remember folks. You could be decoding the last moments of someone's life. You will, one way or another, be part of it.

[@FrugalRadio]

Certainly a possibility. Although a high percentage of fire service calls are also false alarms!

[@williamhowell1791]

So what's your point??

[@LTtaz4067]

I live in the US, my counties public safty is on P25 band. Your video above is assume and I can't wait to try it. I have a question about video feed. My services send images of things like EKG's (ECG's) over the radio. What do you need to be able to see those?

[@FrugalRadio]

I'm not sure. A lot of agencies would send that sort of data by either cellular, or PoC. Here law enforcement distributes images by a secure app on their phones.

[@LTtaz4067]

@@FrugalRadio thank you

[@alanwallis2796]

Hi Rob, thanks for the video, just a quick question, I see you are using SDR ++ do you know of any conflict problems when using the SDR Sharp and SDR Sharp community package with SDR ++ Installed ? I think I saw a post somewhere that the early versions of SDR ++ caused problems ? and SDR Sharp had to be re installed ? It may be that the latest release has solved that problem any thoughts regards Alan

[@FrugalRadio]

Hi Alan. I hadn't heard anything about that. I have SDR# (an older version) and SDR++ installed on the old laptop that I used to make this video, and didn't encounter any problems. Although I only used SDR# once since installing SDR++.

[@ManuelPinner]

SDR Angel Software can do this to!

[@FrugalRadio]

It can decode POCSAG, yes. Can it also do the filtering?

[@gage3809]

I am tuning into the same frequency since it is fairly active, and it seems that the audio cable is working since in PDW the needle jumps around during broadcasting (not by much though), but there is nothing showing up....any ideas why?

[@FrugalRadio]

There are a lot of things to check, but they are all covered in the video I think. Make sure your check the first part on how I set up the software. Ensure you're using NFM with a bandwidth similar to what's shown. Also, play around with your volume settings. PDW can be quite finicky when it comes to this. You might want to experiment with your gain levels as well.

[@BritishBeachcomber]

You can't do that in the UK, where we've been using digital radio, similar to the cellphone network, since 2000.

[@FrugalRadio]

Actually you can. Several ambulance services are still using pagers for MDT transmission.

[@BritishBeachcomber]

@@FrugalRadio True, but pagers don't carry much useful information, just alerts.

[@MrToymod]

@@BritishBeachcomberI’ve just had a go in the uk , interesting stuff!!.

[@FrugalRadio]

Yes, surprising what is out there.

[@AntonioFardella]

I have a question. I have been told that that 243.000 and 282.8 MHz are emergency frequencies. On paper they should belong to VHF spectrum, but they appear to be the "UHF emergency frequencies". Why is that? Why are they listed in the set of UHF while they evidently belong to VHF spectrum? Thank you for your answer.

[@FrugalRadio]

The 225-399 MHz range is dedicated to Military Airband frequencies in some countries. Other countries it's up to 380 MHz. This has come to be known as the UHF airband, since the largest part is UHF. You make a good point though. Technically almost half is VHF. But VHF air frequencies is used to refer to the civilian airband (118-136.975).

[@AntonioFardella]

@@FrugalRadio Thank you for the fast reply. At this point I put aside the mere meaning of "VHF spectrum" and "UHF spectrum" and will rather consider "spectrum for civilian use" and "spectrum for military use". Precious info!!

[@bennguyen1313]

Does the Pager decoding software (SDRPlusPLus/PDW) only do POCSAG , FLEX , AUDIO? Or can it be configured for other public/emergency broadcasts like P25/ DSD (LouisErigHere)? For example, I understand for the Inmarsat AERO satellite (1600Mhz) which covers C Channel for air to ground and L-band for ground to air. Medlink voice communications uses (Iridium?) decoding? I believe jontio / libaeroambe built JAERO to decode AMBE compressed audio, but not sure.

[@FrugalRadio]

PDW can do POCSAG, FLEX and ACARS officially. I've used it only for the first 2 of those. It cannot decode satellite ACARS. For that you definitely want JAERO with AMBE if you want the audio.

[@bennguyen1313]

@@FrugalRadio Thanks. I've heard OpenEar also shows promise of an all-in-one decoder (TETRA, P25, POCSAG, ADSB, AM, N/WFM)!

[@FrugalRadio]

Yes, although it can no longer be directly downloaded. I gave it a try, but had greater success with other software.

[@MrShiffles]

anyone having issues with vb-cable in windows 11? I cant pipe any audio into pdw or dsdplus etc

[@LTtaz4067]

Hi Frugal, I have gotten to a point in this sdr journey I have another guesting. I the video about pager, you talk about MDT terminals. I gave to three software I am using at the moment, SDR#, DSD++ Fastlane, and SDR - Trunk. They all are decoding what looks like the information from the MDT, but it goes by really fast. My question is how did you make the pretty monitor to look like a real dispatcher terminal.

