[Talk-ca] Callsigns...

James Ewen ve6srv at gmail.com
Mon Mar 11 15:42:43 UTC 2013

On Mon, Mar 11, 2013 at 5:15 AM, Harald Kliems <kliems at gmail.com> wrote:

> As there already is a database available with the relevant
> information, I'd voice my usual objections towards importing this data
> into OSM. The data is not verifiable on the ground (well, I guess it
> theoretically is if you had appropriate measuring equipment, but
> still...)

Since Colin is talking about the broadcasters, it is pretty easy to
have appropriate equipment to verify the frequency... a TV or radio
will do that. You can locate the source with a little more equipment,
like a directional antenna, and some attenuation. You can get the
owner and callsign from listening to the broadcast.

Power levels are a little harder to determine remotely though.

> and probably changes somewhat frequently, making the data in
> OSM difficult to maintain properly.

The local TV and radio stations in my area don't change frequency very
often. Many of the radio stations have been on the same frequency and
callsign for decades. TV frequencies changed recently due to new
regulations, but before that they too were static for many decades.

Even when you get into commercial radio the frequencies and callsigns
don't change often. Changing a frequency on a radio repeater means
changing all the users on that system, a task that isn't undertaken on
a whim. Industry Canada assigns the frequencies to the users, and it
is a bit of a bear to change frequency assignments.

> So I don't see the added benefit
> of having the data in OSM.

It's one of those things where the data is of interest to some people
and not others.

I work in commercial radio, and I have thought about adding radio
towers to the database, with frequency assignments etc. It would be
very handy for my purposes. My employer might not like me posting all
of our frequencies and tower locations though... Not really sure since
Spectrum Direct allows people to look up the information anyway.

It is always difficult to know what information is of benefit to the
OSM database as that is a subjective judgement call. Addresses might
be of little use to some users, yet they still are being added to the
database. Does their inclusion "benefit" the database? What percentage
of potential users need to require the data before it becomes a

If the data is not included in the database, then potential users of
the data won't look at the OSM dataset as a source. If however the
data is included in the database, potential new users may be drawn to
the dataset.

It's the old chicken vs. the egg situation, a catch-22.


More information about the Talk-ca mailing list