Frequency Database Station Order


Ken Sejkora
 

Hello all,
Perhaps this has been addressed before, but a quick search of the email topics didn't come up with what I was asking.  Is it possible to sort the order of the entries in the Frequency Database according to strongest station?  For example, when one creates a FMLIST or MWLIST from the fmscan.org website, those files are sorted first by frequency and then by the strongest/most-likely station.  In fact, when you 'import' those records into the SDR Condole Frequency Database, you have the option to select ERP (preferred) or Power.  However, once those files are imported into the SDR Console database, the entries are resorted by frequency and then by alphabetical Station ID.  The order in the fmscan.org is logical in listing the most-likely station first, but once reordered in the SDRC database one loses the 'most-likely' order based on station ERP.  Thanks in advance for any suggestions or ideas.

Ken - WBØOCV
East Falmouth, MA USA


Jim Smith G0OFE
 

It has come up before... I remember asking if the list could be ordered by frequency then distance for VHF FM work - but I think I remember Simon saying it would take a lot of work to implement. Can't remember for sure but it was quite a while ago.

================================
Need help with SDR Console? If you have a problem:
Go to https://www.sdr-radio.com/support
Please follow instructions in that link.
===================================
Jim, Bournemouth, Dorset. IO90BR.
Elad FDM-S2, Airspy HF+, SDRPlay and Funcube Dongle SDR Recievers
8-element OP-DES for Band 2, 8-element LFA for 2m, 3-element LFA for 6m, 20m Windom for HF,. Wellbrook 1530 Loop for LF


On 21/08/2022 19:13, Ken Sejkora wrote:

Hello all,
Perhaps this has been addressed before, but a quick search of the email topics didn't come up with what I was asking.  Is it possible to sort the order of the entries in the Frequency Database according to strongest station?  For example, when one creates a FMLIST or MWLIST from the fmscan.org website, those files are sorted first by frequency and then by the strongest/most-likely station.  In fact, when you 'import' those records into the SDR Condole Frequency Database, you have the option to select ERP (preferred) or Power.  However, once those files are imported into the SDR Console database, the entries are resorted by frequency and then by alphabetical Station ID.  The order in the fmscan.org is logical in listing the most-likely station first, but once reordered in the SDRC database one loses the 'most-likely' order based on station ERP.  Thanks in advance for any suggestions or ideas.

Ken - WBØOCV
East Falmouth, MA USA


Ken Sejkora
 

Thank you, Jim.  I know when you import data from fmscan.org, the SDRC database prefers ERP, but I don’t see how it gets used in the SDRC database.  The ‘Power’ column appears to reflect the station power in kilowatts rather than ERP.

 

I investigated the structure of the MWLIST and FMLIST csv files, and it appears the secondary sorting after frequency is based on the value in the 14th field (Column N).  Stronger stations have a higher value.  Perhaps one could re-sort the SDRC Frequency Database in a similar manner, but again, it doesn’t seem that the corresponding signal strength data are imported into the Frequency Database from the fmscan.org files.

 

Perhaps I’ll try to experiment with a Custom.CSV file to see if I can accomplish what I want.

 

Ken

 

From: Jim Smith G0OFE
Sent: Sunday, August 21, 2022 03:19 PM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Frequency Database Station Order

 

It has come up before... I remember asking if the list could be ordered by frequency then distance for VHF FM work - but I think I remember Simon saying it would take a lot of work to implement. Can't remember for sure but it was quite a while ago.

================================
Need help with SDR Console? If you have a problem:
Go to https://www.sdr-radio.com/support
Please follow instructions in that link.
===================================
Jim, Bournemouth, Dorset. IO90BR.
Elad FDM-S2, Airspy HF+, SDRPlay and Funcube Dongle SDR Recievers
8-element OP-DES for Band 2, 8-element LFA for 2m, 3-element LFA for 6m, 20m Windom for HF,. Wellbrook 1530 Loop for LF

On 21/08/2022 19:13, Ken Sejkora wrote:

Hello all,
Perhaps this has been addressed before, but a quick search of the email topics didn't come up with what I was asking.  Is it possible to sort the order of the entries in the Frequency Database according to strongest station?  For example, when one creates a FMLIST or MWLIST from the fmscan.org website, those files are sorted first by frequency and then by the strongest/most-likely station.  In fact, when you 'import' those records into the SDR Condole Frequency Database, you have the option to select ERP (preferred) or Power.  However, once those files are imported into the SDR Console database, the entries are resorted by frequency and then by alphabetical Station ID.  The order in the fmscan.org is logical in listing the most-likely station first, but once reordered in the SDRC database one loses the 'most-likely' order based on station ERP.  Thanks in advance for any suggestions or ideas.

