Operation

The M1064 works with a feature button. Program the bottom right button (#24) on the 6424 set for the call-timer. When the led associated with this button is illuminated, the M1064 activates audio transmission on the Radio jack. It provides a short as an off-hook indication.
The M1064 also works without the feature button by receiving a short on pair 3 of the Radio jack from an external source. This will put the set in an off-hook state.

Connections

Two connections are made at the 6424 line cord input jack. 48vdc power for the M1064 is derived from pair 4. Power is not polarity sensitive. The recorder audio is transformer coupled to pair 2.

• Line jack
  1. Pair 2  =  recorder audio
  2. Pair 4  =  48vdc power

• Radio jack
  1. Pair 1  =  600 ohm transmit audio  (input)
  2. Pair 2  =  600 ohm receive audio  (output)
  3. Pair 3  =  off-hook closure  (input)

     Pin 3 = +
     Pin 6 = -

  4. Pair 4  =  off-hook closure  (output)

     Pin 7 = -
     Pin 8 = +

Beep tone

The beep tone generator produces a 200ms 1400hz tone every 15 seconds. The tone is audible to both parties. It can be turned on or off with the beep tone switch, located beside the Radio jack on the back of the set.
Move the switch to the right to turn the tone off. Moving the switch to the left enables the beep tone.

Rear view of the 6424D+ terminal showing the radio jack and beep tone switch.

Limitations

During speaker-phone use, the Radio jack interface becomes unusable. Record audio and optional beep tone are still provided for the speaker-phone.

Power

The M1064 requires 48vdc aux power at 10ma.