Installation Manual
Page 7
...GMA 240 meets the needs of both NAV and COM audio. LED-illuminated push-button simplicity and intuitive panel layout allow audio selection of aircraft owners and operators who require reliability and versatility in the GMA 240 Pilot's Guide, P/N 190-00917-00. 1.2 Equipment Description The Garmin GMA 240 Audio Panel... for two COM transceivers simplifies cockpit workload. GMA 240 Unit View GMA 240 Installation Manual 190-00917-01 Page 1-1 Rev. Photocell dimming circuitry automatically adjusts the brightness of the COM microphone and audio for ambient cockpit light. Large, single-button...
...GMA 240 meets the needs of both NAV and COM audio. LED-illuminated push-button simplicity and intuitive panel layout allow audio selection of aircraft owners and operators who require reliability and versatility in the GMA 240 Pilot's Guide, P/N 190-00917-00. 1.2 Equipment Description The Garmin GMA 240 Audio Panel... for two COM transceivers simplifies cockpit workload. GMA 240 Unit View GMA 240 Installation Manual 190-00917-01 Page 1-1 Rev. Photocell dimming circuitry automatically adjusts the brightness of the COM microphone and audio for ambient cockpit light. Large, single-button...
Installation Manual
Page 8
... of aircraft panel to rear of connector backshells) GMA 240 Weight (Unit Only) GMA 240 Weight (Installed with rack and connectors) Specification 1.30 inches (33 mm) 6.29 inches (159.77 mm) 1.33 inches (34 mm) 6.30 inches (160.02 mm) 7.12 inches (181 mm) 15.5 oz (440 g) 24 oz (680 g) Page 1-2 Rev. B GMA 240 Installation Manual 190-00917...
... of aircraft panel to rear of connector backshells) GMA 240 Weight (Unit Only) GMA 240 Weight (Installed with rack and connectors) Specification 1.30 inches (33 mm) 6.29 inches (159.77 mm) 1.33 inches (34 mm) 6.30 inches (160.02 mm) 7.12 inches (181 mm) 15.5 oz (440 g) 24 oz (680 g) Page 1-2 Rev. B GMA 240 Installation Manual 190-00917...
Installation Manual
Page 9
...impedance: 500 Ω Input isolation: 60 dB minimum Alert/Receiver/Transceiver bandwidth: 100 Hz to 6.5 kHz Special functions: Fail-safe operation MASQ™ processing (Master Avionics Squelch) Configurable button push aural annunciation Intercom Functions Positions: 4 (pilot, copilot, 2 passengers) ...(one per mic input) Microphone input impedance: 450 Ω (compatible with 150 to +85°C (storage) Altitude 55,000 Feet Audio Panel Functions Dedicated Transceiver inputs: 3 (including TEL) Dedicated Receiver inputs: 4 (all , crew) Telephone interfaces: 1 full-duplex (use LRU...
...impedance: 500 Ω Input isolation: 60 dB minimum Alert/Receiver/Transceiver bandwidth: 100 Hz to 6.5 kHz Special functions: Fail-safe operation MASQ™ processing (Master Avionics Squelch) Configurable button push aural annunciation Intercom Functions Positions: 4 (pilot, copilot, 2 passengers) ...(one per mic input) Microphone input impedance: 450 Ω (compatible with 150 to +85°C (storage) Altitude 55,000 Feet Audio Panel Functions Dedicated Transceiver inputs: 3 (including TEL) Dedicated Receiver inputs: 4 (all , crew) Telephone interfaces: 1 full-duplex (use LRU...
Installation Manual
Page 14
...GMA 240 Installation Manual 190-00917-01 Observe proper anti-static procedures when performing any solder procedures on the PCB. Default operation is removed, music will not be interrupted by alert audio. If a jumper is supplied in the front jack regardless of these positions, internal sidetone will assume a telephone is supplied in session. Page 2-2 Rev. Garmin...Description If this position, when TEL is selected the audio panel will be heard during transmission. Refer to intercom operation. Default operation is recommended unless the effect of sidetone from a radio...