Ken - WBØOCV
East Falmouth, MA USA

 


Ken Sejkora
 

Hello again, Jim,

 

No luck with getting a Custom.CSV file to accomplish our desired goals.  I was able to create a Custom.csv file, which I could then open with Excel and perform additional sorting options to list stations in order of increasing distance as opposed to Station ID, and then save the resulting file with the re-ordered station list.  However, once you ‘import’ that file into SDRC and ‘add’ the records to the database, that operation of ‘adding’ the information results in a FrequencyDatabase_001.xml that re-orders the list by frequency and Station ID.  I can’t seem to get around that SDRC reordering operation.

 

Upon investigating the FMLIST and MWLIST files created by the fmscan.org website, I made some interesting observations.  As mentioned in my earlier email, both files perform a primary sort by frequency, and a secondary sort by some predicted signal strength, strongest stations first.  I’d be interested in knowing how the predicted signal strength is calculated.  I suspect that distance/proximity comes into pay, as well as station power or ERP.  However, the sorting by signal strength even occurs with stations that don’t even list a power or ERP value.  Perhaps the fmscan.org file generator assumes some minimal power level for those stations that don’t include a power value.  Regardless, the signal strength values calculated in the fmscan.org FMLIST and/or MWLIST files are *not* carried over into the SDRC database file.  Only the distance and station power/ERP values are carried over.

 

Another observation regarding the FMLIST and MWLIST intermediate files.  In both files, the estimated signal strength is captured into the 14th data field, Column N, in terms of dB(?) units.  The higher dB levels take precedence in the secondary sorting that occurs in these files.  However, in the case of the FMLIST file, the dB values appear to always start with a small value and progress into negative dB values, whereas in the MWLIST intermediate file the signal strength has positive dB values.  For example, a strong 5.2 kW FM station that is located only about 2.5 miles (~4 km) from my house has a predicted signal strength of 1 dB in FMLIST while the subsequent entries for the same frequency are all negative values dropping down to -38 dB for the last entry (1 kW at 1428 km) for that frequency.  However, in the MWLIST intermediate file, all of the signal strength values appear to be positive, with a nearby moderate strength  AM BCB station (a station with an ERP of 1 kW at  a distance of 28 km) having a predicted strength of +72 dB, with the last entry for that frequency (a station with an ERP of 0.25 kW at a distance of 8190 km)  having a predicted signal level of +47 dB.  I realize that one cannot necessarily equate signal levels in SDRC to those in the database, but the nearby 5.2 kW FM station at 4 km away has an SDRC peak signal strength of -72 dBm (predicted  by fmscan.org at 1 dB) , while the 1 kW AM station 28 km away yields an SDRC signal of -53 dBm (predicted at +72 dB).  Clearly, there is a disconnect with how the predicted signal strength is calculated in each file.

 

Bottom line – I can’t seem to create an SDRC FrequencyDatabase.XML that lists station sin order of decreasing signal strength or increasing distance.  I’ll keep digging, but wanted to report the unsuccessful attempts thus far.  I guess I need to get a bit more aggressive in tweaking the SDRC database file.

 

Cheers,

 

Ken  -- WBØOCV

 

From: Ken Sejkora
Sent: Sunday, August 21, 2022 03:34 PM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Frequency Database Station Order

 

Thank you, Jim.  I know when you import data from fmscan.org, the SDRC database prefers ERP, but I don’t see how it gets used in the SDRC database.  The ‘Power’ column appears to reflect the station power in kilowatts rather than ERP.

 

I investigated the structure of the MWLIST and FMLIST csv files, and it appears the secondary sorting after frequency is based on the value in the 14th field (Column N).  Stronger stations have a higher value.  Perhaps one could re-sort the SDRC Frequency Database in a similar manner, but again, it doesn’t seem that the corresponding signal strength data are imported into the Frequency Database from the fmscan.org files.

 

Perhaps I’ll try to experiment with a Custom.CSV file to see if I can accomplish what I want.

 

Ken

 

From: Jim Smith G0OFE
Sent: Sunday, August 21, 2022 03:19 PM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Frequency Database Station Order

 

It has come up before... I remember asking if the list could be ordered by frequency then distance for VHF FM work - but I think I