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Date: Wed, 10 Jan 2007 09:19:53 -0700
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Rod Pemberton wrote on Tue, 9 Jan 2007 at 03:46:03 -0500:

# I believe this it the math you'll need:
#
# 14.318Mhz=4*3.58Mhz=4*(4.5Mhz*455/572)
#     (4.5Mhz US TV bandwith/channel, 455 colorburst phase changes/line,
572
# total lines/frame including sync)
# 14.318Mhz/12=1.93182Mhz

Aha, this is the one that's why our numbers don't agree:
14.318MHz divided by 12 is actually 1.193666... MHz.

# 1.93182Mhz/65536=18.2065Hz

So it ends up being:

1.193666... MHz / 65536 = 18.20627848307291666... Hz