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T channel TDI has opposite sign compared to Sangria

I generate the TDI signal in the following way,

tdisignal = lisa.GenerateLISATDISignal_SMBH(self.source, **waveform_params_smbh, Mfmax_model=0.2, input_freqgrid=input_freqgrid)
tdi = tdisignal['tdi'] 
mbh_tdi = tdi[(2,2)]

I read it through,

freq, phase, Ar, Ai, Er, Ei, Tr, Ti =  mbh_tdi['freq'], mbh_tdi['phase'], \
            mbh_tdi['amp_real_chan1'], mbh_tdi['amp_imag_chan1'], mbh_tdi['amp_real_chan2'], mbh_tdi['amp_imag_chan2'], \
                mbh_tdi['amp_real_chan3'], mbh_tdi['amp_imag_chan3']

so that I can plot the signal in time domain, after appropriate interpolations.

When comparing the Sangria data (label 2) and the template signal (label 1), I see, image

If I instead do,

freq, phase, Ar, Ai, Er, Ei, Tr, Ti =  mbh_tdi['freq'], mbh_tdi['phase'], \
            mbh_tdi['amp_real_chan1'], mbh_tdi['amp_imag_chan1'], mbh_tdi['amp_real_chan2'], mbh_tdi['amp_imag_chan2'], \
                - mbh_tdi['amp_real_chan3'], - mbh_tdi['amp_imag_chan3']

I have, image

This suggests a sign opposition in lisabeta compared to Sangria dataset.