REVISION HISTORY
REV DCA
H
DATE
Refer to the DCA and associated markups for a complete description of
the changes incorporated in a revision.
DRAWN
W12987 03/06/2013 Ken Marshall
CHECKED
APPROVED
PUBLISHED
Heath Flor
Dan Brasher
Linda Andujo
Published on
3/13/2013
IMPORTANT NOTICE
Chelton Avionics Inc. doing business as Wulfsburg
Electronics Division is responsible for full distribution and
revisions of ICA’s (Instructions for Continued Airworthiness).
For inquiries regarding the content and currency of this
manual contact Wulfsberg Electronics Division, 6400
Wilkinson Drive, Prescott, Arizona, 86301. Telephone: (928)
756-1615 or refer to the following website:
www.wulfsberg.com for more information.
THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION.
NEITHER RECEIPT NOR POSSESSION OF THIS DOCUMENT CONFERS ANY RIGHT TO REPRODUCE, USE OR DISCLOSE, IN WHOLE OR IN PART, ANY
INFORMATION CONTAINED IN THIS DOCUMENT WITHOUT WRITTEN AUTHORIZATION FROM WULFSBERG ELECTRONICS.
TEMPLATE 150-744545-01 REV. C
Chelton Avionics, Inc.
dba Wulfsberg Electronics Division
Prescott, AZ
CAGE
CODE
1B7G3
DOCUMENT TITLE
A PRINTED COPY OF THIS DOCUMENT MAY NOT BE THE
LATEST REVISION.
IT IS THE USER’S RESPONSIBILITY TO ENSURE THAT HE OR
SHE IS USING THE LATEST DOCUMENT REVISION.
THE LATEST REVISION MAY BE VIEWED OR PRINTED FROM THE
ELECTRONIC DOCUMENT DISTRIBUTION SYSTEM.
INSTALLATION MANUAL,
CVN-251 VHF NAVIGATION SYSTEM
SIZE
LRU
A CVN-251
Typed signatures indicate approval. Handwritten signature approval of
this document is on file at Wulfsberg Electronics, Prescott, Arizona.
SCALE: NONE
DOCUMENT NUMBER
REV
150-048500
H
DO NOT SCALE DRAWING
Page 1
FliteLine CVN-251
VHF Navigation System
Installation Manual
Installation
Manual
Engineering and Production of FliteLine™ Components by
Wulfsberg Electronics,
A Cobham Avionics & Surveillance Group Company
Wulfsberg Electronics
CVN-251
VHF Navigation System
Manual Number 150-048500
Revision H
150-048500 Rev. H
Page 2
FliteLine CVN-251
VHF Navigation System
Installation Manual
Wulfsberg Electronics, A Cobham Avionics & Surveillance Group Company located in Prescott, Arizona, designs
and manufactures the Wulfsberg Electronics FliteLine™ line of products, including the CVN-251 VHF Navigation
System. For more than 25 years, Wulfsberg Electronics has distinguished itself by providing top quality avionics
products for civil, air transport, and military applications.
Wulfsberg Electronics makes no warranty, expressed or implied, with regard to this manual, including but not
limited to any implied warranties of merchantability, fitness for a particular purpose, and non-infringement. In
addition, Wulfsberg Electronics makes no warranty with regard to the documentation or data contained herein.
Wulfsberg Electronics is not liable in the event of incidental, special, consequential, or any other damages in
connection with or arising from furnishing, performance, or use of this manual.
Changes or modifications not expressly approved by the party responsible for compliance could void the user’s
authority to operate the equipment.
Reproduction of this publication or any portion thereof by any means is prohibited. For further information contact
Sales, Wulfsberg Electronics, 6400 Wilkinson Drive, Prescott, Arizona, 86301. Telephone: (928) 708-1500.
Information in this manual is subject to change without notice.
 2004 Wulfsberg Electronics. All rights reserved
CVN-251 are trademarks of Wulfsberg Electronics.
PROPRIETARY NOTICE
This document contains proprietary information and such information may not be disclosed to others for any
purpose, nor used for manufacturing purposes without written permission from Wulfsberg Electronics.
150-048500 Rev. H
Page 3
FliteLine CVN-251
VHF Navigation System
Installation Manual
Record of Revisions
Rev
No.
Rev
Date
A
12/15/2005
B
09/08/2006
C
12/11/2006
D
03/29/2007
E
08/31/2007
F
09/19/2008
G
09/21/2009
H
03/13/2013
150-048500 Rev. H
Date
Inserted
By
Rev
No.
Rev
Date
Date
Inserted
By
Page 4
FliteLine CVN-251
VHF Navigation System
Installation Manual
Table of Contents
Section
Page
SECTION 1 – GENERAL INFORMATION
1.
Introduction ....................................................................................................................................................... 8
2.
Applicability ........................................................................................................................................................ 8
3.
Equipment Description ...................................................................................................................................... 8
A.
CVN-251 VHF Navigation Receiver/ Processor ....................................................................................... 8
B.
CVN-252 FliteLine Control Display .......................................................................................................... 8
4.
Available Configuration Variations ..................................................................................................................... 9
5.
Technical Specifications ................................................................................................................................. 10
A.
ARINC 429 Information .......................................................................................................................... 10
B.
Unit Information ....................................................................................................................................... 11
6.
Installation Kits and Accessories .................................................................................................................... 14
A. CVN-251 Connector Kits ......................................................................................................................... 14
B. Single Mounting ...................................................................................................................................... 14
C. Dual Mounting .......................................................................................................................................... 14
D. Retrofit Installations ................................................................................................................................. 14
7.
