The formulae for the synchro standstill synchronizing torque, deriving from the analysis carried out on a transmitted-receiver synchro link in a previous paper entitled ‘Novel interpretation of synchro principles’ by N-Nagy and McNulty (1969) has been tested by experiments. Experiments were devised to measure the standstill synchronizing torque between two excited, interconnected synchros for rotor supply frequencies in the range 20–100 Hz and for a number of rotor supply voltages having complex waveforms of known frequency content. The measured experimental values were compared with values calculated using the formulae derived in the earlier paper above. This gave an indication of the accuracy and limitations of that new synchro theory.