A light source emits equidistant pulses and an observer/receiver starts moving towards the source with speed v:
https://www.einstein-online.info/wp-content/uploads/SRT_Dopplereffekt_Pulse_4_%C2%A9_Daniela_Leitner_Markus_Poessel_Einstein-Online.gif
The speed of the light pulses relative to the observer shifts from c to c'=c+v, in violation of Einstein's relativity, and the frequency at the observer shifts from f=c/d to f'=c'/d.
The speed of the pulses relative to the observer will remain constant, c'=c, and Einstein's relativity will be saved, if the motion of the observer somehow shifts the distance between the pulses from d to d'=dc/(c+v). This is the ONLY way to save relativity, in accordance with the formula
(frequency) = (speed of light)/(distance between pulses)
The problem is that the shift from d to d'=dc/(c+v) is just as obviously idiotic as Big Brother's 2+2=5.
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