Accessories Required But Not Supplied .......................................................................................................... 14
8.
Recommended Antennas ................................................................................................................................ 15
9.
Tools Required But Not Supplied .................................................................................................................... 15
10. License Requirements ..................................................................................................................................... 15
11. Instruction for Continued Airworthiness ........................................................................................................... 15
12. Certification Considerations ............................................................................................................................. 15
13. FCC Compliance.............................................................................................................................................. 16
14. ESDS Device Labels and Symbols ................................................................................................................. 16
SECTION 2 – INSTALLATION
1.
General ............................................................................................................................................................ 17
2
Unpacking and Inspecting Equipment ............................................................................................................ 17
3
Equipment Installation .................................................................................................................................... 17
A. Cooling Considerations .......................................................................................................................... 17
B. CVN-251 Mechanical Installation ........................................................................................................... 17
Single Mounting Tray Installation Drawing, 154-048500 (Figure 2-1, Sheet 1) ..................................... 18
4” Mounting Tray Installation Drawing, 154-048500 (Figure 2-1, Sheet 2) ............................................ 19
Dual Mounting Tray Installation Drawing, 154-048500 (Figure 2-1, Sheet 3) ........................................ 20
Interconnect Wiring Diagram (CVN-251 to CVN-252) 152-248530 (Figure 2-2) .................................... 21
Interconnect Wiring Diagram (CVN-251 to CVN-252) 152-248150 (Figure 2-3) ................................... 22
150-048500 Rev. H
Page 5
FliteLine CVN-251
VHF Navigation System
Installation Manual
Table of Contents
Section
Page
SECTION 2 – INSTALLATION (cont’d)
C. CVN-251 Harness and Connector Assembly ......................................................................................... 23
D. Antenna Installation ................................................................................................................................ 28
E. Strapping Options ................................................................................................................................... 29
4
Post-Installation Checkout Procedure ............................................................................................................. 29
A. Visual Inspection...................................................................................................................................... 29
B. In-Aircraft Adjustments ........................................................................................................................... 29
C. Preflight Check ........................................................................................................................................ 30
5
Flight Test Procedure ...................................................................................................................................... 32
SECTION 3 – OPERATION
1.
General ........................................................................................................................................................... 33
150-048500 Rev. H
Page 6
FliteLine CVN-251
VHF Navigation System
Installation Manual
Table of Contents
LIST OF TABLES
Section
Page
1-1 CVN-251 Configuration Variations..................................................................................................................... 9
1-2 ARINC 429 Received Labels ........................................................................................................................... 10
1-3 ARINC 429 Transmitted Labels ....................................................................................................................... 10
1-4 ARINC 429 SDI Bits Definition ......................................................................................................................... 10
1-5 ARINC 429 Labels Update Rate (ARINC 429-7) ............................................................................................. 11
1-6 CVN-251 Specifications ................................................................................................................................... 11
1-7 CVN-251 Connector Kit Part List (050-02398-0000, Rev E) ........................................................................... 14
1-8 Recommended Antennas ................................................................................................................................ 15
1-9 Tools Required But Not Supplied .................................................................................................................... 15
2-1 CVN-251 Pin-outs ............................................................................................................................................ 25
LIST OF FIGURES
Section
1
Page
Electrostatic Discharge Sensitive Device Labels and Symbols ....................................................................... 16
2-1 CVN-251 Single Mounting Tray Installation (Sheet 1 of 3) ............................................................................. 18
2-1 CVN-251 4” Mounting Tray Installation Drawing (Sheet 2 of 3) ...................................................................... 19
2-1 CVN-251 Dual Mounting Tray Installation Drawing (Sheet 3 of 3) .................................................................. 20
2-2 Interconnect Wiring Diagram, CVN-251 to CVN-252 ...................................................................................... 21
2-3 Interconnect Wiring Diagram, CVC-151 and CVN-251 to CCN-995 ............................................................... 22
2-4 RF Cable Fabrication ....................................................................................................................................... 23
2-5 CVN-251 Rack Mount Connector .................................................................................................................... 24
2-6 CVN-251 Polarizing Post Assembly ................................................................................................................ 27
150-048500 Rev. H
Page 7
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 1 – General Information
SECTION 1 – GENERAL INFORMATION
1.
Introduction
This section contains information relative to the physical, mechanical, and electrical characteristics of the Wulfsberg
Electronics CVN-251 VHF Navigation System.
2.
Applicability
This manual is applicable to all CVN-251 FliteLine VHF Navigation Receivers built at the Prescott, Arizona facility.
3.
Equipment Description
The Wulfsberg CVN-251 Navigation Receiver is a remote mounted radio intended to be used with a cockpit
mounted display such as the CVN-252 or CD-412 NAV Control Displays or and ARINC 429 bus compatible Radio
Management Unit, (RMU). Left/right and up/down deviation information is available in either analog or ARINC 429
bus outputs. These outputs are suitable for application to a variety of analog, mechanical, or electronic displays
and can be applied to an Automatic Flight Control Systems (AFCS).
The CVN-251 is lightweight Digital Signal Processor (DSP) based VHF navigation receiver system, which will
receive VHF Omni Range (VOR), Localizer, and Glideslope stations and supply course error information. The
Marker Beacon receiver will provide annunciation from Marker Beacon transmitters.
In the VOR mode, the CVN-251 measures the radial of the received VOR station and produces the appropriate
To/From indication and Course Deviation in relation to the OBS setting. In the ILS mode, it outputs left/right and
up/down displacement for the Localizer and Glideslope center lines.
