[OZAPRS] Calibration Signals

[Mark Jessop]

There is some software called 'LTE-Cell-Scanner' [1] which (funnily enough)
will search for LTE cells and give you PPM figures. Unfortunately the
repository is pretty much un-maintained, it has issues finding dependencies
(yay cmake), and it doesnt build without modifications on Raspbian. The
best information i've found on getting it running is this blog: [2]

Because I was somewhat bored this afternoon, I spent some time getting it
running under Raspbian (mainly based on the blog at [2]), and wrote up my
experiences here:
https://gist.github.com/darksidelemm/b517e6a9b821c50c170f1b9b7d65b824

As it turns out, my RTLSDR requires a PPM correction of about -2 PPM, so
not too bad!

Hopefully this is useful...

73
Mark VK5QI

[1] https://github.com/Evrytania/LTE-Cell-Scanner
[2] https://anthturner.com/2017/03/03/experiments-in-rf-hunting-for-lte/

On Sun, Nov 19, 2017 at 3:03 PM, <vk4tec at tech-software.net> wrote:

> 4G should be very good
>
>
>
> They have some of the best frequency and time standards
>
>
>
> They have to because of the CDMA modulation
>
>
>
> Andrew
>
>
>
> *From:* OZAPRS [mailto:ozaprs-bounces at aprs.net.au] *On Behalf Of *Gavin
> Rogers
> *Sent:* Sunday, 19 November 2017 2:27 PM
> *To:* Australian APRS Users <ozaprs at aprs.net.au>
> *Subject:* Re: [OZAPRS] How to make a raspberry pi satgate for the ISS
>
>
>
> Maybe different in other states, but in Perth the only carrier with GSM
> still is Vodadone, and their coverage isn't good enough where I am to get a
> good calibration.
>
>
> On 19 November 2017 11:21:49 am AWST, Peter VK2MPJ <vk2mpj at yahoo.com.au>
> wrote:
>
> I’m curious why you say that using kal and a GSM signal is not possible
> anymore?
>
> I did this locally just last weekend…
>
>
>
> 2MPJ
>
>
>
>
>
> On 19 Nov 2017, at 12:42 pm, Gavin Rogers <grogers at vk6hgr.echidna.id.au>
> wrote:
>
>
>
> On 19/11/2017 9:30 AM, vk4tec at tech-software.net wrote:
>
>
>
> Or, as i've mentioned before, just link to the existing Direwolf SDR+APRS
> guide, which covers off setting up an igate pretty well:
> https://github.com/wb2osz/direwolf/blob/master/
> doc/Raspberry-Pi-SDR-IGate.pdf
>
>
> In this guide, there's a link to a script that will tune to a NOAA
> frequency and re-calibrate an SDR TV stick ( https://github.com/khaytsus/
> direwolf-init )
>
> What would be a good high-stability signal source here in VK for the
> calibration? I used to use the kal program to calibrate against GSM
> transmitters, but that's not possible any more. I'd think the trunking
> control channel for an emergency services' channel would be stable, strong
> and always on? Or DAB+ transmitter, or..?
>
>
> 73
> Gavin.
>
>
>
> --
>
>
>
>       Gavin Rogers                     |  Amateur radio station VK6HGR
>
>     http://www.livingwaters.com/good   |     http://vk6hgr.ampr.org/
>
>                MSN/Skype/Email: grogers at vk6hgr.echidna.id.au
>
> _______________________________________________
> OZAPRS mailing list
> OZAPRS at aprs.net.au
> http://lists.aprs.net.au/mailman/listinfo/ozaprs
>
>
>
>
> --
> Gavin Rogers mobile
>
> _______________________________________________
> OZAPRS mailing list
> OZAPRS at aprs.net.au
> http://lists.aprs.net.au/mailman/listinfo/ozaprs
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.aprs.net.au/pipermail/ozaprs/attachments/20171119/34388deb/attachment.html>