[chirp_users] Column Differences

[Tom Hayward]

On Wed, Feb 10, 2016 at 12:01 PM, Walt Childson <wchildson at gmail.com> wrote:
> There are some new columns in the Img file but those columns do not get
> generated in CSV.
>
> In general the IMG columns, the memory Properties column list, the CSV
> columns and the WiKi column definitions are not in sync.
>
> I especially would like to use the Power column.

Hi Walt,

The differences you are seeing between CSV and .img files are due to
the differences between radio models.

Chirp .img files are the exact contents of a radio's memory as
downloaded by Chirp. This means they will be different for every radio
and will only support the features of that radio. Some radios support
power settings per channel, some do not, so availability of this
column will vary by radio model. Likewise, Dstar columns are only
available for Dstar radios, etc.

Chirp CSV is meant to be a least-common-denominator format. For the
most part, it contains columns supported by all radios. Not all radios
support power settings, and for those that do there is no standard*,
so CSV does not support a power level column. Not all radios support
"priority" scanning (and this means different things for different
radios), so this is intentionally left out of Chirp CSV format.

*When I say there is no standard for power levels, I mean that "low"
and "high" mean completely different things on different radios. Low
power can mean anything from 50 mW to 10 watts, depending on the
radio. High power could mean anything from 5 watts to 100 watts or
more. It gets even more complicated when you add in power levels like
"Mid", "Medium", "L2", "L3", etc.

Chirp's import/export/copy/paste features attempt to disambiguate
these power levels by assigning a value in watts to each power level
in every radio that supports power levels. If you copy a "high" power
radio channel from a handheld and paste it into mobile, Chirp looks up
what "high" means for that handheld--typically 5 watts--then attempts
to find the closest power level to 5 watts on the mobile--probably
"low" power. Since CSV format is not tied to a specific radio, there's
no good baseline power levels to choose from, so it just isn't
supported.

Adding an unsupported column to a CSV file will not add support for
that column in Chirp. You would also need to add the column in the
Chirp code and write code for how to interpret that column. This code
would be relatively simple to write if not for the problem I mentioned
above--you would need to define how to disambiguate all the possible
options.

Tom KD7LXL