A. CVN-251 VHF Navigation Receiver/Processor
The CVN-251 converts VOR/LOC and Glideslope signals to standard course error indications as well as provides
composite output signals for external equipment. It is compatible with the most electromechanical HIS, CDI, and
RMI displays. ARINC 429 serial data provides interfacing with EFIS and Flight Management Systems.
The Marker Beacon receiver provides Outer, Middle, or Inner marker aural tones when received for the Marker
base station. The Marker Beacon receiver has lamp outputs used to drive external
maker beacon lamps.
The NAV receiver provides voice audio demodulation from the VOR or Localizer ground station. This provides
means for identification of the base station’s Morse code identification signal.
B. CVN-252 Control Display Unit
The CVN-252 Control Display Unit is designed to be mounted in the instrument panel individually,
or combined in pairs in an adapter plate that will fit a standard DZUS mounting.
The control display establishes and displays the operating status of all the CVN-251 functions.
Nonvolatile memory in the CVN-251 is used to retain the last frequency used, thus eliminating
frequency changes as a result of momentary of extended power disruptions.
The CVN-251 uses full-time self-test to monitor key internal circuits and will display the word “FAIL”
followed by a pre-assigned number to indicate to failure on the CVN-251 display.
The CVN-252 provides active/standby display of frequency with “flip-flop” transfer ability between the
Active and Standby Frequency. Selectable Bearing or Radial information is also displayed as well as a
referenced for Nav 1 or Nav 2 radio system indication.
150-048500 Rev. H
Page 8
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 1 – General Information
4.
Available Configuration Variations
The following tables list the currently available configuration variations of the CVN-251.
Table 1-1 CVN-251 Configuration Variations (Rev. K)
150-048500 Rev. H
Page 9
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 1 – General Information
5.
Technical Specifications
A.
ARINC 429 INFORMATION
Table 1-2. ARINC 429 Received Labels
LABEL
INFO CONTAINED IN LABEL
UNITS
FORMAT
SPEED
033
ILS FREQUENCY
MHz
BCD
LOW
034
VOR ILS FREQUENCY
MHz
BCD
LOW
Note: Label 033 is only received or transmitted when the Label 033 enable pin is held low.
Table 1-3. ARINC 429 Transmitted Labels
LABEL
INFO CONTAINED IN LABEL
UNITS
FORMAT
SPEED
034
VOR ILS FREQUENCY
MHz
BCD
LOW
035
DME FREQUENCY
MHz
BCD
LOW
033
ILS FREQUENCY
MHz
BCD
LOW
100
SELECTED COURSE
DEG/180
BNR
LOW
173
LEFT RIGHT DEVIATION
DDM
BNR
LOW
174
UP DOWN DEVIATION
DDM
BNR
LOW
222
VOR BEARING
DEG/180
BNR
LOW
371
COMPANY INFORMATION LABEL
DSC
Application
Dependent
LOW
If the receiver is in a mode of operation where the above label is invalid, the label will have the Sign
Status matrix bits set for “no computed data”.
Table 1-4. ARINC 429 SDI bits definition
SDI Bits
P1001
P1001
Radio Number
10 9
Pin 15
Pin 44
0 0
Gnd
Gnd
All Call
0 1
Gnd
Open
NAV 1
1 0
Open
Gnd
NAV 2
1 1
Open
Open
NAV 3
All radios will listen to ARINC labels with All Call SDI bits.
150-048500 Rev. H
Page 10
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 1 – General Information
Table 1-5. ARINC 429 Labels Update Rate (ARINC 429-7, Attachment 2)
ARINC Label
Transmit Interval Min. mSec
Transmit Interval Max. mSec
34
167
333
35
100
200
100
167
333
173
33.3
66.6
174
33.3
66.6
222
50
100
371
500
1000
B. UNIT INFORMATION
Table 1-6. CVN-251 Specifications
CERTIFICATION:
NAV Receiver (VOR)
TSO-C40c, DO-196 and EUROCAE ED-22B
NAV Receiver (LOC)
TSO-C36e, DO-195 Class B and EUROCAE ED-46B
Glideslope Receiver
TSO C34e, DO-192 and EUROCAE ED-47B
Marker Receiver
TSO C35d, DO-143 Cat A and EUROCAE 1/WG 7/70
Environmental Category
DO-160E and EUROCAE ED-14E
[(F2)Z]AAB[S(M)R(B)(B1)U(G)]EWXXXXZZAZCC[FY]H[A3E33]XXAX
FCC IDENTIFICATION:
FRWCVN-251
TEMPERATURE RANGE:
Operational
-55 C to +70 C (-67 F to +158 F)
Storage
-55 C to +85 C (-67 F to +185 F)
COOLING:
Free air circulation
ALTITUDE:
55,000 feet (16,764 meters)
WEIGHT (Standard Configuration) *:
CVN-251
3.92 lbs. Maximum (1.78 kg)
Single mounting tray
0.97 lbs. Maximum (0.44 kg)
Dual mounting tray
2.48 lbs. Maximum (1.25 kg)
OVERALL DIMENSIONS (Standard Configuration) *:
Height:
4.00 inches maximum (101.60 mm)
Width:
2.40 inches maximum (60.96 mm)
Length:
13.30 inches maximum (337.82 mm)
*Note: See Figure 2-1 for weights and dimensions of CVN-251 in mounting tray and with available options.
INPUT POWER:
150-048500 Rev. H
850 mA Nominal, 1.25 amps max. at 27.5 ±0.2 VDC, 18 to 33 Vdc input.
