Marker Beacon V+ Design

feature author: Paul Halliday 

There Marker Beacon worksheets were created since there are two Marker Beacon radios on the Beech 1900D. Since they are almost identical, only the first worksheet is described here. The MarkerBeacon1design is split into two parts: the Pilot Audio, shown in

Figure 44, and the CoPilot Audio, Figure 45. There is only one Marker Beacon Master Volume host input which was placed at the top of the Pilot Audio figure. This input is connected to a worksheet connector so that it can be used throughout the worksheet. The other inputs that come from the host are as follows.

• Pilot Audio Mkr Bcn 1 switch

• CoPilot Audio Mkr Bcn 1 switch

• Outer Marker 1 Signal Strength

• Middle Marker 1 Signal Strength

• Inner Marker 1 Signal Strength

The Pilot Audio Mkr Bcn 1 switch combines with the Outer Marker 1 Signal Strength and the Marker Beacon Master Volume to feed the volume of the Outer Marker player object. The Outer Marker 1 Signal Strength also goes through a Float to BOOL object, which then is fed to the enable pin of the Outer Marker player. The Outer Marker player plays a 400 Hz tone, pulsing at 300 milliseconds on, and 300 milliseconds off. This pulse is produced on the output pin labeled SIG. If you needed to synchronize the Outer Marker Beacon instrument panel light with the tone pulse, you could simply hook this pin up to a host interface output port, which would send it back to the host. We didn’t do that on the Beech 1900D because our Marker Beacon lights did not need to synch up with the tone. Hence, the SIG pin is hooked up to a No Connection object.

The Middle Marker player is hooked up much the same way as the Outer Marker player, only this time we used the Middle Marker 1 Signal Strength input. A Middle Marker player plays a 1300 Hz tone, pulsing at 100 milliseconds on, 100 milliseconds off, 300 milliseconds on, 100 milliseconds off, and so on.

The Inner Marker player is hooked up to the Inner Marker 1 Signal Strength input. A Inner Marker player plays a 3000 Hz tone, pulsing at 100 milliseconds on, and 100 milliseconds off.

The CoPilot Audio part of the worksheet is set up much the same way as the Pilot Audio part. It uses the CoPilot Audio Mkr Bcn 1 switch to determine if the CoPilot can hear the marker beacon radios.

Figure 44. Marker1 Design (Pilot)

Figure 45.Marker 1 Design (CoPilot)

A two-way interface with the SimPhonics computer wasn’t needed on the Beech 1900D simulator, but it could have been done if it had become necessary.