The two trace images to the left are both showing that signals from the Master Station A and Slave stations B and C are currently being received. The A pulse appears twice. Once at the far left hand side of each of the two lines.
The second pulse on the lower line right next to the A pulse is the ‘ghost’ pulse.
The ‘ghost’ pulse identifies that the preceding A pulse belongs on the lower line. (i.e. to the C transmitter)
The B pulse is the downward spike on the top line, whereas the C pulse is the downward spike on the lower line.The two little buckets are generated in the GEE indicator and need to be lined up, or ‘phased’ with the two spikes from the B and C transmitters.
We use the four front panel fine and coarse adjustment controls on the indicator unit to shift the little buckets either to the left or right until they line up with the inner left hand edge of the buckets.
This is not to easy to do accurately on this screen, so another setting is used, the strobe timebase, which makes the adjustment far easier, quicker and more accurately.