SDR# Can't get a strong enough signal on SDR to decode on PDW

[JensenAPN]

Hi, I've recently purchased an antenna set with usb plug-in & installed SDR, VBAudio and PDW in hopes of picking up my local Fire & Rescue service pagers for ongoing jobs.

I have had troubles from the get go, I have the antenna in the upstairs front bedroom windowsill, however my signal on the frequency 153.350.000 comes and goes - and then i can rarely achieve above 70% on PDW...any ideas to help please?

 

[slicerwizard]

Use a proper VHF antenna with a good counterpoise.

 

[morfis]

Another recent thread about a low signal and PDW which the search would throw out...may be worth a read?

Low to no signal in PDW

Hey peeps! I've recently bought a RTLSDR dongle, RTL2832U. I've followed the set-up of both this, VBAudiocable and PDW. I've put my settings to the following, (see file attached). Also included is PDW signal and what's coming out. I can't seem to get over 20% which is very sad since I...

forums.radioreference.com

 

[JensenAPN]

Another recent thread about a low signal and PDW which the search would throw out...may be worth a read?

Low to no signal in PDW

Hey peeps! I've recently bought a RTLSDR dongle, RTL2832U. I've followed the set-up of both this, VBAudiocable and PDW. I've put my settings to the following, (see file attached). Also included is PDW signal and what's coming out. I can't seem to get over 20% which is very sad since I...

forums.radioreference.com

Thanks, I’ll take a look.

 

[JensenAPN]

Use a proper VHF antenna with a good counterpoise.

Okay, any recommendations? This is the product I purchased:

NooElec NESDR SMArt v4 Bundle - Premium RTL-SDR w/Aluminum Enclosure, 0.5PPM TCXO, SMA Input & 3 Antennas. RTL2832U & R820T2-Based Software Defined Radio NooElec NESDR SMArt v4 Bundle - Premium RTL-SDR w: Amazon.co.uk: Electronics

 

[spongella]

What is the antenna set you are speaking of? What is the frequency of the pager?

An outdoor antenna as high up as possible will get better reception. Also, set the RF gain higher on the dongle. Hope this helps.

 

[morfis]

So, UK PageOne National POCSAG frequency?
You should be able to receive that using a damp cabbage leaf unless you are in the middle of nowhere.
The screenshots of mine in that other thread were from a rtl device with it's small antenna on a windowsill.

Which Trumptons do you want to monitor? Do they use the Natiopnal Flex or POCSAG system or do they use the nationally allocated local frequency?

(edit......terrible spelling)

 

[JensenAPN]

What is the antenna set you are speaking of? What is the frequency of the pager?

An outdoor antenna as high up as possible will get better reception. Also, set the RF gain higher on the dongle. Hope this helps.

I am using a telescopic antenna mask with variable frequency. The frequency of the pager is 153.350.000.

I have the RF gain on 20.7 and thats picking up 18% on PDW however I'm getting through tone only every few minutes so it's obviously picking up something. I will attach a photo of the setup shortly.

 

[JensenAPN]

So, UK PageOne National POCSAG frequency?
You should be able to receive that using a damp cabbage leaf unless you are in the middle of nowhere.
The screenshots of mine in that other thread were from a rtl device with it's small antenna on a windowsill.

Which Trumptons do you want to monitor? Do they use the Natiopnal Flex or POCSAG system or do they use the nationally allocated local frequency?

(edit......terrible spelling)

Yes that's correct. I'm looking to pickup Warwickshire/Leicestershire/Northamptonshire. As far as I'm aware all three use POCSAG. I only picked it up recently as a friend of mine in over 100 miles away pick them up just fine, so I thought if I use the same set up as them on the same frequency as them (153.350.000) will pick these FRS just fine as I'm located much closer. Instead on the rare occasion that I have had over 80% on PDW, I've picked up Ambulance calls in Manchester.....which is not what i'm after.

 

[morfis]

Yes that's correct. I'm looking to pickup Warwickshire/Leicestershire/Northamptonshire. As far as I'm aware all three use POCSAG. I only picked it up recently as a friend of mine in over 100 miles away pick them up just fine, so I thought if I use the same set up as them on the same frequency as them (153.350.000) will pick these FRS just fine as I'm located much closer. Instead on the rare occasion that I have had over 80% on PDW, I've picked up Ambulance calls in Manchester.....which is not what i'm after.