Page 11
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 1 – General Information
TABLE 1-6. CVN-251 SPECIFICATIONS (cont’d)
Navigation Receiver
ANTENNA IMPEDANCE:
50 ohms
FREQUENCY CONTROL:
Gray Code or ARINC 429
FREQUENCY RANGE:
108.00 – 117.95 MHz
FREQUENCY MEMORY:
Nonvolatile
CHANNEL SPACING:
50 kHz
VOR CHANNELS:
160
LOC CHANNELS:
40
RECEIVER SENSITIVITY:
-100 dBm for 6 dB + S/N Ratio (Aural Reception)
RECEIVER SELECTIVITY:
6 dB maximum @  17 kHz
60 dB minimum @  36 kHz
FLAG SENSITIVITY:
-106 dBm maximum for non-flag operations
AGC:
Audio output will not vary more than 3 dB with inputs from
-93 dBm to -27 dBm
AUDIO FREQUENCY:
3 dB maximum variation from 350 Hz to 2,500 Hz response
AUDIO DISTORTION:
15% maximum with input levels from -93 dBm to -27 dBm signal
modulated 30% @ 1000 Hz
AUDIO OUTPUT:
10 mW into 600 Ohms
20 mW into 600 Ohms
40 mW into 600 Ohms
VOR COMPOSITE SIGNAL:
0.5 ± 10% Vrms into 10 k ohms when RF signal is 30% amplitude
modulated
(Determined by part number as
listed in Table 1-1)
NAV Converter
VOR DEVIATION SENSITIVITY:
150 mV for 10 off course, capable of three 1,000 ohm loads
LOC DEVIATION SENSITIVITY:
90 mV for 0.093 DDM, capable of three 1,000 ohm loads
VOR ACCURACY:
 1
LOC ACCURACY:
 5.0 mV
LOW LEVEL FLAG CIRCUITS:
Capable of driving three 1,000 ohm, 250 A meter movements
connected in parallel
HIGH LEVEL FLAG CIRCUITS:
18 V min. @ 250 mA
TO/FROM LOADS:
Drives three 200 ohms, 200 A meter movements
VOR RMI OUTPUT:
Sine/cosine (2-wire sine, 2-wire cosine), 400 Hz square wave (7.9 V
zero to peak)
OBS:
Course resolver electrical zero at 300 with 400 Hz
RMI ACCURACY:
 1.5 (Bench),  2.7 (Environmental)
Continues…….
150-048500 Rev. H
Page 12
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 1 – General Information
TABLE 1-6. CVN-251 SPECIFICATIONS (cont’d)
Glideslope Receiver
ANTENNA IMPEDANCE:
50 ohms
FREQUENCY RANGE:
329.15 – 335.00 MHz
CHANNEL SPACING:
150 kHz
NUMBER OF CHANNELS:
40
RECEIVER SENSITIVITY:
-87 dBm or less for non-flagged operations
SELECTIVITY:
6 dB maximum @  17 kHz 60 dB minimum @ 133 kHz
NOISE LEVEL:
30 dB minimum (S+N)/N ratio for -73 dBm input
SPURIOUS REJECTION:
Better than 60 dB
DEFLECTION AGC:
Within 10% of standard deflection with input signal variation of -73
dBm to -33 dBm
GLIDESLOPE COMPOSITE:
0.35 Vrms into 10 k ohms at 40% AM modulation
Glideslope Converter
CENTERING ACCURACY:
 5 mV
DEVIATION SENSITIVITY:
78 mV for 0.091 DDM capable of driving 333 Ohm loads
FLAG OUTPUT:
Capable of 333 Ohms at 750 A meter
SUPER FLAG:
18 V minimum @ 250 mA
Marker Receiver
ANTENNA IMPEDANCE:
50 ohms
OPERATING FREQUENCY:
75.00 MHz
THRESHOLD ADJUSTMENT
RANGE:
-70 dBm to -40 dBm
THRESHOLD ADJUSTMENT
SETTINGS
-66 dBm, (HIGH SENSITIVITY):
AUDIO FREQUENCY
RESPONSE
Audio output variation less than 6 dB from 350 to 3,000 Hz
AUDIO FREQUENCY
DISTORTION
5% maximum at rated output (95% modulation at -33 dBm)
LAMP FREQUENCY
RESPONSE:
RF input level variation required to produce (lamp) threshold is 6 dB or
less when 400 Hz, 1300 Hz and 3000 Hz modulating frequencies are
varied  5%
SELECTIVITY:
40 dB minimum @ 200 kHz
AUDIO OUTPUT:
10 mW into 600 ohms,
20 mW into 600 ohms, or
40 mW into 600 ohms depending on Model number
150-048500 Rev. H
-53 dBm, SETTING (LOW SENSITIVITY):
Page 13
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 1 – General Information
6.
Installation Kits and Accessories
A. CVN-251 Connector Kit
Installation of a CVN-251 requires a connector kit, P/N 050-02398-0000. The contents of the kit are as
follows:
Table 1-7. Part list, CVN-251 Connector Kit (050-02398-0000, Rev. E)
PART NUMBER
DESCRIPTION
U/M
QTY
030-02704-0000
Connector DPXBMA-A106-33P-03F0
EA
1
030-01311-0000
CONTACT, PIN, CRIMP
EA
106
089-06008-0005
SCR FHP 4-40X5/16
EA
4
156-041929-01
LABLE, MOUNTING TRAY CONNECTOR KIT,
VC-401B, VC-401C, DM-441B, CDM-451
EA
1
B. Single Mounting
When installing a single system, use P/N 400-048124-01 (Single Mounting Tray, Non-Safety Wire
Compatible, 2.5 inch), P/N 071-04047-0000 (Single Mounting Tray, Safety Wire Compatible, 4
inch), or
P/N 071-04047-0002 (Mounting Tray, Non-Safety Wire Compatible, 4 inch) and one
connector kit
(050-02398-0000).
