Date   

Re: Distorted Audio in WFM

Ron
 

BFM?

On 03/02/2020 21:22, pjhuffman39 wrote:

I am using V3.0.19 with the RSPdx and the audio is very distorted in the WFM mode.  I have tried adjusting volume, RF/IF gain and bandwidth, but nothing seems to correct the problem.  Any ideas?  The maximum bandwidth in this mode is 40K, which doesn’t seem to be wide enough.

 

Paul-K8RIP

 

Attachments:



Re: 3.0.20 Released

barry williams
 

I’m replying to this because I’m going to install Windows 7, 64 bit on an unused computer soon. I’m neither an old dog, nor selfish as I need this for older software that doesn’t like Windows 8.1. I really need to run this radio related software. I’ve only recently rediscovered SDR Console and I could really use v3.0.xx on both computers.

This a good moment to thank Simon for this excellent program. I haven’t had the opportunity to use my old Airspy, but the Elad S2 and a Perseus both work well with v3.0.19. (There’s a small bug that I need to report in a separate message when I’m back home, but a workaround is easy to use at the moment.)


Barry Williams

On Feb 3, 2020, at 7:14 AM, Mark Cayton <oldjackbob@...> wrote:

It's rather presumptuous (and selfish) to expect Simon to remain chained to obsolete technology (and Windows 7 is unarguably obsolete) just because a user of his FREE software doesn't feel any need to modernize.

In today's world, if you can't run with the big dogs (and Simon is a Big Dog), stay on the porch.
-- 
Mark  K1LSB


Re: Distorted Audio in WFM

jdow
 

Have you considered using a wider bandwidth on the "filter" setting in the DSP panel? 40 kHz is never going to cut it for broadcast FM. Set to 250 kHz and see what happens.

{o.o}

On 20200203 13:22:01, pjhuffman39 wrote:
I am using V3.0.19 with the RSPdx and the audio is very distorted in the WFM mode.  I have tried adjusting volume, RF/IF gain and bandwidth, but nothing seems to correct the problem.  Any ideas?  The maximum bandwidth in this mode is 40K, which doesn’t seem to be wide enough.
Paul-K8RIP
Screenshot-2020-02-03-143727.png


Distorted Audio in WFM

pjhuffman39
 

I am using V3.0.19 with the RSPdx and the audio is very distorted in the WFM mode.  I have tried adjusting volume, RF/IF gain and bandwidth, but nothing seems to correct the problem.  Any ideas?  The maximum bandwidth in this mode is 40K, which doesn’t seem to be wide enough.

 

Paul-K8RIP

 


Re: Strange VLF signals

Alan
 

Actually, kidding aside, it's just JXN in Norway.
16.40 kHz
<https://www.mwlist.org/vlf.php#top>
Kriss,

Yes, Allan has already said that.
But he was asking about the "signals" just below that.
I put " " because I suspect they are spurii, but can't be sure..

73 Alan G4ZFQ


Re: 3.0.20 Released

jdow
 

WDDM 1.3 surely is a PITA. I had to disable it on some embedded systems we sell before they would work correctly.
{O.O}

On 20200203 12:32:14, Simon Brown wrote:
No,
In this case a hardware configuration I can't get around ☹ . Read https://www.sdr-radio.com/RecAndPlayback#Problems - it's well documented by Microsoft.
Simon Brown, G4ELI
https://www.sdr-radio.com
-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow
Sent: 03 February 2020 20:26
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] 3.0.20 Released
Recording uses a feature that is not present before Windows 8.1.
{^_^}
On 20200203 03:57:06, Mark Pettifor wrote:
Unlike Terry, I kind of expected new releases to still work on Windows 7 for at least a while yet.

I think I read somewhere that 70% of desktops are still using it.

Why did you cut off support for Windows 7 so soon after MS cut off support for it? (And technically they didn't stop supporting it, if you want to pay money for extended support.)

Mark Pettifor
KC9DOC
EN71 Goshen, IN



Re: Strange VLF signals

Kriss Kliegle KA1GJU
 

Close the doors, pull the shades down low, and wait for the black helicopters!

Actually, kidding aside, it's just JXN in Norway. 
16.40 kHz top
Country   Station (web site link) Transmitter (GoogleMaps link)
* = high precision
  kW   Remarks
NOR   JXN 0000-0200, 0400-0600, 0800-1000, 1200-1400, 1600-1800, 2000-2200 Gildeskål/Novik *   45   FSK, 200 Bd

17.20 kHz  Go to the following for list of LF freqs and stations:
https://www.mwlist.org/vlf.php

73 Kriss KA1GJU


Re: 3.0.20 Released - Update

Simon Brown
 

No,

It's just the point in the my modulation DLL where I extract the audio. Unprocessed sounds lovely but by comparison with the received audio it's too quiet. This is something I was going to do in 3.0.20 but forgot.

