Message-ID: <001b01c077a9$ecafdaa0$6bb21bca@xtr743187>
From: "Vernall" <vernall@xtra.co.nz>
To: rsgb_lf_group@blacksheep.org
References: <f7.652f049.27880aad@aol.com>
Subject: Re: LF: RE: Freq stability
Date: Sat, 6 Jan 2001 19:28:02 +1300
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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