C. Dual Mounting
The CVN-251 racks are designed for stacking two units when required, as shown in
Figure 2-1 Sheet 3. Installing a dual mounted configuration requires P/N 400-048124-02 (Dual Mounting
Tray, Non-Safety Wire Compatible, 2.5 inch), P/N 071-04047-0001 (Dual Mounting Tray, Safety Wire
Compatible 4 inch), P/N 071-04047-0003 (Dual Mounting Tray,Non-Safety Wire Compatible 4 inch), with
two connector kits (050-02398-0000).
D. Retrofit Installations
The CVN-251 is designed to be installed in the VN-411B, 4” mounting rack, P/N 071-04047-0000, without
any aircraft changes. This allows for retrofit into existing installations with minimum effort. To mount the
CVN-251 into this rack the CVN-251 must be ordered with an adapter kit installed.
An adapter bracket is available to allow mounting of the CVN-251 into the wider Series III rack. This can
be ordered pre-installed on the unit or as an adapter kit, P/N 149-448014-01.
Note: Retrofit mounting will require a weight and balance change to the aircraft. To eliminate weight and
balance issues, the radio may be ordered with ballast installed.
7.
Accessories Required But Not Supplied
The CVN-251 requires an EFIS or a left/right, up/down indicator, RMI, and marker beacon lamps to display
navigation information.
An aircraft audio system, including headphones and/or speaker amplifier and speaker is required to process NAV
and Marker audio outputs.
A Glideslope, VOR/LOC, and Marker antenna are required.
150-048500 Rev. H
Page 14
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 1 – General Information
8.
Recommended Antennas
The following Wulfsberg antennas are recommended for a typical installation. The installer is responsible for
determining the suitability of these antennas on a specific installation.
Table 1-8 Recommended NAV Antennas
Marker Antenna
Part Number
Maximum Airspeed
CI 102
400 knots
CI 118
400 knots
CI 205-3
300 knots
CI 120-400
300 knots
CI 120G/S
600 knots
Cl 135-100
600 knots (non-scalloping)
VOR/LOC and GS Antenna
9.
Tools Required But Not Supplied
A special crimping tool, positioner and an insertion/extraction tool are needed when the CVN-251 is installed.
These tools and their part numbers (P/N) are listed below.
Table 1-9 Tools Required But Not Supplied
10.
CRIMPING TOOL
POSITIONER
INSERTION/EXTRACTION TOOL
MIL M22520/2-01
MIL M22520/2-23
AMP P/N 91066-1
License Requirements
Check in the country of operation with the governing body for any licensing requirements. The end user is
responsible for obtaining any required licenses.
This equipment has been type accepted by the FCC under type acceptance number FRWCVN-251.
11.
Instructions for Continued Airworthiness
There is no periodic maintenance required for this article. Maintenance and/or repair is only upon failure.
12.
Certification Considerations
The conditions and test for TSO approval of this article are minimum performance standards. It is the responsibility
of those desiring to install this article either on or within a specific type or class of aircraft to determine that the
aircraft installation conditions are within the TSO standards. The article may be installed only if further evaluation
by the applicant, i.e. user/installer, documents an acceptable installation and is approved by the administrator.
150-048500 Rev. H
Page 15
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 1 – General Information
13.
FCC Compliance
This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This
device may not cause harmful interference, and (2) this device must accept any interference received, including
interference that may cause undesired operation.
Part 15.21
Changes or modifications not expressly approved by the party responsible for compliance could void the user’s
authority to operate the equipment.
Note: The manufacturer is not responsible for any radio or TV interference caused by unauthorized modifications
to this equipment. Such modifications could void the user’s authority to operate the equipment.
14.
ESDS Device Labels and Symbols
Caution:
This equipment contains electrostatic discharge sensitive (ESDS) devices. All modules containing
ESDS devices are flagged or identified on schematics and assembly illustrations, and are individually
identified in the parts list. All ESDS devices must be handled in accordance with procedures outlined in
the "repair" section of this manual.
ESDS devices include, but are not limited to, C-MOS, J-MOS, PMOS, NMOS, SOCMOS, HMOS,
MOS/FET, microwave mixer diodes, some bipolar devices, and some metal film resistors.
The labels and symbols shown in Figure 1 are used by Wulfsberg to identify ESDS applications. The labels DO
NOT appear on units and modules manufactured prior to the adoption of the STANDARD symbol.
Identifies ESDS device is present and need for
special handling exists.
Figure 1. Electrostatic Discharge Sensitive (ESDS) Device Labels and Symbols
150-048500 Rev. H
Page 16
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
SECTION 2- INSTALLATION
1.
GENERAL
This section contains suggestions and factors to consider before installing the CVN-251. Close adherence to these
suggestions will assure the best performance from the equipment.
2.
UNPACKING AND INSPECTING EQUIPMENT
Use care when unpacking the equipment. Make a visual inspection of the units for evidence of damage incurred
during shipment. If a claim for damage is to be made, save the shipping container to substantiate the claim. The
claim should be promptly filed with the transportation company. It would be advisable to retain the container and
packaging material after all equipment has been removed in the event that equipment storage or reshipment should
become necessary.
3.
