SDSharp and PDW

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SCPD

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While using these to programs decoding will be doing great and then it will just stop. I cant find a reason why. They are no changes to the settings. Any ideas?
 

moonbounce

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I would check the RF gain, your AGC and squelch. My understanding is that PDW needs a strong signal.
 

morfis

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PDW certainly doesn't need a particularly strong signal. There are seven nooelec nesdr dongles plugged into a hub on this PC, each controlled by SDR# (which I'm guessing is the same as your "SDSharp" and feeding seven instances of PDW via VAC. None of them have ever stopped 'randomly'.

Running seven instances of SDR# is really a waste of resources but it was quick attempt to see how many would work at once and I've never got round to shutting it down again. The answer was more than 7 and I ought to try a few more as I have two more hubs to play with now.
 

moonbounce

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Just doing an experiment on my SDR/PDF settings and i find that the higher i go in the squelch setting the less signal to no signal i get. I have to have the squech setting at around 40 as opposed to 65 for everything else.

MB
 

morfis

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Squelch here is OFF for all data decoding applications.
'Filter Audio' is NOT checked for data decoding audio output.
 

moonbounce

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Check PPM and RF gain, too high of an RF gain could cause problems. I also find VHF signals harder to capture than UHF signals.
 

morfis

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Check ...... RF gain, too high of an RF gain could cause problems.
+1 to this.

A decent aerial away from electrical interference and then careful adjustment of the gain will keep the noise down and therefore give you a better data signal.
 

fourthhorseman

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PDW has routinely been problematic for me, using VAC's to pipe the audio never gave me a strong enough data stream.
the meter rarely rose above half and was constantly getting the yellow alert triangle.

Solved all this by completely altering my set up..

No more RTLSDR connected to the PC.
Raspberry Pi3 does all the CPU work..over home network, via ethernet.
.SDR# is running in TCP client.on a 2G ram/1.6ghz cpu DELL Inspiron 1501
Running Flawless.
Now using a simple stereo patch cable to pipe the audio to my Dell XFR and now DSD+(with LRRP working Great) , KGAcars and PDW perform ridiculously well..even while running RTL1090 & ADSBScope and Trunk88..

Now i have too much going on...Too much data being displayed...(ha...first world problems, Eh!?)

Absolutely possible my VAC's are not set up propper, but after years of struggle, its choochin along great..
And at this point..It aint broke anymore..so..........
 
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moonbounce

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For my setup I use VB Cable with any RTL dongle with SDR Sharp and PDW 3.1 and it works perfect. I don't know if it has anything to do with the difference between VAC and VB Cable but it works great.
 

morfis

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For my setup I use VB Cable with any RTL dongle with SDR Sharp and PDW 3.1 and it works perfect. I don't know if it has anything to do with the difference between VAC and VB Cable but it works great.
I've no idea what the differences are but I do know that on one PC I use VAC and on the other VB Cable. Always used VAC in the past but it won't play ball on this particular PC.
To confuse matters further, both PCs use the same processor, have the same version of windows, same make and quantity of RAM, same motherboard, Same SSD/hardrive combo......

So the one on which VAC works has a lot of 'cables' and this one has three. No problems with either in terms of their working but VAC certainly a bit more effort to set up than VB Cable initially.

Back to PDW and it's meter.

On one flex freq I rarely see the meter show more than 5% yet it's giving me 100% good decodes and doesn't appear to be missing any pages - I guess the poor percentage figure is because it's also trying to decode 'noise' and failing.
On a quieter flex freq I constantly get 100% but the actual decodes will vary from being perfect to being almost totally garbled (whilst still showing 100% on the meter).
...so I pay no attention to the meter or the triangle/percentage decode
 

mjbtnus

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May 28, 2017
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Franklin, TN
PDW has routinely been problematic for me, using VAC's to pipe the audio never gave me a strong enough data stream.
the meter rarely rose above half and was constantly getting the yellow alert triangle.

Solved all this by completely altering my set up..

No more RTLSDR connected to the PC.
Raspberry Pi3 does all the CPU work..over home network, via ethernet.
.SDR# is running in TCP client.on a 2G ram/1.6ghz cpu DELL Inspiron 1501
Running Flawless.
Now using a simple stereo patch cable to pipe the audio to my Dell XFR and now DSD+(with LRRP working Great) , KGAcars and PDW perform ridiculously well..even while running RTL1090 & ADSBScope and Trunk88..

Now i have too much going on...Too much data being displayed...(ha...first world problems, Eh!?)

Absolutely possible my VAC's are not set up propper, but after years of struggle, its choochin along great..
And at this point..It aint broke anymore..so..........
I've recently come into the possession of two Pi2B's that I would love to explore a setup like what you describe. What RTL-SDR "server" are you running on your Pi3 that will feed a datastream to SDR#? Best I can tell, the largest difference between Pi2B and Pi3 is faster CPU in the Pi3. While a definite plus, do you think a Pi2B will suffice? I would like to setup two of them to potentially feed a trunking setup, or just dual "VFO" if nothing else. I assume you have gigabit backbone. Any issues with packet loss or latency that negatively impacts SDR# decoding of the TCP stream?

Thanks!
 

mandcaff

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northern michigan
A little off topic, just wondering is there a way to find local pages? I set this up in bout 20 mins and seems to be working well, but seems all I receive are distant pages
 
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