background image

22

en | Maintenance

Airman 850

09-2021 | V07 | F.01U.264.819

Customer maintenance manual

Bosch Security Systems LLC

RED

GREEN

COPPER

Figure 6.3: 

Airman 850 headset, boom assembly reference view

Red Wire

Green Wire

Copper Wire

Vcc = 3.3V

V out

Ground

DEVICE UNDER TEST

3.

Follow the steps 4 through 8 in 

Microphone / amplifier sensitivity check, page 20, and

then measure the output of the boom microphone. The output should be 24 mVRMS ± 7
mV

i

Notice!

If the output does not fall within the tolerances, adjust the gain pot as shown in the previous
illustration.
This test is not designed for absolute accuracy, but rather to tell if the boom assembly is
functioning properly.
If no output or no acceptable output is obtainable, then replace the boom assembly.

Testing the Circuit board assembly

To test the circuit board assembly, do the following:
1.

Construct a test circuit. For more information, see illustration below.

2.

Connect the circuit board to the test circuit.

With 

Vin

 measuring 100 mVRMS 1 Khz,

V out

 should read 210 mVRMS ±60 mV.

If the output is outside this range, replace the circuit board.

12 Vdc

25uf
25 Vdc

220

V OUT

J8

J9

J2

J3

25uf

+

V IN

600

470

1/2W

DEVICE UNDER
TEST

Figure 6.4: 

Airman 850 headset, circuit board test diagram

Summary of Contents for Airman 850

Page 1: ...Airman 850 AIRMAN 850 Headset en Customer maintenance manual ...

Page 2: ......

Page 3: ...0 002 003 101 and 400 16 5 2 Airman 850 wiring diagram catalog numbers 301317 200 201 and 300 17 5 3 Connector views wiring diagrams 18 5 3 1 Connector view for catalog numbers 301317 000 003 200 300 and 400 18 5 3 2 Connector view for catalog numbers 301317 101 and 201 18 5 3 3 Connector view for catalog number 301317 002 18 5 3 4 Connector wiring diagram for catalog numbers 301317 000 003 101 20...

Page 4: ...4 en Table of contents Airman 850 09 2021 V07 F 01U 264 819 Customer maintenance manual Bosch Security Systems LLC 9 Appendices 31 ...

Page 5: ...nclude all information concerning problem and mail to Bosch Communications LLC 8601 Cornhusker Hwy Lincoln NE 68506 U S A Attn Aircraft Product Support Mgr Telephone 877 863 4188 1 3 Parts ordering Replacement parts may be ordered from our parts department When ordering please include the following information Model number Part description Part number Quantity Mail to Bosch Communications Inc 8601...

Page 6: ...cription ANR Connector and wiring used 301317 000 Airman 850 Headset Dual sided Yes PJ 068 or equivalent PJ 055 or equivalent Connector wiring diagram for catalog numbers 301317 000 003 101 200 201 300 and 400 page 18 301317 002 Airman 850 Headset Dual sided Yes XLR Connector wiring diagram for catalog number 301317 002 5 pin XLR page 19 301317 003 Airman 850 Headset Dual sided Yes PJ 068 or equiv...

Page 7: ...Single sided Yes PJ 068 or equivalent PJ 055 or equivalent Connector wiring diagram for catalog numbers 301317 000 003 101 200 201 300 and 400 page 18 301317 400 Airman 850 Headset Dual sided customer specific Yes PJ 068 or equivalent PJ 055 or equivalent Connector wiring diagram for catalog numbers 301317 000 003 101 200 201 300 and 400 page 18 Refer to Connector views wiring diagrams page 18 ...

Page 8: ...ceplate assembly item 4 To remove the faceplate assembly do the following 1 At the same time push the two 2 catches located in the faceplate out of the way 2 Rotate the faceplate assembly approximately 10 counterclockwise 3 Carefully pull the faceplate assembly away from the housing item 6 or 7 i Notice Do not pull more than 12mm away from housing at this time 4 Using a soldering iron carefully di...

Page 9: ...ee 3 boom wires from the circuit board boom side only 6 Remove the circuit board i Notice The board is still attached to the overhead wires dual side versions only 3 1 5 Removing the circuit board item 9 or 10 Follow the steps in Remove boom assembly cover item 13 page 9 4 Disconnect the four overhead wires dual side versions only 3 1 6 Removing the housing item 6 or 7 or temple plate assembly ite...

