Re: AM demodulation

Hi Bill,

Look at https://wiki.gnuradio.org/index.php/PLL_Carrier_Tracking. I
think I will add this formula to the Notes: radians per sample = 2 * pi
* freq / sample rate

I don't know how wide a spectrum the PLL can handle.

I am working on the documentation of blocks, so let me know if there is
anything I need to add or clarify.

Cheers!
---
Barry Duggan KV4FV

P.S. I like the quote by Steve Sims :)

On 2019-10-28 10:44, Bill Dailey wrote:
> Can you give a little primer on using that PLL tracking? I would
> love to use that to just track carriers random frequencies. For
> instance 10mhz. Ultimately I want to track and periodically log and
> offset from true predicted frequency. Like every 10 seconds.
>
> Bill Dailey
>
> Negativity always wins the short game. But positivity wins the long
> game. - Gary Vaynerchuk
>
> Don't be easy to understand,
> Be impossible to misunderstand
> - Steve Sims
>
>> On Oct 28, 2019, at 9:27 AM, Barry Duggan <barry@dcsmail.net> wrote:
>>
>> Hi Albin and Volker,
>>
>> I added a PLL Carrier Tracking block to take care of the tuning
>> problem. See the revised
>> https://wiki.gnuradio.org/index.php/File:FunCube_AM.png
>>
>> Albin, that 'spike' is the carrier! This is AM ;)
>>
>> Thank you both for your suggestions.
>> ---
>> Barry Duggan KV4FV
>>
>>
>>> On 2019-10-27 07:13, Albin Stigö wrote:
>>> Hi Barry,
>>> Some thoughts:
>>> You have a large DC spike at the center, try using the frequency
>>> xlating
>>> fir filter to tune an offset frequency.
>>> Why don't you decimate at the channel filter?
>>> Try observing the signal at various points using the frequency sink.
>>> Good luck,
>>> Albin SM6WJM
>>>> On Sat, Oct 26, 2019, 21:02 Barry Duggan <barry@dcsmail.net> wrote:
>>>> Hi,
>>>> I've been working on a gnuradio AM broadcast receiver, and have
>>>> found
>>>> that the tuning is very critical to obtaining clear audio. My
>>>> flowgraph
>>>> can be seen at
>>>> https://wiki.gnuradio.org/index.php/File:FunCube_AM.png.
>>>> Are there any alternate demodulation methods which are not so
>>>> sensitive
>>>> to exact tuning?
>>>> Thanks,
>>>> --
>>>> Barry Duggan KV4FV
>>