153.350 is transmitted Nationally....all the messages go out on all the transmitters.

Getting ahead of things but you would need to create a filter file to display the pagers you want but not the others.

Back to your setup. Did you read through the other thread? Forget the % number - use that meter to see if your audio is being routed to PDW and then ignore it.

Sensible Gain setting?
Correct bandwidth?
Correct Mode?
Audio level not too high?

 

[JensenAPN]

I attached some screenshots. I'm sorry but I am pure beginner and learning as I go.... I have read through the other thread and tried a variety of options suggested in there (all the way down to setting the telescopic antenna to 45cm).

Gain is on 28 dB
PPM is on 27 (was messing around with it and it took me up to 15%) so left it at that for now.
Bandwidth is 11,270
I am on NFM
Using the Blackman-Harris 4 filter

Not sure how I adjust the audio levels.

 

[merlin]

One thing I found with these dongles is they lack any filtering. With a VHF(140-170Mhz) bandpass filter in front of the dongle, it stablizes the AGC/RF gains. That makes adjustments a lot easier and stable.
I am guessing your noise floor is up and down, this filter fixes that.

 

[JensenAPN]

Little bit of an update for you all:

- Still not decoding however I have narrowed down my reasons for not getting a proper signal to location of antenna.
- I have purchased a new dongle directly from RTL-SDR along with a fresh antenna.

Will wait for these to arrive, I'll set them up and try various locations around me to see if they work at all.

 

[morfis]

I attached some screenshots. I'm sorry but I am pure beginner and learning as I go.... I have read through the other thread and tried a variety of options suggested in there (all the way down to setting the telescopic antenna to 45cm).

Gain is on 28 dB
PPM is on 27 (was messing around with it and it took me up to 15%) so left it at that for now.
Bandwidth is 11,270
I am on NFM
Using the Blackman-Harris 4 filter

Not sure how I adjust the audio levels.

The signal looks low but I've seen worse decode ok.
PPM is wrong - your device will typically work fine for general listening and pager docoding if this is left at 0
Bandwidth looks OK (though the signal is not centred as it should be) but I'd change it to 12500 initially
Mode/filter fine

sdrsharp: Have you got the audio filter checked? It shouldn't be.
pdw: Only enable the POCSAG decoder (Flex and POCSAG are not mixed)
pdw: Which soundcard interface have you set (I use 'discriminitor 1')
If possible try the setup outside in some clear space - plastic bag round the rtl device and a USB extension lead would allow you to keep the computer inside if you have the snow we have


You've posted as I was typing.....
Why do you think you need another rtl device?
(though you'll find plenty of uses for two, three four......)

 

[JensenAPN]

The signal looks low but I've seen worse decode ok.
PPM is wrong - your device will typically work fine for general listening and pager docoding if this is left at 0
Bandwidth looks OK (though the signal is not centred as it should be) but I'd change it to 12500 initially
Mode/filter fine

sdrsharp: Have you got the audio filter checked? It shouldn't be.
pdw: Only enable the POCSAG decoder (Flex and POCSAG are not mixed)
pdw: Which soundcard interface have you set (I use 'discriminitor 1')
If possible try the setup outside in some clear space - plastic bag round the rtl device and a USB extension lead would allow you to keep the computer inside if you have the snow we have


You've posted as I was typing.....
Why do you think you need another rtl device?
(though you'll find plenty of uses for two, three four......)

Okie dokes.

I've set the PPM back to 0.
Bandwidth moved up to 12,500
Unchecked 'Audio Filter'
Disabled Flex decoding

The soundcard interface is already set on 'discriminator 1'. I have attached a photo of it.
I will try moving to an open space shortly....boy do we have some snow where I am!

 

[morfis]

Back to your original post for a moment - you said the signal 'comes and goes', this is what you would expect on pager channels (see the screenshots in the other posts where @Doombar and I show both Flex and POCSAG over several seconds).
If you mean that the whole signal, including the noisefloor comes and goes then you might try lowering the gain a bit (there are tutorials on here and online about how to best set the gain).
If you have the 'squelch' checked in sdrsharp you can uncheck that (I don't rmember if the deafult for that is 'on' like the audio filter)