Looking for SDR idea suggestions.


KD7JYK DM09 <kd7jyk@...>
 

I've looked online on and off for a year or two, and haven't found an answer, or example to an idea I have.

Something along the lines of a scanner, or scanning, but an entire band, for example, 10m, or 20m, and if a signal is above a threshold, the receiver will stop on the frequency. Frequency would be unknown, so the entire band in reasonable steps for the mode.

Think of it as an old analog scanner search function, set low frequency limit, then high frequency limit, press search, something pops up, scanning stops until transmission ends, then continues. The idea is, if there are close, or strong signals on a band, such as a local net, or going into an area with some activity, but not sure where it is, the SDR could track it, so to speak, mode, AM, FM, SSB, et cetera, could be set after the first few hits.

From what I understand, an SDR is fast, so it seems if a signal pops up anywhere, and was above a threshold, searching/locking, then continuing would be nearly instantaneous until the next transmission

Anyone doing this already? I've found mention of people using some SDRs as a scanner, and putting in a few frequencies, like channels to search through, but I haven't found any references to sweeping all of 10m.

Ideas? Looking for examples of SDRs that can do this, software, some basic settings.

Thanks.

Kurt


Greg Ella
 

SDR receivers convert an entire block of spectrum into live streaming I/Q data
that can be processed in real time.  That's why we get the nice real time
spectrum display, and why we can record an entire band to hard drive and
"tune around" inside of it after the fact.

Most modern SDR receivers can cover over 4 MHz of simultaneous bandwidth, which would cover the
entire span of any of our Amateur bands until we get up to 70 CM.  Even there, I think that the band plan for
specific uses, live FM Simplex or Repeater Output, is less than 4 MHz wide.  If not, there are some
receivers, like BladeRF, that can cover 30 MHz or more of bandwidth.

Given the above, it seems to me that your approach, scanning across frequencies one at a time with a defined step size,
would be a step backwards.  Think of older spectrum analyzers that used swept tuning, vs modern RTSA analyzers.

I think that what would be useful here is an application that lets you set a frequency range (within the maximum bandwidth
of the receiver), the trigger level, and the demodulation mode.  The software would detect any signal that pops up above the detection level,
snap to it, and pipe out demodulated audio.  As a bonus, it could trigger recording to an audio file, and the recording would be time, date and frequency
stamped.

Does anybody know if such an application exists yet?

Greg Ella
N0EMP


On Sun, Nov 28, 2021 at 7:07 AM KD7JYK DM09 <kd7jyk@...> wrote:
I've looked online on and off for a year or two, and haven't found an
answer, or example to an idea I have.

Something along the lines of a scanner, or scanning, but an entire band,
for example, 10m, or 20m, and if a signal is above a threshold, the
receiver will stop on the frequency.  Frequency would be unknown, so the
entire band in reasonable steps for the mode.

Think of it as an old analog scanner search function, set low frequency
limit, then high frequency limit, press search, something pops up,
scanning stops until transmission ends, then continues.  The idea is, if
there are close, or strong signals on a band, such as a local net, or
going into an area with some activity, but not sure where it is, the SDR
could track it, so to speak, mode, AM, FM, SSB, et cetera, could be set
after the first few hits.

 From what I understand, an SDR is fast, so it seems if a signal pops up
anywhere, and was above a threshold, searching/locking, then continuing
would be nearly instantaneous until the next transmission

Anyone doing this already?  I've found mention of people using some SDRs
as a scanner, and putting in a few frequencies, like channels to search
through, but I haven't found any references to sweeping all of 10m.

Ideas?  Looking for examples of SDRs that can do this, software, some
basic settings.

Thanks.

Kurt






David Patton
 

Kurt,

This is a way to do most of what you want:  https://youtu.be/9AR-QemkSic


Joe M.
 

What you are describing sounds like the Fast Scanner plugin for SDR#.

Joe M.

On 11/27/2021 10:38 PM, KD7JYK DM09 wrote:
I've looked online on and off for a year or two, and haven't found an
answer, or example to an idea I have.

Something along the lines of a scanner, or scanning, but an entire band,
for example, 10m, or 20m, and if a signal is above a threshold, the
receiver will stop on the frequency. Frequency would be unknown, so the
entire band in reasonable steps for the mode.

Think of it as an old analog scanner search function, set low frequency
limit, then high frequency limit, press search, something pops up,
scanning stops until transmission ends, then continues. The idea is, if
there are close, or strong signals on a band, such as a local net, or
going into an area with some activity, but not sure where it is, the SDR
could track it, so to speak, mode, AM, FM, SSB, et cetera, could be set
after the first few hits.

From what I understand, an SDR is fast, so it seems if a signal pops up
anywhere, and was above a threshold, searching/locking, then continuing
would be nearly instantaneous until the next transmission

Anyone doing this already? I've found mention of people using some SDRs
as a scanner, and putting in a few frequencies, like channels to search
through, but I haven't found any references to sweeping all of 10m.

Ideas? Looking for examples of SDRs that can do this, software, some
basic settings.

Thanks.