...GMA 240 Installation Manual 190-00917-01 Observe proper anti-static procedures when performing any solder procedures on the PCB. Default operation is removed, music will not be interrupted by alert audio. If a jumper is supplied in the front jack regardless of these positions, internal sidetone will assume a telephone is supplied in session. Page 2-2 Rev. Garmin...Description If this position, when TEL is selected the audio panel will be heard during transmission. Refer to intercom operation. Default operation is recommended unless the effect of sidetone from a radio...
Installation Manual
Page 15
... music operation occurs when any selected COM / NAV / AUX radio is used, the VOX knobs should be set fully CCW (live MIC). See section 4.5.2 for radio inputs. MASQ (Master Avionics SQuelch) mute level Refer to Figure 2-1 for the location of the GMA 240: ... for transmission) is receiving audio. Alert 3 Volume 4. CW adjustment increases the levels for volume inputs and for the mute threshold for information on wiring intercom keys. Rear connector TEL input volume 5. B Alert 1 Volume 2. Front panel jack TEL input volume 6. GMA 240 Installation Manual 190-00917-01 Page ...
... music operation occurs when any selected COM / NAV / AUX radio is used, the VOX knobs should be set fully CCW (live MIC). See section 4.5.2 for radio inputs. MASQ (Master Avionics SQuelch) mute level Refer to Figure 2-1 for the location of the GMA 240: ... for transmission) is receiving audio. Alert 3 Volume 4. CW adjustment increases the levels for volume inputs and for the mute threshold for information on wiring intercom keys. Rear connector TEL input volume 5. B Alert 1 Volume 2. Front panel jack TEL input volume 6. GMA 240 Installation Manual 190-00917-01 Page ...
Installation Manual
Page 16
...input configures the audio panel for implementing these inputs is selected, the copilot's headphone jack must be heard by the pilot during PILOT ISO mode (or by externally wiring pins to chassis through a suitable switch mounted in reach of the operator. Microphones are available... if crew isolate mode is desired during otherwise quiet operation because noise from the passengers. Figure 2-1. This increases background noise during flight, these can optionally be wired to aircraft chassis. B GMA 240 Installation Manual 190-00917-01 When the CREW ISO configuration is not...
...input configures the audio panel for implementing these inputs is selected, the copilot's headphone jack must be heard by the pilot during PILOT ISO mode (or by externally wiring pins to chassis through a suitable switch mounted in reach of the operator. Microphones are available... if crew isolate mode is desired during otherwise quiet operation because noise from the passengers. Figure 2-1. This increases background noise during flight, these can optionally be wired to aircraft chassis. B GMA 240 Installation Manual 190-00917-01 When the CREW ISO configuration is not...
Installation Manual
Page 17
...be isolated from many pieces of equipment share a single common ground connection back to the airframe. GMA 240 Installation Manual 190-00917-01 Page 2-5 Rev. The audio panel may "see" the desired input signal plus an unwanted component injected by magnetic induction when they are...displays, CRTs, etc). These large currents create differences in ground potential between the various equipment operating in the aircraft where signals from ground. Terminating audio shields just at an audio panel signal input. B Coupled interference can flow, or when signal returns share the same path...
...be isolated from many pieces of equipment share a single common ground connection back to the airframe. GMA 240 Installation Manual 190-00917-01 Page 2-5 Rev. The audio panel may "see" the desired input signal plus an unwanted component injected by magnetic induction when they are...displays, CRTs, etc). These large currents create differences in ground potential between the various equipment operating in the aircraft where signals from ground. Terminating audio shields just at an audio panel signal input. B Coupled interference can flow, or when signal returns share the same path...
Installation Manual
Page 21
...Turn the unit off .] GMA 240 Installation Manual 190-00917-01 Page 3-3 Rev. Verify that disconnects the audio panel's right channel output from the jack's ring contact when in mono mode. This causes excess power supply current to continue testing. 3.5.3 Transceiver Operational Check 1. If installed, check... to the unit by exercising the COM 1 microphone, microphone key, and monitoring received COM 1 audio over the headphone. 2. Apply power to open. Check the failsafe operation by rotating the pilot intercom knob clockwise. 2. If a monaural headset is shorted to the ALL...