Simon Brown, G4ELI
https://www.sdr-radio.com

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow
Sent: 03 February 2020 20:38
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] 3.0.20 Released - Update

Re V21 you say, "Transmit audio now sent to the video recorder post-processing (boost, compander, processor, filter, ...) rather than unprocessed." Won't that break on Win 7?

{o.o}


Re: RF Clipper Diode Design

jdow
 

The coax feedline trap is not likely to be good enough to solve his issue. Something I have done in the past, at first because I overshot the right length with enthusiastic cutting, is solder a couple short (20 mm or so) wires to the end of the coax, one to the shield and the other to the center post. Bending the wires towards and away from each other can fine tune the notch frequency. He is going to need more attenuation than this notch can usually provide for real FM DX. And this all gets "messy" quickly enough. BUT, it is a learning experience which is always worthwhile. Knowledge is power.

{^_^}

On 20200203 11:34:29, Tom Crosbie G6PZZ wrote:
A long time ago when I was first licenced, one of the facts of life I learned was that one day, I might interfere with someone's TV reception, very possibly my own. We learned how to make a very simple notch filter using nothing more than a T-piece and a length of coax approx. quarter of a wavelength long. At 88MHz, this would be approx. 0.9m long. If we consider the T configuration, the top bar of the T represents the feedline between antenna and receiver, the upright bar is our 0.9m of coax, or stub. These were often referred to as stub filters. The receiver is tuned to the offending frequency and the stub is then trimmed gradually 5mm at a time until there is a reduction in signal strength. You'll know when you've cut off too much when the signal strength goes back up!
Given Michael's extreme challenge, it might be worth trying as it only costs a few connectors and a length of coax. If this works on one of the frequencies, it will work on the other, make another stub and insert it in the feedline in series with the other. At the other end of the band, the quarter wavelength is just 0.75m so there isn't a huge difference across the whole of Band II. Start a little longer with the stubs than theory dictates, perhaps 1m. As to the theory behind this, the stub will be resonant at a frequency relative to its length. This will have the effect of filtering out some of the signal. There are more learned people around here that could explain this more eloquently and mathematically than I can!
Martin's solution is a great option and is what the professionals would use. But it's quite expensive, even buying surplus. I recall similar home brew projects literally featuring beer barrels. I offer this from a dim and distant memory in the hope that a simple, low-cost option just might help.
Tom G6PZZ
-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Michael.2E0IHW via Groups.Io
Sent: 03 February 2020 14:11
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] RF Clipper Diode Design
That was my concern, Martin.
Even though challenging for VHF diy, further details of the theory and practice would be appreciated.
Michael 2E0IHW
On 03/02/2020 13:38, Martin via Groups.Io wrote:

My understanding of the problem is that he is trying to receive weak
FM Band II broadcasts signals in the presence of strong local transmissions.
...
The filters that we used were often a 1/4 wave loaded line or helical,
enclosed within a metal tube about the size of a domestic fire
extinguisher, and each one was tuned to a specific transmission
frequency, so unfortunately it's not really a practical solution for
home use.
Martin - G8JNJ


Re: 3.0.20 Released - Update

jdow
 

Re V21 you say, "Transmit audio now sent to the video recorder post-processing (boost, compander, processor, filter, ...) rather than unprocessed." Won't that break on Win 7?

{o.o}

On 20200203 05:41:09, Simon Brown wrote:
Hi,
https://www.sdr-radio.com/release-notes
This kit should fix the W7 / All 32-bit crashes.
Simon Brown, G4ELI
https://www.sdr-radio.com
*From:*main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> *On Behalf Of *Simon Brown via Groups.Io
*Sent:* 03 February 2020 07:26
*To:* SDR-Radio.com <main@SDR-Radio.groups.io>
*Subject:* [SDR-Radio] 3.0.20 Released
SDR Console 3.0.20 available, includes its own MP4 video recorder.
https://www.sdr-radio.com/release-notes#Release3-0-20 <https://www.sdr-radio.com/release-notes%23Release3-0-20>
Simon Brown, G4ELI
https://www.sdr-radio.com


Re: 3.0.20 Released

Simon Brown
 

No,

In this case a hardware configuration I can't get around ☹ . Read https://www.sdr-radio.com/RecAndPlayback#Problems - it's well documented by Microsoft.

