Any correct interpretation of the Doppler effect disproves, explicitly or implicitly, Einstein's relativity. Professor Roger Barlow considers the case where the initially stationary observer starts moving towards the light source with speed v. The frequency the observer measures shifts from f=c/λ to f'=(c+v)/λ:
"Moving Observer. Now suppose the source is fixed but the observer is moving towards the source, with speed v. In time t, ct/λ waves pass a fixed point. A moving point adds another vt/λ. So f'=(c+v)/λ."
On the other hand, the speed of the light relative to the moving observer is
c' = λf'
Combining the two formulas gives
c' = c+v
in violation of Einstein's relativity.
Barlow's lecture quoted above introduces relativistic corrections (time dilation) and the frequency measured by the moving observer becomes
f' = γ(c+v)/λ
The speed of the light relative to the moving observer is, accordingly,
c' = λf' = γ(c+v)
Clearly, Einstein's relativity is violated even if the relativistic corrections are taken into account.
In order to prevent Divine Albert's Divine Theory from collapsing, Einsteinians, unlike Barlow, avoid the dangerous formula
f' = γ(c+v)/λ
and teach only the equivalent relation
f'/f = sqrt((1+v/c)/(1-v/c))
where the variation of the speed of light is somewhat hidden.
Here are explicit disprovals of Einstein's relativity:
"Let's say you, the observer, now move toward the source with velocity vo. You encounter more waves per unit time than you did before. Relative to you, the waves travel at a higher speed: v'=v+vo. The frequency of the waves you detect is higher, and is given by: f'=v'/λ=(v+vo)/λ."
"vo is the velocity of an observer moving towards the source. This velocity is independent of the motion of the source. Hence, the velocity of waves relative to the observer is c + vo. [...] The motion of an observer does not alter the wavelength. The increase in frequency is a result of the observer encountering more wavelengths in a given time."