[PATCH 2/2] New functions rtlsdr_set_tuner_bandwidth()

Alexander Kurpiers a.kurpiers at gmail.com
Wed Apr 15 13:29:11 UTC 2015

Hi Jiří,

On 04/14/2015 05:17 PM, Jiří Pinkava wrote:
> I have checked this when I was writing those patches, picked some
> information from it. But this implementations are rather hacks than
> clean implementations, but hanks for pointing out.

As long as you did not change the functionality... Leif did extensive
testing on the performance improvement on R820T. I don't think he is
keen on repeating all that.

At first sight it looks similar, but need to check more thoroughly.
> I does not implement listing of supported BW, would You considet this
> usefull function? (What to do in case BW can be selected from continous
> range?)

I already discussed with Leif internally before. There are good
arguments for both versions.
One being the fact that the gain is exported more or less same way
(rtlsdr_get_tuner_gains) and another that the calling software should
not need to know the tuner internals if possible.
But I do not have a strong opinion there.

The API is not really consistent. There are set and get functions that
try to set a given parameter and return the setting actually in use.
Then there is rtlsdr_get_tuner_gains() that returns a list of supported
And exotic functions like rtlsdr_set_tuner_if_gain() that only make
sense for E4000 knowing the internals.

Just by looking at the distribution, I think the first kind is the most
common - so maybe a rtlsdr_set_tuner_bandwidth() /
rtlsdr_get_tuner_bandwidth() [returning the bandwidth in use]?
But again: personally I do not mind (much).



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