Rb is actually one of the lowest phase noise reference sources you can
get - but really its all down to the OCXO used inside them. I
believe they have better short term stability than Caesium, and
certainly than GPSDOs.
But use at LF is going to be quite uncritical of short term
performance - the only thing that is going to matter is how accurate
it stays over periods of hours.
Andy G4JNT
On 3 December 2015 at 19:55, <[email protected]> wrote:
> Delighted that the message found its way to Italy and to
> at least one member of the Poldhu club!
>
> The discussion on Rb vs GPSDO is helpful, but I'm still undecided.
> It's rumoured that Rb has phase noise and needs new lamps from time
> to time.
>
> Thanks Edgar, Domencio, Markus, Paul and Andy.
>
> I'll try a longer message 39 characters, shorter symbols 0.5s and
> 8K19A starting 2000 UT.
>
> 73
> Joe VO1NA
>
>
> On Wed, 2 Dec 2015, Markus Vester wrote:
>
>> Indeed a strong signal (again)... hope the message will find it's way to
>> Italy tonight ;-)
>>
>> Attached is the symbols plot for the 22 UT transmission, which decoded at
>> 10.9 dB Eb/N0. On this small Win-10 convertible (Celeron 2x1.83 GHz),
>> running through the phase permutations for a 25 character decode takes about
>> 20 minutes.
>>
>> Good luck,
>> 73, Markus
>>
>>
>> -----Ursprüngliche Mitteilung-----
>> Von: jcraig <[email protected]>
>> An: rsgb_lf_group <[email protected]>
>> Verschickt: Mi, 2 Dez 2015 10:02 pm
>> Betreff: Re: LF: More EbNaut 137.777 - Dec. 1/2
>>
>> Hi Paul,
>>
>> That's very helpful. The oscillator needs some work to improve our
>> chances.
>>
>> In the mean time, how about a longer message, more power and shorter
>> symbols. 9K19A 1 Second symbols 25 characters 500 watts. 2100 UTC.
>>
>> 73
>> Joe
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