Garmin GMA 240 Installation Manual - Page 16

Figure 2-1. Access Hole Location (Top View) 2.3.3 Hardwire Configuration Option The following configuration options are available by externally wiring pins to aircraft chassis. When change of operation is desired during flight, these can optionally be wired to chassis through a suitable switch mounted in reach of the operator. See Section 4.4.1 for connector and pin details for implementing these configuration options. MASQ™ INHIBIT: The Master Avionics SQuelch inhibit configuration option allows selected avionics audio inputs (COM, NAV, AUX) and alerts to be heard even if they do not exceed the MASQ threshold. This increases background noise during otherwise quiet operation because noise from these inputs is not squelched. This option is most useful as a troubleshooting tool. CREW ISO: This input configures the audio panel for crew intercom isolation in place of pilot isolation. When the PILOT ISO key is selected, the pilot and copilot will hear each other but will be isolated from the passengers. When the CREW ISO configuration is selected, the copilot's headphone jack must be wired in parallel with the pilot headset output. Microphones are wired as normal. PILOT ISO MUSIC: This input configures music to be heard by the pilot during PILOT ISO mode (or by the pilot and copilot if crew isolate mode is configured). Normally, the isolated ICS positions do not hear music. Page 2-4 Rev. B GMA 240 Installation Manual 190-00917-01