John,
Wish we did have access, though; 15625 being 1MHz divided by 64 is a
beautiful thing! In the American system, our sync-to-standard-frequency
ratios are a little messier. The color burst frequency is defined as
63/88ths of precisely 5MHz, with horizontal sync being 2/455ths of color
frequency. Lovely combination of ratios, eh?
73,
John KD4IDY
The integer numeric relationship is for PAL line frequency. PAL colour
subcarrier is also a deliberately interleaved frequency with a 25 Hz offset,
so is another "lovely combination" and hardly suited for direct locking to a
standard 5 or 10 MHz oscillator.
I'm not sure if there is any German satellite TV downunder, but there is a
terrestrial German UHF channel here in Wellington, with international
programme content, so it could be reticulated by satellite?
Of course, another factor with using an off-air radio signal as a frequency
reference is that the receiver would not want to be interfered with by any
on-site amateur transmission, especially if it was used to lock the
frequency of that transmitter :-)
73, Bob
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