EQUIPMENT INSTALLATION
THE CVN-251 INSTALLATION WILL BE DETERMINED BY THE CUSTOMER’S REQUIREMENTS, THE INSTALLER,
AND SPACE AVAILABLE ON THE AIRCRAFT. BEFORE BEGINNING INSTALLATION, THE INSTALLER SHOULD
REVIEW THE DRAWINGS, ELECTRICAL INTERWIRING DIAGRAM, AND INSTALLATION PICTORIALS WHICH ARE
LOCATED IN THIS SECTION, AND ESTABLISH REQUIREMENTS TO A PARTICULAR AIRCRAFT. SEE FIGURE 2-1
FOR AN OUTLINE DRAWING OF THE EQUIPMENT.
A. Cooling Considerations
The greatest single contributor to increased reliability of all modern day avionics is lowering the operating
temperature of the individual units. While modern day circuit designs consume far less electrical energy, the
watts per cubic inch dissipated within the avionics units still remains much
the same due to the high density
packaging. Consequently, the importance of providing avionics cooling is essential to the life span of the unit.
While each individual unit may or may not require forced air cooling, the combined heat load of several
units operating in a typical avionics location will significantly degrade the reliability of the avionics if provisions for
cooling are not incorporated in the initial installation. Failure to provide cooling will certainly lead to increased
avionics maintenance costs and may void the Wulfsberg warranty.
B. CVN-251 Mechanical Installation
(1)
Select the CVN-251 mounting location. The location should be free from excessive moisture, vibration,
heat and electrical noise generating sources. The unit can be rigidly mounted. Allow at least one inch
of free air space around the top and rear of the unit and one-half inch along each side. Allow adequate
space for installation of cables and connectors.
(2)
Refer to Figure 2-1 for the CVN-251 mounting dimensions.
(3)
Mark, punch, and drill the mounting holes. Care must be taken to avoid damage to adjacent
equipment or cables.
(4)
Secure the mounting tray firmly in place.
(5)
Secure the CVN-251 to the mounting tray.
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
FIGURE 2-1. CVN-251 Single Mounting Tray Installation (SHEET 1 OF 3) (DWG. NO. 154-048500, REV C)
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
Figure 2-1. CVN-251 4” Mounting Tray Installation Drawing (Sheet 2 of 3) (Dwg. No. 154-048500, Rev C)
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
FIGURE 2-1.
CVN-251 Dual Mounting Tray Installation Drawing (SHEET 3 OF 3) (DWG. NO. 154-048500, REV C)
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
Figure 2-2.
Interconnect Wiring Diagram, CVN-251 to CVN-252 (Sheet 1 of 1) (Dwg. No. 152-248530, Rev E)
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
FIGURE 2-3.
Interconnect Wiring Diagram, CVC-151 AND CVN-251 TO CCN-995 (SHEET 1 OF 1) (DWG. NO. 152-248150, REV F)
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
C.
CVN-251 Harness and Connector Assembly
(1)
The installer will supply and fabricate all external cables. The connectors and hardware
required are supplied in the Wulfsberg installation kits listed in Section 1. Figure 2-3
illustrates the specific aspects of constructing the RF connector and the wiring connector
housing. Construction details for the antenna end of the coax cable are dependent on the
antenna selected by the installer.
Figure 2-4 RF Cable Fabrication
(2)
The length and routing of the external cables must be carefully studied and planned before
attempting actual installation. Avoid sharp bends and placing the cables too near the aircraft
control cables.
(3)
Use only recommended wire sizes and wire type for interconnect. Wire sizes and wire type
are listed on the interconnect diagrams.
(4)
Use Figures 2-3 and 2-4 to become familiar with the connectors and pin locations on the
plugs for the fabrication of the external cables.
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
Figure 2-5 CVN-251 Rack Mount Connector
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
Table 2-1 CVN-251 Pin-Outs
I/O
PIN
DESCRIPTION
I/O
PIN
DESCRIPTION
-
29
Reserved
I
1
-
2
NOT USED
I
30
GRAY CODE IN 2B
I
3
GRAY CODE IN 1B
-
31
Reserved
-
4
NOT USED
I
32
I
5
-
33
I
6
I
34
O
7
G/S_COMP
-
35
NOT USED
-
8
NOT USED
I
36
OBS STATOR F
I
9
OBS STATOR E
-
37
NOT USED
-
10
NOT USED
O
38
L/R DEV +RT
I
11
26 VAC_400HZ_C
O
39
RMI DC SINE
-
12
Reserved
O
40
RMI DC COS
I
13
-
41
Reserved
-
14
Reserved
-
42
NOT USED
I
15
SDI BIT 10
I
43
GRAY CODE IN 2A
-
16
Reserved
I
44
SDI BIT 9
O
17
D-CLOCK
B
45
SHIELD GND
-
18
Reserved
I
46
DC PWR GND
I
19
GRAY CODE IN 1A
B
47
ACFT GND
-
20
NOT USED
B
48
CHASSIS GND
O
21
NAV_COMP
I
49
OBS STATOR G
-
22
NOT USED
I
50
OBS STATOR D
O
23
UP/DN DEV +DN
O
51
RMI AC COS
-
24
NOT USED
B
52
CHASSIS GND
I
25
26 VAC_400HZ_H
-
53
NOT USED
O
26
D-DATA
I
54
ARINC 429 IN RM2 A
-
27
Reserved
-
55
Reserved
O
28
D-ENABLE
O
56
BEARING
ROTOR _ MOD
429 _ DISABLE
XFER
RAD
Reserved
SBY / ACT
ILS ENABLE
Continues...
