It’s been an S-Band weekend here. Earlier today the Indian Spacecraft MOM was picked up by DF2MZ as well as UHF-Satcom at a distance of 107 Million km! By the time the spacecraft rose over California Goldstone had locked it up to their ground station and data was being transferred. The signal was well down into the noise, but using some amount of integration the signal was detectable (as shown below). After a few hours Goldstone stopped the data transfer and unlocked the signal, the signal immediately increased in strength and moved to the calculated Doppler target, where it remained for the evening. You see Doppler in the locked signal because the spacecraft is compensating for the Doppler (locking to the ground signal), where on the unlocked signal you don’t see any Doppler, this is because it is being compensated with software using NASA Horizon data. The exact unlocked frequency was 2292.960847 MHz.
Here is a nice website that gives you the real time status of the DSN (click on image to go to the site).