RTL-SDR# + PDW Decoding issues

If your into decoding transmissions, this is the place for you. Topics cover everything from pocsag, ermes, acars, flex & mobitex!!!
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Phantom
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RTL-SDR# + PDW Decoding issues

Post by Phantom » Sat Apr 18, 2015 9:57 pm

True! These systems work ideally with un-deemph audio!
He might just have better success with a FSK than his current settings resulting in 50-60%

The reason it starts out close to 100% as, like most percentages, it has to wait for a larger total to pass thru the system to give a more accurate and true representation. The reason it ends up closer to 50-60% is that it would only be decoding 50-60% of the TOTAL messages that pass thru the system.
Sourcing the un-deemph audio from the radio will greatly improve this result, and in turn your decoded messages on the screen.

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Re: RTL-SDR# + PDW Decoding issues

Post by turbine_prop » Sat Apr 18, 2015 11:15 pm

certsol wrote:Not using discriminator tap, I can't retrofit one into this laptop. The setup is a really good 2m base antenna on the roof into a uniden bearcat scanner, then line into the microphone inlet on the computer. I had to stuff around with the volume settings a lot to get it to hear anything. if i restart the computer it usually decodes at 100% +/- 5% for a short time and then gradually goes down to around 50- 60%. I'm only tapping into 148.5875 to push the fire call pagers out to mobile phones. I pick up a reasonably good range, several hundered kms. Some days I'll pick up 3or4 of the same pager messages fine, i.e from different towers, other days I'll get 1 with a second one truncated

Would you mind elaborating on how you are pushing the fire call pagers out to mobile phones. Please.

Regards
Wayne
Melbourne.
Regards
Wayne
Melbourne

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Phantom
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Re: RTL-SDR# + PDW Decoding issues

Post by Phantom » Sun Apr 19, 2015 8:00 am

Have a search thru the forum Wayne. Was covered a few years ago I believe.

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Re: RTL-SDR# + PDW Decoding issues

Post by certsol » Sun Apr 19, 2015 5:32 pm

Than you. I'll read up on those options. and give it a go :-)

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Re: RTL-SDR# + PDW Decoding issues

Post by certsol » Sun Apr 19, 2015 5:38 pm

turbine_prop I've got twoset ups, one is software written by Gerard Dunning that pushes through myrfscrew.com the other is a little program written by a guy in Lugano RFS that hooks into the PDW logfile and sends filtered messages, both into a pushover app called eNotify and SMS, I'm using smsbroadcast for the sms push

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Re: RTL-SDR# + PDW Decoding issues

Post by Phantom » Sun Apr 19, 2015 5:38 pm

By all means, if you have questions, be sure to ask them as there are MANY people on here that have vast and varied experience with PDW and I am sure you will be able to get it operational - through shared experience

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Re: RTL-SDR# + PDW Decoding issues

Post by certsol » Sun Apr 19, 2015 6:17 pm

Can the FSK and discriminator be fitted at the scanner end and then fed into the computer microphone jack of the computer?

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RTL-SDR# + PDW Decoding issues

Post by Phantom » Sun Apr 19, 2015 6:25 pm

You need to read up on it! It's all explained there. I sent you a few links, read thru them and you should find the info you need. If you still have questions, then ask away for clarification :)

As you read, you will see that the discriminator audio ONLY comes from the scanner. Once you have that fitted to the scanner, the sources audio can then be fed into the computer sound card. Don't worry about FSK just yet. Focus on finding the un-deemph audio out of the scanner and into the sound card. This should help your decode rate considerably.

If we know the scanner you have, it may be easier to help point you in the right direction if you are having problems.
Maybe start a separate topic to keep this topic on track, as the original question relates to SDR

certsol
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Re: RTL-SDR# + PDW Decoding issues

Post by certsol » Sun Apr 19, 2015 8:11 pm

Thanks, I went down a buch of rabbit holes when I was reseaching and they were talking about modifications in the computer :shock: and I asked myself wouldn't it be easier to do the job on the scanner side...which as you say that's the way to go. I also bumped into another post in here posted below for others who might benefit i.e me who is all thumbs with soldering irons :oops:

[quote="wesky"]G'day Guys,

Just giving you all a heads up, especially for those that aren't in the loop / aware - like I was.

For those wanting to decode pager messages, you probably have heard of a discriminator tap, looked at how to do one and then had kittens - just like me!

WELL, there is a way you can get a quality tap put in by someone who is reliable, quick and definitely in 'the know' of these things.

Check out Dave @ http://www.scannerantennasplitter.com & on scannerantennasplitter at westnet com au.

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RTL-SDR# + PDW Decoding issues

Post by Phantom » Sun Apr 19, 2015 8:46 pm

He is a member on here, look him up and he will certainly be able to assist you.

