Re: LF: what causes this on wspr

[Andy Talbot <andy.g4jnt@gmail.com>]

Yep - I missed the fact it was over a minute long .

The sidebands are 12Hz (not 8Hz as I said before) which seems a bit close for any synth instability.  Nothing is that slow surely.

So a bit of a mystery in that case.    Still reckon it looks like CW though.    Hard on -off keing generates a spectrum at harmonics of the clock frequency

Andy

On 1 July 2015 at 17:58, Graham <g8fzk@g8fzk.fsnet.co.uk> wrote:

Hi Andy

 

Problem there  is  it  lasts  , what  seems  to  be  the  full  duration  of the  data  phase  [ phase as  a change  from  cw  to data .. etc ]

 

wspr  via a  ssb  rig ,  overdriving  usually  produces  , harmonic  side  bands ,   1000  , 2000   Hz etc  Mains  Hum  50/100/150  etc 

 

The  power  distribution  looks like a  FM signal ,  that  would  also  account  for the  equal    distribution   about  the  centre  and the  extended  group  of  side  bands  to  the  right ..

 

I would  take   shot  at  a  kit  using   either  a  PLL    or   one  of the  clock  pulse  systems  .. with  timing  jitter  ?

 

73 -G,

From: Andy Talbot

Sent: Wednesday, July 01, 2015 5:33 PM

To: rsgb_lf_group@blacksheep.org

Subject: Re: LF: what causes this on wspr

Fast CW ident perhaps ?

The spectral lines look to be about 8Hz apart so that makes it 10 WPM or thereabouts

Andy  'jnt

On 1 July 2015 at 17:24, Graham <g8fzk@g8fzk.fsnet.co.uk> wrote:

what causes this  on wspr

 

This  takes  some  doing  ...... but  how  to  do  it  ?

 

G,