On 6 Oct 2009 at 14:17, Roman RW3ADB wrote:
> G'day Steve.
>
> * VK2ZTO <[email protected]> [Tue, 6 Oct 2009 19:15:34 +1100]:
> > G'day All,
> >
> > I had a look at the RW3ADB grabber and I see exactly the same
> > characteristic
> > signal here in VK-land on 499,993 Hz. Can't think what it might be.
> >
> > Sometimes it looks like one or two second dots and sometimes it looks
> > continuous.
> >
> > Attached are two comparisons.
> >
> > Any clues ?
>
>
> Two variants Steve:
> 1) Russian Army use an IF 500Kc. May be a heterodynes signals. But how
> is rx'd in AU? ) 2) Pulse-Power converters.
Or more likely the 32nd harmonic of the 15.625kHz TV line ocillator
rate. UK, UA and VK all use the 625 line PAL standard (though parts of
USSR are Secam). The line rate is actually locked to the colour
subcarrier of 4.43361875 MHz which may account for the 7Hz shift at
500kHz.
73 Dave G3YMC
http://www.davesergeant.com
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