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Re: RTL-SDR# + PDW Decoding issues

Post by Boort8720 » Sun Oct 11, 2015 9:59 am

I am having many issues too. Any help would be much appreciated.

I am not sure whether I have a signal issue or a sound settings issue. When a message comes through I can hear the tones, but it is almost completely overpowered by static. (It's really bad quality audio)

In PDW the needle flickers but it can't pick up the tones (Running through VB Cable) which is obviously because the audio is really bad.

If anyone has any ideas please share them with me

Thanks, Mitch
Mitch Baker

Uniden UBCD396XT, BCT15X, UBCD996T, UBCD436-PT, Tait TM9100, Simoco SRM9000, Yaesu FT70D, Motorola GP339

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Re: RTL-SDR# + PDW Decoding issues

Post by cfa4x4 » Sun Oct 11, 2015 10:17 am

If the sound sounds the same quality through the scanner speaker and the pc speaker, it would be your scanner. (Maybe a better antenna outside may help)

PDW is very fiddly with the volume control

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Re: RTL-SDR# + PDW Decoding issues

Post by melbournefan » Sun Oct 11, 2015 12:50 pm

I think if you change the record freq to 4500hz it might fix it will check when I get home

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Re: RTL-SDR# + PDW Decoding issues

Post by Boort8720 » Mon Oct 12, 2015 6:26 am

It definitely isn't the same quality as my scanner, I've tried using a scanner but that didn't work very well. I'm using and RTL SDR Dongle.
Mitch Baker

Uniden UBCD396XT, BCT15X, UBCD996T, UBCD436-PT, Tait TM9100, Simoco SRM9000, Yaesu FT70D, Motorola GP339

chainz
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Re: RTL-SDR# + PDW Decoding issues

Post by chainz » Mon Oct 12, 2015 1:52 pm

Make sure your dongle is calibrated correctly and don't use squelch. I use the same setup with no issues and 100 percent decode.

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Re: RTL-SDR# + PDW Decoding issues

Post by Boort8720 » Fri Oct 16, 2015 9:47 pm

Thanks Chainz,

I don't use squelch anyway, but I will try and calibrate it

Thanks,
Mitch
Mitch Baker

Uniden UBCD396XT, BCT15X, UBCD996T, UBCD436-PT, Tait TM9100, Simoco SRM9000, Yaesu FT70D, Motorola GP339

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Re: RTL-SDR# + PDW Decoding issues

Post by Boort8720 » Thu Oct 22, 2015 6:29 pm

Thanks for everyone's help. I am now decoding through SDR# at 100%. A big thanks to chainz, who helped me get up and running :D
Mitch Baker

Uniden UBCD396XT, BCT15X, UBCD996T, UBCD436-PT, Tait TM9100, Simoco SRM9000, Yaesu FT70D, Motorola GP339

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Re: RTL-SDR# + PDW Decoding issues

Post by slothking » Mon Jun 13, 2016 9:43 pm

Hi guys. I recently got myself an Rtl-sdr and have been playing around with SDR# and Pwd. I have calibrated my unit using the local ATIS message (It surprisingly didn't need any calibrating?). I have listened to the pager sounds using my 369xt and compared it to the sounds out of my PC and it Sounds loud and clear. I have installed the virtual audio cable and have tried with different volume levels. I have tried to mirror the settings shown elsewhere on this page but it hasn't seemed to have helped. Has anyone got any magical hints? I'm located in Tas so don't have many channels to play with


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Boort8720
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Re: RTL-SDR# + PDW Decoding issues

Post by Boort8720 » Sat Sep 24, 2016 10:01 am

Hi all,

Has anyone recently discovered that PDW will not decode anymore? I have SDR# set up and outputting crystal clear POCSAG signals. The signal indicator needle in PDW is flickering, but when a message comes through it will just keep flickering. Could it be PDW, VB-Cable or SDR#?

Any ideas much appreciated, Thanks in advance.

-Mitch
Mitch Baker

Uniden UBCD396XT, BCT15X, UBCD996T, UBCD436-PT, Tait TM9100, Simoco SRM9000, Yaesu FT70D, Motorola GP339

Boort8720
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Re: RTL-SDR# + PDW Decoding issues

Post by Boort8720 » Sat Sep 24, 2016 10:50 am

Boort8720 wrote:Has anyone recently discovered that PDW will not decode anymore? I have SDR# set up and outputting crystal clear POCSAG signals. The signal indicator needle in PDW is flickering, but when a message comes through it will just keep flickering. Could it be PDW, VB-Cable or SDR#?
Apologies to everyone....

I went back to square one and found that most of the basic settings were all over the shop. It's amazing what you can achieve when you slow down and think about whats going on.

Thanks

-Mitch
Mitch Baker

Uniden UBCD396XT, BCT15X, UBCD996T, UBCD436-PT, Tait TM9100, Simoco SRM9000, Yaesu FT70D, Motorola GP339

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