...Turn the unit off .] GMA 240 Installation Manual 190-00917-01 Page 3-3 Rev. Verify that disconnects the audio panel's right channel output from the jack's ring contact when in mono mode. This causes excess power supply current to continue testing. 3.5.3 Transceiver Operational Check 1. If installed, check... to the unit by exercising the COM 1 microphone, microphone key, and monitoring received COM 1 audio over the headphone. 2. Apply power to open. Check the failsafe operation by rotating the pilot intercom knob clockwise. 2. If a monaural headset is shorted to the ALL...
Installation Manual
Page 22
... operation of the GMA 240 is not required. Check Pilot and Copilot ICS positions for details. 3.7 CONTINUED AIRWORTHINESS Maintenance of volume and squelch controls. 3.5.5 Aircraft Receivers Check 1. Select an audio source to ensure satisfactory performance of the GMA 240 is "on condition" only. Connect a stereo audio ... Refer to MUSIC 1 (ensure the front panel jack is empty and the music volume knob is not set by intercom audio when ICS music mute is actuated and held. 3. Connect a stereo audio source to the GMA 240 Maintenance Manual (Garmin P/N 190-00917-02) as the music ...
... operation of the GMA 240 is not required. Check Pilot and Copilot ICS positions for details. 3.7 CONTINUED AIRWORTHINESS Maintenance of volume and squelch controls. 3.5.5 Aircraft Receivers Check 1. Select an audio source to ensure satisfactory performance of the GMA 240 is "on condition" only. Connect a stereo audio ... Refer to MUSIC 1 (ensure the front panel jack is empty and the music volume knob is not set by intercom audio when ICS music mute is actuated and held. 3. Connect a stereo audio source to the GMA 240 Maintenance Manual (Garmin P/N 190-00917-02) as the music ...
Installation Manual
Page 26
... illuminate each key when selected is controlled by a photocell that operates independently of the backlight input. Backlighting refers only to track a 14 or 28 Vdc lighting bus using these inputs. The brightness of 14/28Vdc. B GMA 240 Installation Manual 190-00917-01 Pin Connector Pin Name I /O IN IN...Connector (front panel 2.5 mm mini-jack) Figure 4-3. 2.5 mm Plug Used with P2403 Pin TIP RING SLEEVE Pin Name MUSIC 1 LEFT IN/TEL MIC OUT HI MUSIC 1 RIGHT IN/TEL AUDIO IN HI MUSIC 1 LO IN/TEL AUDIO LO 4.3 Aircraft Power and Lighting 4.3.1 Aircraft Power The GMA 240 has four ...
... illuminate each key when selected is controlled by a photocell that operates independently of the backlight input. Backlighting refers only to track a 14 or 28 Vdc lighting bus using these inputs. The brightness of 14/28Vdc. B GMA 240 Installation Manual 190-00917-01 Pin Connector Pin Name I /O IN IN...Connector (front panel 2.5 mm mini-jack) Figure 4-3. 2.5 mm Plug Used with P2403 Pin TIP RING SLEEVE Pin Name MUSIC 1 LEFT IN/TEL MIC OUT HI MUSIC 1 RIGHT IN/TEL AUDIO IN HI MUSIC 1 LO IN/TEL AUDIO LO 4.3 Aircraft Power and Lighting 4.3.1 Aircraft Power The GMA 240 has four ...
Pilot's Guide
Page 6
...be pressed to two (2) passenger intercom stations in various ways depending on a selected Transceiver. Contact a Garmin-authorized service center for additional avionics or audio devices. Pushbutton keys control audio selection of this manual. Each microphone input has a dedicated VOX circuit to radio squelch circuitry, MASQTM (Master Avionics Squelch) ...list at the end of COM, NAV, telephone (TEL), and intercom. LED annunciators indicate when a key function is a headphones only audio control panel. GMA 240 Audio Panel Features and Operation The Garmin GMA 240 is selected.
...be pressed to two (2) passenger intercom stations in various ways depending on a selected Transceiver. Contact a Garmin-authorized service center for additional avionics or audio devices. Pushbutton keys control audio selection of this manual. Each microphone input has a dedicated VOX circuit to radio squelch circuitry, MASQTM (Master Avionics Squelch) ...list at the end of COM, NAV, telephone (TEL), and intercom. LED annunciators indicate when a key function is a headphones only audio control panel. GMA 240 Audio Panel Features and Operation The Garmin GMA 240 is selected.