Page 10: ... be done exactly the reverse order of the disassembly procedure to ensure proper headset fit and operation Please take care to properly align parts and wires to ensure proper operation See disassembly procedure parts lists assembly diagrams and wiring diagrams for reference 17 1 2 3 3 4 4 6 8 7 8 9 10 11 11 12 13 14 5 18 21 22 23 24 25 26 25 22 23 26 Figure 3 1 Airman 850 headset dual sided explod...

Page 11: ...sassembly Assembly en 11 Bosch Security Systems LLC Customer maintenance manual 09 2021 V07 F 01U 264 819 17 1 3 2 4 5 6 8 9 11 13 14 15 16 18 24 25 26 22 23 Figure 3 2 Airman 850 headset single sided exploded view ...

Page 12: ... 09 2021 V07 F 01U 264 819 Customer maintenance manual Bosch Security Systems LLC R o t a t e Assemble Remove Catch Push from other side of faceplate Catch Push from other side of faceplate 10 Figure 3 3 Faceplate disassembly assembly view ...

Page 13: ...eadband assembly 1 No longer available Headband assembly 1 S F01U329357 F01U329357 Headband assembly 1 S 64318118 F01U216802 Headband assembly 1 2 800801000 F01U153681 Glider assembly 2 2 2 2 2 2 2 2 3 591486000 F01U151390 Cushion ear round 1 piece 2 2 2 2 1 1 1 2 800456020 F01U118432 Ear cushion 2 per package 1 1 1 1 1 1 1 1 4 800939000 F01U153698 Faceplate speaker assembly 2 2 2 2 1 1 1 1 5 7041...

Page 14: ...51 Windscreen 2 pcs for Airman 850 7 8 8 1 1 1 1 1 1 1 1 AIRMAN7 9050 F01U393945 50 pc windscreen bulk Airman 850 7 8 8 1 1 1 1 1 1 1 1 AIRMAN7 9100 F01U393946 100 pc windscreen bulk Airman 850 7 8 8 1 1 1 1 1 1 1 1 15 70531101 F01U152640 Temple pad not printed 1 1 1 16 70533000 F01U110213 Foam pad 1 1 1 17 590637000 F01U157438 Clothing clip 1 1 1 1 1 1 1 1 18 64305000 F01U110016 Glider spring 1 p...

Page 15: ...ot shown 4 This item is part of the headband assembly no 1 or can be purchased separately 5 This item is part of Boom assembly no 13 or can be purchased separately 6 Acoustic cloth is now included as part of no 3 Only one acoustic cloth can be used at a time either the spare part that needs to be attached to the faceplate no 4 or the cloth that is included in the replacement ear cushion 7 The ANR ...

Page 16: ...r maintenance manual Bosch Security Systems LLC 5 Wiring diagrams 5 1 Airman 850 wiring diagram catalog numbers 301317 000 002 003 101 and 400 Figure 5 1 Top side Airman 850 dual sided wiring diagram Figure 5 2 Bottom side Airman 850 headset dual sided wiring diagram ...

Page 17: ...iagrams en 17 Bosch Security Systems LLC Customer maintenance manual 09 2021 V07 F 01U 264 819 5 2 Airman 850 wiring diagram catalog numbers 301317 200 201 and 300 Figure 5 3 Airman 850 headset single sided wiring diagram ...

Page 18: ...adset connector view molded plugs 5 3 2 Connector view for catalog numbers 301317 101 and 201 Figure 5 5 Airman 850 headset connector view mechanical plugs 5 3 3 Connector view for catalog number 301317 002 Figure 5 6 Airman 850 headset connector view XLR plug 5 3 4 Connector wiring diagram for catalog numbers 301317 000 003 101 200 201 300 and 400 PJ 068 or equivalent PJ 055 or equivalent Figure ...

Page 19: ...LLC Customer maintenance manual 09 2021 V07 F 01U 264 819 5 3 5 Connector wiring diagram for catalog number 301317 002 5 pin XLR 4 3 1 2 5 Pin 5 N C Pin 4 Black shield Pin 3 Red Pin 2 Yellow Pin 1 White Figure 5 8 Airman 850 headset 5 pin XLR wiring diagram ...

Page 20: ... 1 2W 5 25 Vdc V OUT CONNECT TO MICROPHONE PLUG 25 Figure 6 1 Airman 850 headset boom microphone sensitivity check and adjustment test circuit 3 Calibrate a lab microphone either self contained such as Larson Davis sound level meter or a separate measuring microphone with supporting equipment such as Bruel and Kjaer type 4192 with type 2669 B preamp 4 Place the calibrated lab microphone 1 4 inch 6...