Kurt





Dionisis “Dennis” Drakopoulos
 

Greetings Kurt!
I have been using SDR SHARP (with community plugins) version 1732 and in specific plugin named FREQUENCY SCANNER.
With an RTL SDR (~2MHz sampling frequency) I can sweep whole 144MHz VHF band in realtime. The plugin is then able to detect any frequency slot (12500Hz step) crosses over a threshold in SNR and logs the number of seconds slot satisfied this condition. Doing so I get informed which are the VHF frequencies mostly used. My objective was to find which VHF frequencies are used more for ragchewing - discussions.
Such can be complemented with SNR LOGGER plugin, that stores in a .csv file the SNR value of a specific frequency over a specific time step e.g. 1sec. Afterwards .csv file can be further processed with an Excel to extract more useful information and visualization of the data.
Should also mention FMS FREQUENCY MANAGER + SCANNER plugin that shows information of a VFO selected frequency, e.g.one with maximum SNR as detected by FREQUENCY SCANNER, that I also found useful. Of course one should provision the information intended to be displayed in return. Unless a contribution to such for different IARU regions is made available, and I don't know about it.

73 de SV1CDN, Dennis.


sdrs.freqmgr@...
 

Hi Kurt.  I'm Jeff N8GJL and the author of the Frequency Manager Suite. 

The Frequency Manager Suite supports SDR# 1812 and higher.  FMSuite contains the following plugins:

  • Frequency Manager database of stations
  • Radio Scanner to find those stations.  Scan with or without Step Size to control what's scanned, and you set the lower and upper freq range
  • Activity Logger keeps a record of frequencies on which the scanner stops
  • Frequency Entry allows you to type the listening frequency and the center frequency explicitly
  • Frequency Data Display show some details of the station you are listening to, if that is in the database
  • Scanner Decisions displays details about scanner activity and why the scanner stopped – or did not stop – on a specific frequency
  • Scanner Metrics records a scanning session and charts the Busiest Frequencies by Count, Busiest Frequencies by transmission duration, and Busiest Times for a Frequency
  • Scheduler to schedule frequency changes
  • The Data Tools standalone app allows you to export your database or import data from several other databases found on the internet.

I hope this helps.  Let me know if you have any questions
Jeff


George Stein - NJ3H
 

Hi Jeff, 
Just curious if your plug in will scan a list of specific frequencies, like the old time scanners did? 

Thanks, 
George


On Mon, Nov 29, 2021 at 1:14 PM, sdrs.freqmgr@...
<sdrs.freqmgr@...> wrote:
Hi Kurt.  I'm Jeff N8GJL and the author of the Frequency Manager Suite. 

The Frequency Manager Suite supports SDR# 1812 and higher.  FMSuite contains the following plugins:

  • Frequency Manager database of stations
  • Radio Scanner to find those stations.  Scan with or without Step Size to control what's scanned, and you set the lower and upper freq range
  • Activity Logger keeps a record of frequencies on which the scanner stops
  • Frequency Entry allows you to type the listening frequency and the center frequency explicitly
  • Frequency Data Display show some details of the station you are listening to, if that is in the database
  • Scanner Decisions displays details about scanner activity and why the scanner stopped – or did not stop – on a specific frequency
  • Scanner Metrics records a scanning session and charts the Busiest Frequencies by Count, Busiest Frequencies by transmission duration, and Busiest Times for a Frequency
  • Scheduler to schedule frequency changes
  • The Data Tools standalone app allows you to export your database or import data from several other databases found on the internet.

I hope this helps.  Let me know if you have any questions
Jeff


sdrs.freqmgr@...
 

Hi George.  Yes, you can create Groups of frequencies and then scan a Group instead of a frequency range.

Thanks,
Jeff


KD7JYK DM09 <kd7jyk@...>
 

On 11/28/2021 07:56, David Patton wrote:
This is a way to do most of what you want: https://youtu.be/9AR-QemkSic

THAT is amazing!

Right now my military airband scans are with a Yaesu FT-7900, and I think the sweep may be in the ten to fifteen minute range, and as expected, I've heard one signal.

That birdie removal tool is incredible too.

In your video, near the right side of the waterfall, what are the alternating bursts of signal? They look like little alternating ticks. It also shows some carriers below those, but I don't see them on the waterfall, just the spikes.

I see the frequency entry box had multiple rows. Can multiple frequency ranges be entered, for example, 118-136, and 225-380, and both airband ranges be scanned? If so, that would be very handy!

Any information greatly appreciated!

Thanks!

Kurt


David Patton
 

Glad you found it useful. The video belongs to https://frugalradio.com/

You can configure multiple frequency ranges for scanning. However, I think you can only scan one of them at a time.

David


On Wed, Dec 1, 2021 at 1:01 AM KD7JYK DM09 <kd7jyk@...> wrote:
On 11/28/2021 07:56, David Patton wrote:
This is a way to do most of what you want: https://youtu.be/9AR-QemkSic

THAT is amazing!

Right now my military airband scans are with a Yaesu FT-7900, and I
think the sweep may be in the ten to fifteen minute range, and as
expected, I've heard one signal.

That birdie removal tool is incredible too.

In your video, near the right side of the waterfall, what are the
alternating bursts of signal?  They look like little alternating ticks.
  It also shows some carriers below those, but I don't see them on the
waterfall, just the spikes.

I see the frequency entry box had multiple rows.  Can multiple frequency
ranges be entered, for example, 118-136, and 225-380, and both airband
ranges be scanned?  If so, that would be very handy!

Any information greatly appreciated!

Thanks!

Kurt