TECHNISONIC INDUSTRIES LIMITED
www.til.ca
TDFM-7000 Installation & Operating Instructions
TiL 05RE375 Rev n/c Issue 13
3-12
D.
The following procedure checks for second harmonic interference to the glide slope receiver
from the TDFM-7000. All transceivers produce harmonics (multiples of the wanted
frequency) and while the TDFM-7000 far exceeds FCC requirements, interference can still
be experienced depending upon antenna position and separation. Furthermore, harmonics
can be generated by other equipment in the aircraft and the structure of the aircraft where
dissimilar metals make contact or where grounds are isolated, etc. This is also true of
aircraft hangars, therefore testing should be done outside away from any structures where
possible.
With a portable glide slope generator, provide enough signal to firmly activate the indicator
needle and hide all flags. Increase the signal level by 3 dB. Modulate the TDFM-7000
transmitter on the following frequencies for at least 20 seconds. Observe the Glide Slope
displays. Look for any movement of flags or needles on the navigation display. If an
interference condition is detected, then the installation will have to be flight tested
according to the following procedure. Using the table below, determine the glide slope
frequency based on the localizer frequency of the ILS to be used. Divide the glide slope
frequency by 2 and program into the TDFM-7000. Fly the aircraft to intercept the localizer
and glide slope (both needles centered) at 26 nm from the runway. Transmit on the TDFM-
7000 for 10 seconds and watch for any deflections or flags. Repeat the test every 2 nm
until the indicators are not affected. If the distance is greater than 18 nm then a pass shall
be recorded. Otherwise the TDFM-7000 shall be placarded “Do not transmit while on ILS
approach”.
Localizer Glide
slope
Localizer Glide
slope
108.10
334.70
110.10
334.40
108.15
334.55
110.15
334.25
108.30
334.10
110.30
335.00
108.35
333.95
110.35
334.85
108.50
329.90
110.50
329.60
108.55
329.75
110.55
329.45
108.70
330.50
110.70
330.20
108.75
330.35
110.75
330.05
108.90
329.30
110.90
330.80
108.95
329.15
110.95
330.65
109.10
331.40
111.10
331.70
109.15
331.25
111.15
331.55
109.30
332.00
111.30
332.30
109.35
331.85
111.35
332.15
109.50
332.60
111.50
332.90
109.55
332.35
111.55
332.75
109.70
333.20
111.70
333.50
109.75
333.05
111.75
333.35
109.90
333.80
111.90
331.10
109.95
333.65
111.95
330.95
Summary of Contents for TDFM-7000
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