I/O Indications:
150-048500 Rev. H
I = Input
O = Output
B = Both
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
Table 2-1.CVN-251 Pin-Outs (cont’d)
I/O
PIN
I
57
O
58
I
DESCRIPTION
I/O
PIN
DESCRIPTION
O
84
MKR LAMP BLUE
MKR LAMP WHITE
-
85
NOT USED
59
LAMP TEST
O
86
MKR AUDIO LO
O
60
G/S SUPER FLAG
-
87
NOT USED
O
61
TO/FROM +TO
O
88
+10V_AUX
O
62
ARINC 429 OUT A
-
89
NOT USED
-
63
NOT USED
O
90
UP/DN DEV +UP
O
64
TO/FROM +FM
B
91
CHASSIS GND
-
65
NOT USED
O
92
L/R DEV +LT
O
66
NAV AUDIO OUT LO
O
93
RS-232 TX
-
67
Reserved
I
94
RS-232 RX
-
68
NOT USED
-
95
Reserved
I
69
ARINC 429 IN RM1 A
-
96
NOT USED
-
70
NOT USED
I
97
MRK HI/LO SEN
O
71
MRK LAMP AMBER
-
98
NOT USED
-
72
Reserved
O
99
MKR AUDIO HI
O
73
G/S FLAG
-
100
NOT USED
-
74
NOT USED
O
101
NAV SUPER FLAG
O
75
NAV FLAG
-
102
NOT USED
-
76
NOT USED
O
103
ARINC 429 OUT B
O
77
NAV AUDIO OUT HI
-
104
NOT USED
-
78
NOT USED
I
105
+28V IN
O
79
RMI AC SINE
I
106
LBL_033_INHIBIT
I
80
ARINC 429 IN RM1 B
-
81
NOT USED
I
82
ARINC 429 IN RM2 B
-
83
NOT USED
PS _ ENABLE
I/O Indications:
150-048500 Rev. H
I = Input
O = Output
B = Both
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
Figure 2-6 CVN-251 Polarizing Post Assembly
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
D.
(5)
The Interconnect Wiring Diagram Figure 2-2 identifies those wires that must be shielded or
twisted.
(6)
Connect the external wiring to the CVN-251 and associated equipment using the appropriate
interconnect drawings.
(7)
The CVN-251 system can be used with a radio management system or a NAV processor.
Refer to interconnect wiring diagram Figure 2-2 for this type of installation.
(8)
All wiring to be preformed in accordance with FAA-AC-4313-1B, Chapter 11, Section 5.
Antenna Installation
Isolation between NAV receiving antennas is not required. However, recommended distance
between the VHF NAV and VHF COM antennas is at least eight (8) feet. Otherwise, front end
overloading of the CVN-251 receiver circuits may occur during transmit.
Select the NAV antenna mounting areas on the aircraft with the following considerations:
(1)
The VHF NAV antenna should be mounted in the horizontal plane in an area clear of
obstructions omni directionally to the entire aircraft.
(2)
The Glideslope antenna should be mounted in the horizontal plane in an area clear of
obstructions in the forward hemisphere.
(3)
The marker beacon antenna should be mounted on the under surface of the aircraft where it
will receive signals transmitted vertically from ground-based antennas.
The antennas should be mounted on a flat metal surface to obtain a proper ground plane. A
doubler plate may be required to support the antenna if the aircraft skin thickness does not
provide sufficient rigidity.
Antenna couplers may be used to supply a NAV input signal from one antenna to two or
more receivers.
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
E.
4.
Strapping Options
OPTIONAL FUNCTION
STRAP (CVN-251)
Active Frequency Tuning
P1001-34 to ground
System Number "1"
P1001-15 to ground
System Number "2"
P1001-44 to ground
Remote Transfer Function
(Panel or Yoke Mounted)
P1001-13 or P1006-19 to one terminal of a momentary SPST
pushbutton switch SPST pushbutton switch. Remaining switch
terminal is connected to ground.
Marker Beacon Lamp Test
P1001-59 to one terminal of a momentary SPST push-button switch.
Remaining switch terminal is connected to +28 Vdc.
Marker Beacon HI/LO Sens
P1001-97 to one terminal of a SPST toggle switch. Remaining switch
terminal is connected to ground.
Helicopter Rotor Mod Damping
P1001-5 to ground
POST-INSTALLATION CHECKOUT PROCEDURE
A. Visual Inspection
Perform a visual inspection after system installation as part of system checkout.
(1)
Inspect the CVN-251 chassis for dents, cracks and broken cooling fins.
(2)
Inspect the CVN-252 for chassis damage and cracks and scratches on the display.
(3)
Check that the units are properly installed and that thumbscrew hold-down latches are tight.
(4)
Check wiring harness connectors for security and connection to proper unit.
(5)
Check that antenna transmission line connectors are securely fastened and connected to
the proper antenna jack.
(6) Check that cables do not interfere with aircraft controls or other equipment.
B. In-Aircraft Adjustments
There are no in-aircraft adjustments required for the CVN-251. All alignment and adjustment
procedures are accomplished during bench maintenance. However, adjustments may be required
in associated indicator and AFCS equipment. Refer to equipment manuals for these components.
150-048500 Rev. H
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
C. Preflight Check
After completion of the "Post-Installation Check", perform the following preflight check to ensure
that the CVN-251 system is functioning properly.
(1)
Ramp Test Set-up
Several different types of portable test equipment are available for ramp testing the NAV system.
All tests should be conducted in accordance with the operating procedures found in the
instruction manual provided with the test equipment.