Simon Brown, G4ELI
https://www.sdr-radio.com

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow
Sent: 03 February 2020 20:26
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] 3.0.20 Released

Recording uses a feature that is not present before Windows 8.1.
{^_^}

On 20200203 03:57:06, Mark Pettifor wrote:
Unlike Terry, I kind of expected new releases to still work on Windows 7 for at least a while yet.

I think I read somewhere that 70% of desktops are still using it.

Why did you cut off support for Windows 7 so soon after MS cut off support for it? (And technically they didn't stop supporting it, if you want to pay money for extended support.)

Mark Pettifor
KC9DOC
EN71 Goshen, IN



Re: 3.0.20 Released

jdow
 

And you can switch for free. Get the mediacreation tool from MS and go to town.
{^_^}

On 20200203 05:36:28, Kriss Kliegle wrote:
Ditto! (Marks comments)
     I just picked up an HP laptop with an i3 for very small quid (money) on Craigslist. Took a LONG time for W10 to wipe and reset (about 4 hours), but I now have another machine to be dedicated for server service. The i5's and i7's I got from Craigslist are just too sweet to be sitting in the basement or repeater shed for server service.😉 I was hesitant about the switch to W10, but now it's my preferred OS.
   BTW, the i3 runs SDRC, even via WiFi just fine, with no stuttering!
   If somebody wants to dwell in the past, I have a stack of Acer netbooks with Windows XP available! 😆
73 Kriss KA1GJU


Re: 3.0.20 Released

jdow
 

Recording uses a feature that is not present before Windows 8.1.
{^_^}

On 20200203 03:57:06, Mark Pettifor wrote:
Unlike Terry, I kind of expected new releases to still work on Windows 7 for at least a while yet.
I think I read somewhere that 70% of desktops are still using it.
Why did you cut off support for Windows 7 so soon after MS cut off support for it? (And technically they didn't stop supporting it, if you want to pay money for extended support.)
Mark Pettifor
KC9DOC
EN71 Goshen, IN


Re: RF Clipper Diode Design

jdow
 

You probably want multiple different antenna connections and SDRC configurations. The configuration in the first image is probably your best setup conditions unless you filter out commercial FM while receiving other things. I doubt there is much you can do to tame the super power FM stations. Walls don't do much to attenuate FM broadcast. A hill is what it usually takes to make a big difference. A lot of buildings might bring in 20 dB of attenuation which would protect the front end from those signals. An off frequency antenna could buy another 10 dB or more. (Be careful if you install a good FM antenna. +81 dBm with 80 dB of attenuation from basic path loss is still more than 0 dBm. If your radio has not died already it likely can stand well more than 0 dBm on its input. 1V peak is where I'd expect things to get dicey. That is about +14 dBm.)

K9YC, Jim Brown, has some nice articles to read about surviving in a theatrical environment with worse signal levels than you are suffering. http://k9yc.com/publish.htm The theater he worked in until he retired was in Chicago in a tall building with a large number of very powerful broadcast stations. He made the theater's audio systems work in that environment.

To sum it up, I believe you will find FM DX with SDRs a rather unrewarding experience at your present location. But, you can make ham radio work nicely with an FM band filter - or two or three. The BSF-108+ from Mini-Circuits can provide 60 dB of attenuation. So one of them should allow you to run with full sensitivity on most ham bands. And it appears for FM reception you can personally redefine "DX" and run without the filter with reduced front end gain. That spectrum splash is what happens when A/D converters become overloaded. It is a basic limitation on the high power end.

{^_^}

On 20200203 02:50:22, goscickiw wrote:
I think it's sort of solved with the 100.9MHz signal. I had automatic IF gain set, the signal became better after I changed it to manual.
In case of other weak signals, I tried with a 4-20dB variable attenuator and they became much worse or disappeared, while the strongest signals stayed just as good. Same situation when I use a short piece of wire or a smaller antenna.
These signals come from different transmitters so a directional antenna would help, but the problem here is space. I can't put a 5 element FM Yagi on a wall.
Also something I should have mentioned, my antenna doesn't have a direct line of sight to the transmitters because of location - surrounded by higher buildings. Putting it on the roof would probably help, but would require much convincing of other residents. It's a vertical folded dipole.
Here is how the signals look like on the spectrum in normal conditions - no attenuator.
When I increase the RF gain by 1, the spectrum becomes this mess:
With an attenuator:
I'm not sure why this subject expanded in this direction... Originally I wanted to protect my HackRF One, that I use just for testing stuff like modulators and usually don't connect an antenna to it, from accidentally giving it signal stronger than its nominal -5dBm... Then I started talking about receiving FM. WTF brain.


