EFD1000 E5 Dual Electronic Flight Instrument (EFI) Install Manual
DOCUMENT # 900-00041-001
PAGE 114-226
REVISION D
© Copyright 2019 Aspen Avionics Inc.
NARCO and Cessna ARC Radio Interfaces
Figure 9-15A: Narco and Cessna ARC Navigation Radios
ACU/ACU2
1
NAV Composite
20
2
32
13
31
12
Composite GND
/ILS Engage
GS +UP
GS +DN
GS -FLG
GS +FLG
1
P2
2
Capacitor is electrolytic type from 10uf to 47uf with
a minimum 25V rating. Paralleling of composite
signal to backup NAV indicator is made between
capacitor and NAV radio.
3
Diode required when paralleling ILS Energize wire
with backup NAV indicator. Use IN4005.
+
2
Narco or
Cessna ARC
1
NAV Composite Out
/ILS Engage
GS +UP
GS +DN
GS +FLAG
GS -FLAG
Refer to manufacturers’ documentation to verify the
integration data and for information regarding
checkout procedures. This drawing, as it pertains to
the non-Aspen equipment, is for reference only.
4
3
Includes other manufacturers Narco and ARC
replacement radios
Composite Phase (VOR1,2) = 180
Note:
The composite output from these radios use a DC offset voltage. A capacitor is required as shown below.
Note:
The Glide Slope output from some Narco radios can only drive one load and therefore it may not be
possible to parallel these to a mechanical NAV indicator as well as the ACU. This also may apply to radios
with integrated CDI/VDI (i.e., NAV 122) as they were not designed to drive an external load. ACU2
installations can use the high impedance MK12D GS Flag input which may allow paralleling the indicator.
Note:
If it is not possible to connect the Glide Slope output to the ACU the composite and ILS Energize can still
be connected so that it can be used as a CDI on the HSI and as a bearing pointer.
Note:
The composite output with some of these radios is 180
degrees out of phase so the “Composite Phase
(VOR1,2)
” must be configured for 180 in the EFD1000 configuration.
54
53
MK12D GS -FLG
MK12D GS +FLG
P4
(ACU2 only)
or
4
Do Not connect GS Flag to both P2 and P4
connectors. Use only one input. For ACU2
installations it is recommended to use the P4 input on
all Narco radios.
5
