THE GREEN BOX The Green Box generates useful tones such as COIN COLLECT, COIN RETURN, and RINGBACK. These are the tones that ACTS or the TSPS operator would send to the CO when appropriate. Unfortunately, the green box cannot be used at a fortress station, but must be used by the CALLED party. The tones (hz) are: COIN COLLECT 700 + 1100 COIN RETURN 1100 + 1700 RINGBACK 700 + 1700 Before the called party sends any of these tones, an operator released signal should be sent to alert the MF detectors at the CO. This can be done by sending 900 + 1500 Hz or a single 2600 Hz wink (90 ms) followed by a 60 ms gap and then the appropriate signal for at least 900 ms. Also, do not forget that the initial rate is collected shortly before the 3 minute period is up. ---------------------------------------