Putting in zeroes in delta-Frequency in demodulators gives inconsistent results

[texasyojimbo]

Release: 3.8.2
Platform: Windows 10
Source: LimeSDR

Issue description: When I am using the AM demodulator and SSB demodulator, I will sometimes go to the delta-F box and start typing 0 (zero). Sometimes this sets the delta-F to 0,000,000.000 Hz. Other times it results in -9,551,616 Hz (and sometimes values in between depending on which significant digit is being edited). This may be present in others but hasn't been tested.

Reproduction steps:

1. Start SDRAngel

2. Set LimeSDR channel 0 as source.

3. Start streaming (doesn't matter whether NCO is on or off).

4. Add demodulator as sink

5. Click below the main frequency in the waterfall, delta-F in the demodulator will change automatically to correct value (negative).

6. Go to the delta-F box in the demodulator, click on the largest significant digit (MHz, left-most value).

7. Start typing zeroes.

8. delta-F will change to (negative) -9,551,616 Hz.

9. Zero out delta-F manually using arrow keys.

10. Click above the main frequency, delta-F will change automatically to correct value.

11. Go to the delta-F box in the demodulator, click on the largest significant digit.

12. Start typing zeroes.

13. delta-F will change to +0,000,000 Hz (correct value).

Let me know if you'd like screenshots or WebEx where I can demonstrate.

[texasyojimbo]

Changing decimation values does not seem to change value (always 9,551,661).
Screenshot attached

[f4exb]

Maybe a bug. Using number keys should not do anything. It is meant to be used with mouse or arrow keys.

[texasyojimbo]

Looking at the code (for ValueDialZ.cpp) I am going to go out on a limb here and suggest that there ought to be an absolute value used somewhere around line 580.

If I had more time to code and build, I would test this hypothesis.

[f4exb]

Firstly QChar('.') is (hard)coded in many places. This should be changed to the locale's group separator. This is in both ValueDial and ValueDialZ

Secondly only in ValueDialZ typing anything on the sign box or only the arrow keys should just flip it to the other possible value i.e. plus to minus or minus to plus.

Note: I just totally overlooked this part of code and didn't realize you can type in a number with the numeric keys. This is cool! This is old code coming from the base code of SDRangelove.

[f4exb]

Implemented in v3.8.4