"http://CBC.am/" wrote:

Where are the DX hdtv recivers?



I should add that some DTV receivers, certainly the Samsung T-151,
will give you an indication that an ATSC signal is there
at a far lower C/N than is needed to decode it:

1) the green light will blink if you key in the channel

2) if you do a channel scan, it will pause several seconds
at any channel where an ATSC signal is present even if
it it too weak.

One more test: you can also design a circuit that will sync
onto the 5.375 mHz symbol clock in the demodulated baseband signal,
or even in the IF signal, at far less than the C/N needed to decode
it, but not as low as just seeing the carrier. This is of course
useful in doing an autocorellation, or a cross corellation with the
known 511 PN sequence.

Doug McDonald