Technisonic Industries Limited TFM-138, Инструкция по установке и эксплуатации

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APPENDIX TO “INSTALLATION INSTRUCTIONS”
POST INSTALLATION EMI TEST
PURPOSE
The purpose of this test is to identify any interference that the TFM-138, TFM-138A or TFM-138B
may cause with existing aircraft systems. For simplicity all TFM-138 model variations will be
referred as TFM-138 series transceivers in this document.
TEST CONDITIONS
The TFM-138 series transceiver should be installed and function tested. The antenna VSWR should
be checked. A forward/reverse power check with a in-line wattmeter should show no more than
10% reflected power. For the following tests, insure that the power switch is in the high position.
METHODOLOGY
Most of the EMI tests can be accomplished on the ground. In some cases flight testing is required
or is easier. If the aircraft is approved for IFR operations, then it is mandatory that interference
between the TFM-138 Airborne FM and the approach aids be checked in flight.
The GPS should be operational and navigating with at least the minimum compliment of satellites.
The VHF comm should be set to the frequencies indicated with the squelch open. VOR/ILS/GS
receivers should be set to the frequencies indicated and selected for display If possible, set up a
VOR/ILS ramp test set on the frequencies indicated and adjust the output until the flags are out of
view. The transponder and encoder should be monitored with ramp test equipment. If possible set
the ADF to a nearby navigation station.
Modulate the TFM-138 transmitter on the indicated frequencies for at least 20 seconds.
Observe the GPS for any degradation in satellite status or availability or flags. Listen for any noise
or detected audio signals on the VHF comm(s). Listen for any noise or detected audio signals on the
VOR/LOC receiver audio; look for any moment of flags or needles on the VOR/LOC/GS navigation
display(s).
List the power plant, fuel and other electric instruments in the chart provided and note any
anomalies that occur while transmitting. Assess the results.
If the aircraft is equipped with an autopilot or a stability augmentation system, then test fly the
aircraft and verify that operation of the TFM-138 transceiver does not have adverse effects on these
systems. After checking for gross effects at a safe altitude, fly an approach with each of the
different navigation systems coupled to the autopilot (ILS, GPS ETC.) and look for any anomalies.
RESULTS
If the installed system passes all of the applicable EMI tests, then no further action is required. If
interference is observed then the interference must be assessed against the appropriate standards of
airworthiness for the system in question. For example it is permissible for a VFR certified GPS to
lose navigation capability while the TFM-138 unit is transmitting, providing that it recovers properly
and promptly, but it is not permissible for an IFR Approach certified GPS to affected in the same
way. A complete discussion of all the standards of airworthiness to be applied in assessing EMI
effects is beyond the scope of this document.