Date: Sat, 24 Nov 2012 21:01:41 -0330 (NST)
From: jcraig@mun.ca
To: rsgb_lf_group@blacksheep.org
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Subject: Re: LF: VO1NA at 20:00 - or not?
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Markus,

Thank-you for the very helpful information. It seems that achieving 
coherence is not at all difficult and a worthwhile project for the
future.

73
Joe

On Sat, 24 Nov 2012, Markus Vester wrote:

> Joe,
>
> thanks for the info. That must have been around sunset on your side... the signal then disappeared for a while and became again visible after midnight UT.
>
> Coherent keying would be beneficial as it generates a sharp central line in the spectrum which aids detection of below-noise QRSS or Opera signals. The source doesn't need to be referenced to GPS or similar, any stable oscillator will suffice as long as it is not interrupted by the keying. If you are now using a divider to drive the PA you would need to let the divider continue during key-up, and gate one of the subsequent driver stages instead.
>
> It is also possible to generate coherent FSK or DFCW but this requires careful adjustment of the symbol timing and frequncy shift so that df * dt is an integer number (as in WSPR or WSJT-X).
>
> Best 73,
> Markus (DF6NM)
>
>
>
> From: jcraig@mun.ca
> Sent: Saturday, November 24, 2012 3:11 AM
> To: rsgb_lf_group@blacksheep.org
> Subject: Re: LF: VO1NA at 20:00 - or not?
>
>
> Dear Markus, Group.
>
> Thank-you for the report.  Yes, VO1NA is on the air however there is still
> work needed towards achieving phase coherence keying!  The TX is a 100
> watt class E: an IRFP260N driven by a TC4427.
>
> Hopefully the Decca will be back in service soon.
>
> 73
> Joe
>
> On Fri, 23 Nov 2012, Markus Vester wrote:
>
>> Nice signals from the east (YO and AGC in red) and west (an early?blue NA on 137777), simultaneously in the TA window
>> http://www.alice-dsl.net/df6nm/grabber/Grabber.htm
>> ?
>>
>> Well at?least that's what I thought,?but no?trace?of VO1NA?yet on
>> http://www.w1vd.com/grabber.html
>> ?
>> Joe, are you on air?
>> ?
>> Best 73,
>> Markus (DF6NM)
>>
>> ?
>>
>>
>
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