Page 21: ...urn the gain adjustment control in the microphone housing using a small screwdriver For more information see the illustration below Clockwise adjustment increases output level Gain Adjustment Figure 6 2 Airman 850 headset boom microphone gain adjustment location 6 1 3 Troubleshooting mic failure The microphone circuitry is in two 2 parts the boom microphone preamp and main amp located on the main ...

Page 22: ...s shown in the previous illustration This test is not designed for absolute accuracy but rather to tell if the boom assembly is functioning properly If no output or no acceptable output is obtainable then replace the boom assembly Testing the Circuit board assembly To test the circuit board assembly do the following 1 Construct a test circuit For more information see illustration below 2 Connect t...

Page 23: ...gainst that of the Reference microphone perceived in the previous step For comparison purpose it might be necessary to talk into the Reference microphone again after reinserting its plug into the intercom jack on the Copilot side 4 If the DUT microphone yields comparable loudness and clarity to that of the Reference microphone remove the plugs of the Reference headset from the intercom 5 Wear the ...

Page 24: ...n low volume setting 3 Measure and record the acoustic output over the frequency range of 350 Hz to 3 KHz The resultant curve should fit the limits as defined in Receiver frequency response table in Specifications page 29 4 Repeat steps 1 through 4 with the second speaker if applicable 5 Measure current of 12V Power Supply The current should be 4 mA 1 mA with 1 mW applied to the speaker and ANR tu...

Page 25: ...d equipment The Airman 850 ANR test and adjustment procedure requires the following acoustic test equipment and custom fixture Audio Test System Audio Precision or equivalent test system or Artificial Mouth Bruel Kjaer 4227 or equivalent speaker Artificial Ear with 6cc Coupler Bruel Kjaer 4153 Supporting hardware for Microphone Supporting hardware and software for audio test system Custom ANR test...

Page 26: ...uency sweep and save the file With ANR turned on perform a frequency sweep and save the file 5 Subtract the two sweep results files measured in the previous step The resulting curve should fit within the limits as shown in Minimum attenuation requirements linearize between points page 25 i Notice The following is an alternative way of testing ANR 1 Wear the DUT headset with the ANR switch set to O...

Page 27: ... time The cleaner should wipe off or evaporate quickly Do not allow alcohol or any liquid to touch the speaker or microphone element Use only isopropyl alcohol 70 minimum on foam windscreen Once removed soak the windscreen or spray onto the foam until it is completely saturated Squeeze out excess liquid and allow to air dry at room temperature before reattaching Cleaning directions here are consid...

Page 28: ...eck boom mic assembly Check circuit boards Receiver inoperative X X X X X Microphone inoperative X X X X X Receiver intermittent X X X X Microphone intermittent X X X X Distorted receiver signal X X X Distorted microphone signal X X X Receiver level varies between left and right sides1 X X X Receiver level does not meet specifications for power on and power off X Microphone level cannot be adjuste...

Page 29: ...ing impedance 150 Ohms Frequency response 100 10000 Hz RTCA DO 214 curve Sensitivity 48 3 dB ref 1 V ubar 1 kHz 12 VDC 470 Ohm DC 150 Ohm AC load Operating voltage 8 28 Vdc 470 Ohm load Active noise reduction All models with active noise reduction utilize the microphone system for power Plug type Varies by model refer to parts list Approximate wearing weight 2 9 oz single sided without cord 3 8 oz...

Page 30: ...ance 301317 000 Airman 850 Headset Dual sided 150 Ohms 301317 002 Airman 850 Headset Dual sided 600 Ohms 301317 003 Airman 850 Headset Dual sided 600 Ohms 301317 101 Airman 850 Headset Dual sided customer specific 150 Ohms 301317 200 Airman 850 Headset Single sided 150 Ohms 301317 201 Airman 850 Headset Single sided customer specific 150 Ohms 301317 300 Airman 850 Headset Single sided 300 Ohms 301...

Page 31: ...Airman 850 Appendices en 31 Bosch Security Systems LLC Customer maintenance manual 09 2021 V07 F 01U 264 819 9 Appendices Figure 9 1 ANR test fixture drawing ...

Page 32: ...32 Appendices Airman 850 09 2021 V07 F 01U 264 819 Customer maintenance manual Bosch Security Systems LLC ...

Page 33: ......

Page 34: ...TELEX 12000 Portland Avenue South Burnsville MN 55337 USA www telex com Bosch Security Systems LLC 2021 202109282043 ...

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