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Re: buildd and buildbot




On Sunday 19 May 2019 07:42:23 pm Stefan Monnier wrote:

> > The klystron had one major flaw that proved Einstein was right when
> > he wrote E=MV2.
>
> Hmm... isn't E=MV² the kinetic formula from classical mechanics,
> whereas Einstein's similarly-sounding formula is E=MC² where speed
> doesn't enter the picture?
>
> > beam. So this beam was moving fast enough that E=MV** manifested
> > itself because the electron gained mass as you sped it up, and lost
> > mass as you
>
> AFAIK in those kinds of circuits, the speed of electrons is not really
> important: it's only marginally related to the speed of propagation of
> the signal and the frequency of the signal.
>
You should look at this on an ntsc waveform monitor that shows the 
resultant synch pulse after the dynamic change in group delay this 
effect introduces. One can adjust the sine-squared test pulse to look 
pretty good, but the dynamic change in group delay seriously rounds the 
leading edge corner of the sync, and will put a 30 "ire" down spike on 
the trailing edge of the sync.  And the synch itself is only 40 ire. 
Modern digital transmitters have grown compensating circuitry so they 
are buckets better in that regard because the hidef digital signal is 
much more sensitive. Turn that compensation off, and the digital may not 
get out of the transmitters front yard on 30kw up the pipe. Now days, 
for best distance, they monitor and compensate for that stuff in real 
time. The days of the 1960's when I checked and tuned it up in the wee 
hours of Friday mornings so I had a long weekend, just don't cut it for 
digital.

>         Stefan


Cheers, Gene Heskett
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