[Hackrf-dev] feedback on lesson 1

[Joris]

Hi,

Hopefully it's ok to post some feedback on the SDR lesson 1.
All in all I was very pleased. The format and teacher make it
extremely accessible.


* If there are any good questions below or in the mailing list,
perhaps they can be converted into a "FAQ" on the lesson page?

* I like the current "production value", don't waste time polishing
them further.

* It might be worthwhile to refer in the same spot to the ("lesson
0"?) getting started documentation that exists already. I realise that
is not strictly the point of the lesson, but it might save some people
some frustration.

* The level of depth is just right for me. The "why" bits are the
point of the lesson, obviously. Do not shorten them - if anything,
they might be longer.

* Low pass filter: I may have missed it, but you emphasise the effects
for the CPU, but it's even more important for the listener (ie, no
noise).

* Low pass filter bis: why is the transition width 25? In playing
around I found that 90/10, 75/25 and even 50/50 seem to work fine?

* Low pass filter vs rational resampler: It seems there is a huge cpu
difference between doing the first decimation in the LPF vs doing
everything in the rational resampler. (my system can fun the former
just fine, the later is utterly unworkable). Is there no way to put
the decimation in a separate block?

* Perhaps it's a good idea to post a still screenshot of endpoint of
lesson 1. Posting the GRC file might be a good idea also, although it
might end up reducing tinkering.



Keep up the good work,
Joris