The underlying function used for calculating Latitude and Longitude -also used in other places inside the radiosonde app- was returning a positive value always.
But it needs to cope with negative values also (i.e. Lat and Lon)
Fixed by just changing the returning value into int32_t (even if the calculation is done in uint32_t, the actual sign is passed thru when returning the calculated value -those are the same 4 bytes, interpreted either as (before) unsigned or (now) signed)
I think the Jammer deserves a green icon, since it actually does it job pretty well.
Then there is a Jitter parameter. It allows to introduce a jitter from 1/60th of a second up to 60/60th of a second (a full one). It will delay / move forward either the TX or the cooldown period for a maximum of a half of the time you choose as jitter.
Meaning: If I choose 60/60th, a full second of jitter, it will produce a random number from 1 to 60.
Then it will calculate jitter = 30 - randomnumber
THen it will "add" that (positive or negative) time to the time counter for the next jitter change of state.
Discord User jteich did some investigation (Thanks!) and helped me understanding this rather obscure parameter:
Internally, is called "TRIGGER", and is passed into the baseband when configuring the desired spectrum sample rate.
Please forgive me in advance if this explanation is not 100% correct. It's only my interpretation, based on my own observation and jteich's comments over Discord chat.
This trigger parameter apparently determines the amount of data over time used for calculating the signal's power inside each specttrum's bin, before considering it "done".
In short, if you lower this resolution value then the cascade will tend to be rendered a bit faster, while kind of blind to tiny signals.
On the other hand, a bigger value will help rendering and distinguishing different signals on the cascade.
Too big a value can easily clutter up the cascade. But then it may be a "blessing" when inspecting higher freuqencies -where hackrf is more deaf"
The default value of 32 is quite decent. But then, now you can experiment with it. Cheers
Added a PRESETS.TXT file (inside /LOOKINGGLASS folder).
Also optimized the way the spectrum signal is integrated into the cascade.
Added provision for ranges lower than 240MHz but I am afraid that at this time it will not be advisable to lower ranges any more than 240MHz, since some artifacts and frequency running - moving out of place- occurs.
I can only hope that someone with a better understanding of hackrf's inner code can fix this issue and perhaps enhance the scanning speed.
I found some "original commenting" inside the code:
// TODO: Move more low-level radio control stuff to M4. It'll enable tighter
// synchronization for things like wideband (sweeping) spectrum analysis, and
// protocols that need quick RX/TX turn-around.
Which makes me think that there are things "missing" from the portapack side of the code, for allowing serious speed sweeping. So I am concluding that with current "portapack framework" this might be "the best possible thing".
It is to be noted that the "new" internal sweep mode code is signed by:
* Copyright 2016 Mike Walters, Dominic Spill
*
* This file is part of HackRF.
Maybe Mike or Dominic can be contacted and hopefully lend a hand on enhancing this code.
