PS Engineering PMA7000M-S Installation Manual - Manual (Page 26)

PS Engineering
PMA7000M-S Series Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-070-0012 Page 3-7 Rev. 12, Sept.2000
The Amber lamp, labeled "M," is the Middle Marker lamp and is coupled with a 1300 Hertz tone. It is
keyed alternately with short 'dot' and long 'dash' bursts at 95 combinations per minute.
The White lamp, labeled "I," is the Inner marker and has a 3000 Hertz 'dot' tone. The lamp and tone will be
keyed at a rate of six times per second.
The audio from the Marker Beacon Receiver can be heard by selecting the "MKR" push-button switch. To
adjust the volume level, there is a service adjustment located on the top of the unit. See Section 2.5
A three-position switch is used to set the receiver sensitivity and to test the indicator lamps. Use "HI" sen-
sitivity initially. This allows you to hear the outer marker beacon about a mile out. Then select the “LO”
sensitivity to give you a more accurate location of the Outer Marker. The momentary down switch position
is marker test, labeled "T/M" and illuminates all three lamps simultaneously to assure the lamps (internal
and external) are in working order. TST does not activate MM sense output.
In units with serial numbers above “F” series in the first set of numbers, a marker mute function was added.
Pressing the marker mode select down (to “T/M”) will cause the marker audio to mute for that beacon. The
next beacon received will re-activate the audio.
3.9 Internal Recorder System (Optional)
The Intercom Recording System (referred to here as the IRS) is a digital recording system allowing auto-
matic storage and playback of aircraft radio traffic.
Operating as a continuous loop recorder, (first message received will be the last heard), the recorder has one
minute of recording time or up to 16 messages. With its own built in VOX circuit, there are no buttons to
press to start recording. The system automatically begins to record the instant the radio becomes active.
Only aircraft radio audio in pilots headset is recorded and only the pilot will hear the playback audio.
3.9.1 Operation
Recording is automatic; there is no action required by the pilot. To play back the last recorded message,
simply press the momentary switch associated with the IRS. Each additional press of the button will play the
preceding recorded message. You must wait for the message to finish playing before accessing the prior
message.
To cancel the playback, press and hold the playback button for two seconds. The next time the button is
pressed, the next earlier message will be heard.
3.10 Audio Messaging system (Option 1, Option 2, only)
When this option is installed, the PMS7000M-S contains six stored messages. An outside annunciator, such
as an Electronics International engine gage system triggers these messages. When there is an announcement,
it will be repeated every two seconds until the remote- mounted ACK button is pushed. This stops the
played annunciation, until the next announcement is required (the next falling edge).
3.10.1 Concurrent Messages
When a recorded message or audio annunciation is playing, the other audio source is momentarily inhibited.
For instance, if an IRS message is being played, the audio annunciation will not begin until the IRS message
is finished. Conversely, the IRS recording cannot be played as long as there is an aural alert being played.
There is no recording made if playing a recording or annunciation.