The Marine Reconnaissance version of the Tracker was a CS2F-3 with the A/S electronics stripped out, however much of the communication and navigation electronics in this version could be found in the  anti-submarine version. Unless otherwise noted, the equipment listed in the table below  was derived from the Canadian Forces Pilot Operating Instructions for the CP-121 (CS2F-3) Tracker whose pages are dated 4 December, 1987. If anyone can provide additional details, please contact : jerry.proc@sympatico.ca

Flight Comment Magazine, issue 1990 No 3,  cites the following in an article on the Maritime Reconnaissance version of the Tracker.

“The Tracker was fitted with an OMEGA navigation system and a high powered radar. These allowed positive positions of targets to be ascertained for fisheries or environmental prosecution. For other purposes as directed, a high powered search light along with a day-night photographic system gave the Tracker great flexibility as the squadron operated in all kind of weather and light conditions. The Codfish computer, an onboard computer installed in the Tracker in 1986, was capable of storing communications logs, photos, and holding current fisheries license lists.”
AN/APS-504(V)? This was the radar in the maritime reconnaissance version only. It was used by the AESOP and available at the 4th seat only. Originally designed for antisubmarine warfare applications, it represented the next generation in digital X-band airborne search radar in the mid 1980's era. It also provides the operator with the capability to detect small targets up to 200 - 250 nm and  to conduct search and rescue patrols, maritime surveillance, ice patrols, anti-submarine watch, weather detection, and beacon interrogation.  One of the variants was made by Northrop Grumman Canada, which is now part of L-3 WESCAM, Burlington, Ontario, Canada. Other variants were made by Litton Canada. The variant carried on the Tracker is not known at this time. (Need photos)

Select here for Technical specifications

AN/ARN-504(V)2 TACAN - D/F and DME (Distance Measuring Equipment) . The D/F antenna was atop the cockpit while the DME antenna was on the tip of the tail below the rudder. (Need photo of equipment)
AN/APN-503 Doppler radar. Provides ground speed and track. Operates between 0 to 50,000 feet. Used by Pilot and co-pilot. (Need photo)
AN/R1047A/A The On-Top Position Indicator (OTPI)  is used too provide bearing and on-top position indication of deployed sonobuoys. When used in conjunction with a suitable ADF system, it allows the operator to locate and verify the position of sonobuoys. Max range 26 nm. Used by pilot and co-pilot. (Need photo)
AN/APX-77  Ultra-lightweight IFF transponder manufactured by Hazeltine.  175 nm maximum range. Controls on pilot's overhead console. The APX-77 SIF antenna was located on the vertical fin.

APX-77 Tx/Rx image courtesy  <ham.brugtgrej.dk>
APX-77 combination antenna

AN/ARC-505 This is the Collins 618T-3 HF transceiver.  Frequency Range: 2-29.999 MHz in 1 KHz steps. Modes: AM, CW, USB, LSB, Data. Power requirements:  28VDC or 115 VAC 400 Hz. Power Output AM/CW:  125W. SSB: 400W PEP. Used by AESOP. Reception and transmission available at all positions.

618T/ARC-505   (Photo by John Mackesy VK3XAO)

AN/ARC-511 VHF/AM transceiver. Used by pilot and co-pilot. Controls on cockpit console. Reception and transmission also available in 3rd and 4th seats. (Need photo)
AN/ARC-513 VHF/FM transceiver. Used by pilot and co-pilot. Controls on cockpit console.  Reception and transmission available in 3rd and 4th seats. VHF-FM was used to communicate with ships on commercial marine frequencies (Need photo)
AN/ARC-27A  UHF Transmitter Receiver. RT-178/ARC-27 UHF aircraft receiver-transmitter. Frequency Range 225-399.9 MHz; Modes: MCW/Phone; Power output: 9 watts; 18 preset frequencies on any one of 1750 frequency channels. Transmitter may be tone modulated at 1020 Hz for emergency or direction finding purposes. One guard channel in the 238- 249 MHz range can be simultaneously monitored. Used by pilot and co-pilot. (Reception and transmission available in 3rd and 4th seats in CS2F-3).