[@FrugalRadio]

Hi Chris, thanks for your question. I don't get any MDT type data on the P25 system here as it is all encrypted. I can see data transmissions taking place, but no data from them. Not even GPS coordinates. My pager screen is generated by PDW, a free POCSAG / FLEX decoder available online. I use it's filtering capability to display the traffic I'm most interested in on the bottom pane. The top pane shows all the other traffic passing through the system (mainly hospital stuff).

[@LTtaz4067]

@@FrugalRadio I have been having a hard time getting it to work. I set SDR# audio to VRW line out. My PC's is VRW line out, and PDW software to VRW line out. I have played with different volume settings and nothing runs, just loads up. Any ideas.

[@FrugalRadio]

If the needle in PDW moves, then it is receiving audio. If the needle doesn't move, no audio is getting through. That's the first thing to check. Then you can check levels. It is also good to check on the parameters of SDR#. Is your bandwidth set to a good value (just beyond the edges of the visible pager signal)? Is the RF gain appropriate? Is it a good, clean signal when you listen through the speakers? Then in PDW ensure that the correct signal format is selected for decode, based on the signal you're receiving. For example if it is set to ACARS, it might not decode pager traffic. Ensure the appropriate baud rates are selected as well. I usually check all the options for that, as some transmitters use multiple baud rates based on the subscriber device.

[@LTtaz4067]

@@FrugalRadio Thank you than was very helpful I will try this.

[@dennisbaker555]

I noticed when you entered your receiving frequency that it was one single frequency. I know little to nothing about decoding paging, but I am curious. In my area public safety uses a trunked network, specifically P25 Phase I and P25 Phase II. I would assume that the digital information is sent out on one of the control channels within the trunking network. So, does this device you featured have the ability to monitor multiple frequencies? How would you go about decoding paging on a trunked network?

[@FrugalRadio]

Data traffic on P25 networks seems to use regular channel assignments on the network. I honestly don't know a way to decode that data. I would assume it is also encrypted.

[@dennisbaker555]

@@FrugalRadio ok, I’m going to see if I can figure it out. I’m sure there is stand alone trunk tracking software. My assumption is that if voice isn’t encrypted then data won’t be either. But, I could be wrong.

[@FrugalRadio]

If you are familiar with wireshark, that might be a place to start. SDRTrunk appears to show IP addresses of data connections.

[@Domgelina]

How come I can't install the slicer driver, it needs a specfic comport nothing works?

[@FrugalRadio]

No idea. I didn't install any slicers. Just ran the audio via virtual cable. No need for discriminator taps or slicers when using SDRs 🙂

[@Domgelina]

@@FrugalRadio I got it working now, just had to figure, out my local freq

[@FrugalRadio]

Excellent news. Perseverance pays off What services are using it in your area, and what frequency are you finding signals on?

[@Domgelina]

@@FrugalRadio I'm in Ontario 4 hours away fom Toronto, so far i just found one freq- in the 929's, but its from toronto hositpals-- the type says mostly Alpha

[@Domgelina]

Is their an esier way to look for freq, i have the ranges i need on paper

[@ManuelPinner]

Sdr Angel Software have this Feature,

[@FrugalRadio]

Yes it does. Can it also filter the specific messages you want to see, based on keywords and / or capcodes?

[@Onkel_Daniel]

Thanks for the video, but it's nothing for me, our Pocsag is encrypted 😭

[@FrugalRadio]

Oh, that's a shame. I see some encrypted pages, but they are few and far between. Do you have any idea who the users are, and what frequency / area?

[@Onkel_Daniel]

@@FrugalRadio German Fire and EMS.. some between 164 and 179 mhz and some around 380-430mhz

[@FrugalRadio]

Thanks for letting me know @Faolan. It is interesting to hear about the different frequencies and users in each region.

[@Onkel_Daniel]

@@FrugalRadio im work with SDR since 2016 i mean.. its very nice but the Most frequencies are encrypted, new we have Tetra POL and in a few month we get encrypted Pocsag :( xD

[@David-wv7sv]

Terrible Audio, Invest in a cheap mic at least.

[@min55r]

Hola, como puedo contactar con usted ? me gustaría poder preguntarle sobre un programa...el precio y como funcionaria...Gracias (soy española traduje este escrito para poder comunicarme con usted) Hello, how can I contact you? I would like to be able to ask you about a program... the price and how it would work... Thank you (I am Spanish, I translated this writing to be able to communicate with you)

[@JoeProsser1]

Hey.. just got my sdr today... what luck... looking forward to learning.... N9QHF

[@FrugalRadio]

Best wishes with the experimenting! 73!

[@wucathy24]

Hii, great vids! We would like to collaborate with you, is there any contact?

[@FrugalRadio]

Who are you and what would you like to collaborate on?