[GreenKeys] using a scope for rtty

[tony j. podrasky]

Hey Eugene;

I have found a similar (same?) anomoly:

Instead of a perfect vertical and horizontal ellipse, mine
make an 850Hz shift look more like a 800Hz shift.

It seems to be the capacitance that the cable from the ST-6 to
the Scope adds.

If you feel like experimenting, try using some cable from your
stereo system or some plain old wire or clip leads. Don't use one for
both frequencies - use a separate one for each frequency and see
what that does.

Also, for some reason, my horizontal ellipse has a spike in the
middle. Destroys the beauty of what it should look like but makes
tuning nice because the spikes line up on the center line.

73,
W6ESE - tony
NNNNZCZC

Eugene Hertz wrote:
> Hi All,
> 
> Now that my rtty station is shaping up, I decided to pull out my tektronix
> 604 XY Monitor out of storage.  And I connected it to my ST6 and had a
> question.
> 
> Seems I was expecting a vertical ellipse and a horizontal ellipse
> corresponding to mark and space (or maybe space and mark, I forgot which is
> which).  However the horizontal was not quite horizontal and the vertical was
> not quite vertical!  The horizontal seemed to go up hill and the vertical had
> a similar angle.
> 
> Now, I took my precision digital function generator and programmed in 2125
> and 2295 so I know I'm putting in the right freqs.  So why is this so? Does
> this mean that my ST6 is not quite tuned properly? Does it mean my XY scope
> is off?
> 
> Thanks Eugene
> 
> 

-- 
Tony J. Podrasky | MicroSoft error messages written in Haiku:
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