Re: 3.0.20 Released

Simon Brown
 

Hi,

 

I’ve just updated the text to make it clearer that there’s really no workaround. It’s annoying for you and also for me, I would like it to run on all PCs. I have a very nice i7 4th generation Acer laptop which doesn’t support the video recorder .

 

https://www.sdr-radio.com/RecAndPlayback#Problems

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Steve Jerome
Sent: 03 February 2020 20:06
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] 3.0.20 Released

 

Thanks, but I've no idea what that means...other than you saying "There's really no workaround"...

Steve


Re: 3.0.20 Released

Steve Jerome
 

Thanks, but I've no idea what that means...other than you saying "There's really no workaround"...

Steve


Re: 3.0.20 Released

Simon Brown
 

Steve,

 

“The video recorder uses the Windows Desktop Duplication API which does not support being run against the discrete GPU on a Microsoft Hybrid system.”

 

There’s really no workaround.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Steve Jerome
Sent: 03 February 2020 19:36
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] 3.0.20 Released

 

Sorry, Simon I have the same "error code -10" issue and I cannot understand how to resolve it, if it's even possible, from the link you provided.  Or maybe I'm just not IT literate enough...

Regards,

Steve 


Re: Strange VLF signals

Alan
 


I think I can identify a Norwegian transmission at 16.4KHz, but just LF of it there is a broadband transmission, or maybe local interference, that seems to have three modes.
A spread of carriers about 100Hz apart... attached
A narrower spread, much weaker
And off for varying periods.... attached
Allan,

I've never seen this. Is it on now?
(500'? my antenna is not 5')

73 Alan G4ZFQ


Re: 3.0.20 Released

Steve Jerome
 
Edited

Sorry, Simon I have the same "error code -10" issue and I cannot understand how to resolve it, if it's even possible, from the link you provided.  Or maybe I'm just not IT literate enough...WIN10-64 bit desktop.

Regards,

Steve


Re: RF Clipper Diode Design

Tom Crosbie G6PZZ
 

A long time ago when I was first licenced, one of the facts of life I learned was that one day, I might interfere with someone's TV reception, very possibly my own. We learned how to make a very simple notch filter using nothing more than a T-piece and a length of coax approx. quarter of a wavelength long. At 88MHz, this would be approx. 0.9m long. If we consider the T configuration, the top bar of the T represents the feedline between antenna and receiver, the upright bar is our 0.9m of coax, or stub. These were often referred to as stub filters. The receiver is tuned to the offending frequency and the stub is then trimmed gradually 5mm at a time until there is a reduction in signal strength. You'll know when you've cut off too much when the signal strength goes back up!

Given Michael's extreme challenge, it might be worth trying as it only costs a few connectors and a length of coax. If this works on one of the frequencies, it will work on the other, make another stub and insert it in the feedline in series with the other. At the other end of the band, the quarter wavelength is just 0.75m so there isn't a huge difference across the whole of Band II. Start a little longer with the stubs than theory dictates, perhaps 1m. As to the theory behind this, the stub will be resonant at a frequency relative to its length. This will have the effect of filtering out some of the signal. There are more learned people around here that could explain this more eloquently and mathematically than I can!

Martin's solution is a great option and is what the professionals would use. But it's quite expensive, even buying surplus. I recall similar home brew projects literally featuring beer barrels. I offer this from a dim and distant memory in the hope that a simple, low-cost option just might help.

Tom G6PZZ

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Michael.2E0IHW via Groups.Io
Sent: 03 February 2020 14:11
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] RF Clipper Diode Design

That was my concern, Martin.

Even though challenging for VHF diy, further details of the theory and practice would be appreciated.

Michael 2E0IHW


On 03/02/2020 13:38, Martin via Groups.Io wrote:

My understanding of the problem is that he is trying to receive weak
FM Band II broadcasts signals in the presence of strong local transmissions.
...
The filters that we used were often a 1/4 wave loaded line or helical,
enclosed within a metal tube about the size of a domestic fire
extinguisher, and each one was tuned to a specific transmission
frequency, so unfortunately it's not really a practical solution for
home use.
Martin - G8JNJ

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