ARC-27 unit- exterior (Photo courtesy: www.Radiosamling.dk) 
ARC-27 unit - interior (Courtesy Fair Radio Sales) 
ARC-27 combination antenna

 AN/AIC-8  Interphone. Can support 2 to 15 stations.
Control panel . (Partial photo by Jerry Proc)
AN/ARN-44 Modifed version of AN/ARN-6 radio compass. Band 1 receives 2 to 3.5 MHz instead of 100 to 200 KHz. 
AN/ARA-25 UHF Homing adapter. Requires UHF radio capable of  225-400 MHz reception. Modes: A2, A3. Circa 1952. Provides homing facilities to selected transmitter stations (UHF, OTPI, VHF/FM and VHF/AM) . Used by pilot and co-pilot. Visual display available at 4th seat. Reception available at 3rd and 4th seat. ARA-25 was the only receiver capable of receiving sonobuoy signals. The Maritime reconnaissance version only had 1 sonobuoy in each nacelle.
AN/APN-22  Radio Altimeter. Manufactured by Electronic Assistance Corp. Operates on FM between 4200 to 4400 MHz, 0 to 10,000 feet over land. Up to 20,000 feet over water. Transmitter Power Output: 1w nominal. Accuracy: ± 2 ft from 0 to 40 ft; + 5% of the correct terrain clearance from 40 to 20,000 ft.  A reliability circuit disabled the indicator when the signal is too weak to provide reliable operation. Main units consist of an Electronic Control Amplifier AM-291/APN-22,  Height Indicator ID-257/APN-22, Radar Receiver-Transmitter RT-160/APN-22 

Photo of system components. (Courtesy of Tpub.com)

AN/ARN-503  VOR/ILS and Marker Beacon receiver. VOR provides navigational information. ILS aids landing. The Marker Beacon identifies passage over airway, outer or inner markers. Used by pilot and copilot. Indicators available at 3rd and 4th positions. (Need photo)
AN/ARN-508 ILS Glide Slope Receiver. (Need photo)
AN/ARN-509 Omega Long Range radionavigation receiver. The Omega system, which operated in the 10 to 14 KHz band, was shut down in 1997.(Need better photos)

Photo of front panel.
Closeup of C5306 front panel. (From manual C12-107-000/MB-002) 

VIR-31 Collins navigation radio. The military version of this radio is called the AN/ARN-140 but the Tracker's maintenance manual uses the commercial VIR-31 designator. It indicates use with the AT-640 antenna. 

Photo of unit  (Courtesy Southeast Aerospace)

AN/PRQ-501 Personal Locator Beacon (PLB). Two way radio for voice and homing operating on 243 MHz . A total of 5 were carried. 

Photo of AN/PRQ-501 (Courtesy: Simple Machines Forum)

AN/URT-505 Portable Emergency Locator Transmitter. (ELT). Provides homing transmission on both 121.5 and 243 MHz. Can be used by any crew member.  Located on Third seat bulkhead.  It must be physically turned on by the crew after the antenna is manually attached. (Need photo)
(DAPI 8)
Downed Aircraft Position Indicator. A fixed set which provides homing transmission (only) on 243 MHz. Can be flashed up manually by the pilot or co-pilot or automatically by ground impact or submersion in water. The manual deploy switch was in the overhead pilot's console. Ground impact switches are located in the nose cap and wing tips. A submersion switch was located in the radar dome. (Need photo)
Model unknown "Codfish" Computer. For local on-board storage of communications logs, photos, and holding current fisheries license lists. (Need photo and tech info)

tracker_3_ ant_locations_s.jpg This diagram indicates the placement of antennas on the -3 Tracker in the Maritime reconnaissance variant. It also serves as a guide for the antennas on the -1 and -2 Trackers. Because the Maritime reconnaissance version was based on land, that would account for the fitting of ILS glideslope, ILS localizer and  marker beacon receiver  systems which would not be used for carrier operations.  Click to enlarge. (Courtesy  Canadian Forces Pilot Operating Instructions for the CP-121 [December 1987] provided by Ernie Cable)

Port side view of the rearward pointing ILS Localizer antenna for the AN/ARN-508 set. There is an identical antenna in the same spot on the starboard side. ILS was only fitted to the Maritime Reconnaissance version of the Tracker because the aircraft was land based. ILS is not used in carrier operations.  (Photo by Keith Harrington) 

Credits and References:

1) Ernest Cable Associate Air Force Historian,  Shearwater Aviation Museum <erncar(at)ns.sympatico.ca>
2) AN/APX77 image -  http://ham.brugtgrej.dk/itemshow.php?obj=49420
3) PRQ-501 image
4) Keith Harrington <va7ssb(at)hotmail.com>
5) AN/APS-504   http://www.acq.osd.mil/ott/natibo/BorderSurveillance.pdf
6) AN/APS-504 http://www.provincialairlines.com/AMSDRadar.htm
7) Souteast Aerospace  http://www.seaerospace.com/lc/cart.php?target=productDetails&model=VIR-31H&substring=

Back to Tracker Main Document
March 1/10