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Re: VK2KU Notes

Hi Edward,

> Also I clicked on the Timf2 Oscope.  How do it shut it off? 
Click the button once more.

In case you can not find it because the timf2 oscilloscope
writes tracks on top of it, you could move the high resolution 
graph to the right hand part of the screen because there is
likely some part of its left hand side that you could grab.

Another way is to edit the file par_xx_hg (xx is processing mode)
and change the line:
timf2 display [1]
timf2 display [0]

> I guess 
> you have to calibrate the filters with a test signal as I have "Not 
> calibrated printed on the main waterfall display.  I do not have 
> access to a square wave generator - will a sine wave work?
NO. But you could easily convert from sine to square-wave
with a schmitt trigger (74xx14) or make a bistable multivibrator
with 74xx122 or a pair of 74xx04. There is no need for phase
stability, but VCC has to be extremely well decoupled because
any noise on it will be on the output 50% of the time. 

The square-wave has to have a duty that is reasonably close
to 50%. I can not tell exactly right now, but probably it has 
to be within the range 40% to 60%.



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