[Discuss-gnuradio] correlation question

Hello all,

New to the list and Gnuradio. Been futzing around with a RTL/SDR and Hackrf. Have been receiving NOAA  APT transmissions. Have been working on analyzing the signal. Each frame starts with a 1040hz square wave for a sync pulse.

I've tried to teach myself correlation with a FIR filter to detect the sync pulse.

To this end I have a small sample flow graph that I think is correct and which just uses a vector source to generate a square wave to experiment with. The goal is just to verify I understand correlation in this context.

I have attached the flow graph to this email. If you could please let me know if I'm on the right track and if not what I need to change/correct.

Cheers,

Wayne Hilliard