Re: LF: K7PO testing 8270.0

[Markus Vester <markusvester@aol.com>]

Compliments to Ward, Jay, as well as Mike and Paul. Great work!

As Stefan says, it may not always be easy to avoid subtle couplings from the 1pps fed to one soundcard channel into the receive antenna circuitry on the other channel. The problem is clearly visible on my 21 uHz spectrogram at home. But a large 0.1 Hz offset would put you out of range of many already running grabbers, so I'd tend to stay within a couple of milliHz of 8270 Hz.

Best 73,
Markus  



-----Ursprüngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Do, 22. Feb 2018 10:18
Betreff: Re: LF: K7PO testing 8270.0

Jay, Ward,

Be careful, it could be that your GPS 1 PPS leaves a 'fence' of 1 Hz sidebands in your signal stream, at least when looking deeply into the noise. To avoid this, it is sometimes better to avoid transmitting on integer Hz frequencies.

Currently VO1NA is transmitting on 8270.0075 Hz.
DK7FC is transmitting on 8270.1 Hz.
Maybe it is helpful if Ward moves a bit away from 8270.000 Hz, e.g. 0.1 Hz down, to avoid interferences from and to VO1NA. This way you can exclude the eventuality that someone detects his own 1PPS signal instead of your carrier.

73, Stefan

Am 22.02.2018 05:33, schrieb jrusgrove@comcast.net:

Ward

 

A later file produced a better Carrier S/N of 14.65 dB in 35.2 uHz. Daytime files did not produce a decode of the carrier.  

 

Jay W1VD  WD2XNS  WE2XGR/2