According to Viljo Allik in Estonia “I did another ISEE-3 receive test today. Results are added to the previous files here: http://193.40.1.117/public/p_DSN/ISEE3/ In the demodulated signal spectrum of the the last images it is possible to see the doppler shift caused by spacecraft rotation.”
Detection of ISEE-3 With a 4.5 Meter Dish in Estonia, earlier post