Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Tighten transition band when tuner bandwidth is narrow #166

Closed
wants to merge 1 commit into from

Conversation

mossmann
Copy link
Contributor

Let's say, hypothetically speaking, you wanted to use the derived frequency plot on one of the 300 baud carriers of a V.21 modem connection captured at 44100 samples per second. The channel bandwidth is very narrow compared to the sample rate, so the adjacent channel interferes with demodulation due to the fixed transition bandwidth of the tuner filter. This patch makes the transition bandwidth equal to the cutoff frequency when the tuner bandwidth is narrow and leaves things unchanged when the tuner bandwidth is wide.

@miek
Copy link
Owner

miek commented May 27, 2020

What a coincidence! I had been wondering about just such a hypothetical situation too. I think this change would solve that sort of problem very well, thank you!
Merged, along with the real-samples branch in case that might be useful too in such a situation.

@miek miek closed this May 27, 2020
@miek
Copy link
Owner

miek commented May 27, 2020

Also, 6797a24 should help make the frequency plot more readable for narrow bandwidths.

@mossmann mossmann deleted the transition-band branch May 27, 2020 14:29
@mossmann
Copy link
Contributor Author

Oh, nice! I actually attempted 6797a24 myself, but the right way to do it eluded me.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

Successfully merging this pull request may close these issues.

2 participants