Re: [Discuss-gnuradio] ATSC Magic coupling constant

[Andrew Davis]

Hello All,

Just an update for those following along, I have ( somewhat ) finished the ATSC transmitter, most of the blocks needed were all ready made, but they stopped right before pilot insertion and VSB modulation ( my guess is since the hardware back then was receive only they stopped there ), so I added the needed blocks, and transmitted with my USRP1 to a television. It is much faster than real time and so i'm trying to encode and transmit my webcam live but i'm still working on getting gstreamer to output the correct stream :)

Also the receiver is coming along but i'm still stuck with the magic constant. I have a nice sample data recording from my USRP of my local TV station, it is just above the threshold for decent recovery and so should be good for testing improvements the the receiver. Would anyone like this sample for testing?

Thank you all

Andrew

On Wed, Jul 31, 2013 at 5:00 PM, Andrew Davis <address@hidden> wrote:

Ok, I tried the off by sqrt(2) and it put me close but now the bit_timing _loop is running short on data again, which as a disseminator means it probably cant find a good sync for timing and just eats all its input samples. So I pushed my changes to where i'm at now to github, could you see if that compiles for you, then I could walk you though whats all going on with this and where i'm at.

Thank you

Andrew

On Tue, Jul 30, 2013 at 8:12 PM, Johnathan Corgan <address@hidden> wrote:

On 07/30/2013 04:28 PM, Andrew Davis wrote:

> Thanks for the idea, I will try it tomorrow when I get back to the test
> machine ( which is powerful enough to be within reach of real-time
> decoding if I get this figured out :)

If you don't get this straightened out, I'd be happy to work with you by
phone or chat.

--
Johnathan Corgan, Corgan Labs
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