Direction Finding and linking existing KiwiSDRs

jks

Okay, v1.197 is out. Restart to get it immediately. See the change log file: https://github.com/jks-prv/Beagle_SDR_GPS/blob/master/CHANGE_LOG
Don't forget that you can save yourself a little time by creating a bookmark that auto-launches the extension, e.g.
http://kiwisdr.jks.com:8073/?f=77.5iqz10&pbw=1000&ext=tdoa

W1EUJ

Got updated. Not seeing my Kiwi on the map though?

jks

Give it 20 minutes or so to show up. I will improve this later on, but the issue is that your Kiwi reports its status to kiwisdr.com every 15 minutes. But when the first report goes out after a restart the GPS is unlikely to have acquired enough sats to meet the minimum requirement to be listed on the TDoA map. So you end up waiting 15 minutes for the next reporting period to be listed. It's on the bug list..

jks

I see you listed, but it's another issue. Right now your map marker is labeled "Kiwi63". Mouse-over the marker and you'll see your Kiwi name description of "0-30 MHZ KiwiSDR - Outside Boston MA USA" appear.

This is because the map marker labels are derived from trying to guess if there is a callsign present in the "Name" field on the sdr.hu tab of the Kiwi's admin configuration. Yours doesn't contain your call, so the label defaults to "KiwiNNN". But note there is now a new field in the sdr.hu tab called "TDoA id". A entry here is shown directly on the marker label. You will have to wait a while before a change shows up on the map (similar problem to above).

Your call is present in your Kiwi's URL, so I suppose I could also try extracting a callsign from there.

G8JNJ

Hi John,

Yes, I am using the 'scissors' but sometimes the list still filled from near the bottom.

Some good successes today with testing using the UK Volmet transmissions on 5450KHz and 11254KHz both of which seem to be transmitting from Inskip https://en.wikipedia.org/wiki/RNAS_Inskip_(HMS_Nightjar) (middle of the UK) today, but can also be from St Eval https://en.wikipedia.org/wiki/RAF_St_Eval in Cornwall (SW tip of the UK)









Very well done to all concerned.

All we need now are some KiWi's with decent antennas and a working GPS in some of the more outlying parts of the world :-)

Regards,

Martin - G8JNJ

jks

Thanks Martin for the clarification. I'll keep trying to replicate the problem here. Clicking on a new station is supposed to enter it into the first available (i.e. blank) field from the top.

G8JNJ

Hi John,

Here's a picture



I think the sampling period maybe either needs to time out or a stop button should be added ?

Sometimes it just continues and the only way to stop it is to close the extension and restart it.

Likewise sometimes the processing takes forever and it's clear that it's not going to work as at least one of the captured signals is of too poor a quality.

Incidentally, I've also noticed that when using Chrome on an iPad the admin screens only display the top line and not the main content (just white) and also the pop out Ant_Switch extension will not display once the TDoA extension has been used, but can be restored with a refresh. I seem to recall that some of these issues have been seen before.

Regards,

Martin

W1EUJ

@jks I went thru the same process to figure the same at about the same time, almost down to the sentence. TDoA ID entered, that works well, it allows to cut down and tailor the marker name to TDoA needs but keep the sdr.hu name what it needs to be - which for me is to highlight my Kiwi for the Boston area folks. Thanks again!

G8JNJ

Hi John,

A couple of problems using Chrome on Win7 Pro 64 bit.

First another variation on the list filling from the bottom




Second, I've found that once I've run and completed a TDoA session, I have to refresh the browser and open the TDoA extension afresh then setup all the SDR's again, otherwise when I run a second TDoA the 'sampling started' indicators just continuously run and never stop.

Just clearing the SDR's from the list or closing and reopening the TDoA extension doesn't fix it.

This may be due to stored values from the first run not being flushed out, or perhaps some of the SDR's are no longer available ?

If I do a complete refresh, it generally works constantly every time.

Regards,

Martin - G8JNJ

W1EUJ

@G8JNJ @jks I found that when you see the list filling out partway down, that clicking on the scissors of the top 'empty' slots clears them for entry. FWIW.

G8JNJ

Yes, I tried that but it doesn't work for me, I still can't enter anything towards the top, even if I click on the top entry box to try and select it.

Regards,

Martin - G8JNJ

WA2ZKD

what is the criteria for stations appearing on the map? I "thought" mine was on there, now gone (?)

W1EUJ

I notice that you're 3/4 channels in use and the remaining one is password access only. Wonder if when you are in that state you drop off the list?

WA2ZKD

not sure when that PW got set, wasn't intentional

jks

@Martin The code isn't very robust yet against the various processing steps getting stuck or terminating without returning proper status. For example if the kiwirecorder run launched by the kiwisdr.com server doesn't act as expected there is no timeout detection. If you're zoomed out too far then the Octave TDoA process will run for a long time generating the long coastlines for the maps. There needs to be an abort/reset button and the associated cleanup.

@Jim Your Kiwi reports its status to kiwisdr.com every 15 minutes. A database is updated which is then used to build the kiwisdr.com/public page and is also used by the http://rx.linkfanel.net map. If your Kiwi has received no GPS fixes during the previous minute at the time of the report then it is removed from the database and will not be checked again until the next 15 minute reporting period. The period and the criteria are simply what was convenient at the time. With more work it could be changed.

WA2ZKD

Does the kiwi "announce" itself before the first fix or does it delay a bit? I see TFF values of < 1 minute on any kiwi I have with GPS

jks

Immediately so as to get listed on sdr.hu etc. asap. What I'll do is change it to send another announce on the first fix.

WA2ZKD

perfect!

jks

v1.198 should list your GPS-enabled Kiwi more quickly on the TDoA map after a restart.

jks

Please open new discussions in the new "TDoA topics" category. This thread has 80+ comments now and covers multiple TDoA aspects. That makes it less useful for people searching for information in the future.