Caution:
Keep all equipment turned off during engine starting procedures or while connecting
external power sources.
(a)
Select a location free of electromagnetic interference or reflecting surfaces such as
buildings or other aircraft. Set up the portable test equipment in the vicinity of the
aircraft, and ensure that test equipment is functioning properly.
(b)
Apply ground power to the aircraft. If ground power is not available, ramp check should
be performed with aircraft engine(s) running.
(c)
Apply power to the CVN-251. No warm-up period is required; system operation is
instantaneous upon application of power.
(d)
On the CVN-252 Navigation Control Display unit select the frequency
108.00 MHz.
Select Marker and NAV audio on the Audio Selector unit to be heard over speaker or
phone as desired. Turn up volume.
(2)
Marker Beacon Operation
(a)
Place the Marker Beacon Sens switch in the HI Sens position.
Note: HI Sens threshold is 100 to 400 V into the marker receiver.
150-048500 Rev. H
(b)
Set the test set for an output signal of 75 MHz, modulated 95% by 400 Hz at sufficient
amplitude to energize the marker lamps. The blue marker lamp (OM) on the marker
lamp panel shall light and the 400 Hz tone shall be audible.
(c)
Place the sens switch to LO. The blue lamp shall go off and the tone will no longer be
heard.
(d)
Set tone modulation to 1300 Hz and the sens switch to HI. The amber marker lamp
(MM) shall light and the 1300 Hz tone shall be audible.
(e)
Return the sens switch to LO. The amber lamp shall go off and the tone will no longer
be heard.
(f)
Set tone modulation to 3000 Hz and the sens switch to HI. The white marker lamp (IM)
shall light and the 3000 Hz tone shall be audible.
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
(3)
(g)
Return the sens switch to LO. The white lamp shall go off and the tone will no longer be
heard.
(h)
Repeat steps (2), (4) and (6) at a test set amplitude to energize the marker lamps with
the sens switch in the LO position. (LO sens threshold is 1000 V into the marker
receiver.) The appropriate lamps shall light and tones shall be heard.
VOR Operation
(a)
Set the test set for a standard VOR signal at 108.00 MHz. Set test set bearing to 0 TO.
(b)
Select a CDI course (OBS) of 0°. The VOR deviation indicator shall center and the NAV
flag shall be out of view. RMI systems shall indicate 0. The bearing display on the
CVN-252 shall indicate 0 3.
(c)
Set test set bearing to 10°. The deviation indicator shall deflect full scale to the right.
The RMI and CVN-252 shall indicate 10°.
(d)
Set the test set bearing to 350. The deviation indicator shall deflect full scale to the
left. The RMI and CVN-252 shall indicate 350.
(e)
Set test set for VOR modulation plus 1020 Hz tone modulation. The 1020 Hz tone shall
be audible.
(f)
Adjust the test set for removal of 30 Hz variable phase modulation. The VOR/LOC
warning flags shall come into view.
Note: This test procedure is sufficient to ascertain proper operation of the
CVN-251 System. Steps (1) through (6) may be repeated for several frequencies
and test bearings to thoroughly test the indicator systems.
For tolerances of associated NAV indicators, refer to manufacturers’ specifications.
(4)
150-048500 Rev. H
Localizer Operation
(a)
Set the test set for a standard localizer centering signal at 108.10 MHz.
(b)
On the CVN-252 select a frequency of 108.10 MHz.
(c)
The localizer deviation indicator shall center and the NAV flag shall be out of view.
(d)
Adjust the test set variable LOC deviation signal from 0 DDM to 0.155 DDM,
90 Hz predominating. The localizer indicator shall deflect from center at 0 DDM to full
right at 0.155 DDM smoothly.
(e)
Vary the LOC deviation signal from 0 DDM to 0.155 DDM, 150 Hz predominating. The
localizer indicator shall deflect from center at 0 DDM to full left at 0.155 DDM smoothly.
(f)
Remove test set 150 Hz modulation. The VOR/LOC warning flag shall come into view.
(g)
Reinsert 150 Hz modulation and remove 90 Hz modulation. The VOR/LOC warning flag
shall come into view.
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FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 2 – Installation
(5)
5.
Glideslope Operation
(a)
Set the test set for a standard glideslope centering signal at 334.70 MHz.
(CVN-252 frequency selection remains at 108.10 MHz). The glideslope indicator shall
center and the glideslope flag shall be out of view.
(b)
Adjust the test set variable glideslope deviation signal from 0 DDM to
0.175 DDM, 90 Hz predominating. The glideslope indicator shall deflect from center at
0 DDM to full down at 0.175 DDM smoothly.
(c)
Vary the glideslope deviation signal from 0 DDM to 0.175 DDM, 150 Hz predominating.
The glideslope indicator shall deflect from center at 0 DDM to full up at 0.175 DDM
smoothly.
(d)
Remove the 150 Hz modulation. The glideslope warning flag shall come into view.
(e)
Reinsert 150 Hz modulation and remove 90 Hz modulation. The glideslope warning flag
shall come into view.
FLIGHT TEST PROCEDURE
Upon completion of post installation and preflight checks, a local flight may be made to verify system
operation. System performance may be evaluated by comparing the readout from one NAV system
against another in the aircraft.
150-048500 Rev. H
Page 32
FliteLine CVN-251
VHF Navigation System
Installation Manual
Section 3 – Operation
SECTION 3 – OPERATION
1.
General
Refer to FliteLine Pilot’s Guide, Publication No. 150-047012
150-048500 Rev. H
Page 33