HR Smith Products

HR Smith Products (15)

Tuesday, 07 February 2017 12:53

503 Series Deployable ELT

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The need to accurately pinpoint downed aircraft through the use of a Crash Position Indicator (CPI) or Automatically Deployable Beacon (ADELT) has always existed.

The Techtest 503-16 deployable ELT series combines full Cospas/Sarsat coverage together with the transmission of last known GPS co-ordinates to accurately locate downed aircraft.

Features include; on aircraft programming
of Cospas/Sarsat protocols allowing for easy removal and replacement of the beacon,
a modular design allowing for ease of maintenance and a multi-axis programmable G-Switch that ensures reliable operation against CAA Specification 16.

The 503-16 series is utilised globally by all major helicopter manufactures and operators. 

503 series


Brochure downloads

pdf503 Series Tracking ELT
pdf503 Series Deployable ELT 
pdf12-503-5 Programming Test Set 

Friday, 07 June 2013 13:14


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13-150-3 vehicle antennaThe 13-150 series of antennas offers significally reduced visual profile with electrical performance comparable to passive antennas more than twice the size. These antennas are adaptable to multi band frequency requirements with added UHF functionality already acheived within the same footprint.

System Operation
The 13-150 series of antennas utilise advance high speed switching circuitry techniques to achieve high levels of gain performance. This is made possible by each antenna holding an individually programmed EPROM memory device which can store a unique set of antenna calibration data pre-defined for the finalised platform. When the radio is tuned to a frequency it sends a frequency word to the internal Logic Converter Unit, this word is then deciphered into a binary format and enables the antenna to switch to the sent frequency. (All of this process happens in <50 microseconds) As the antenna holds all the calibrated frequency data it enables any antenna to work on any platform without the antenna having to return to the factory.

  •     Low Visual Profile <1 metre
  •     Spring mounted on a NATO four hole base
  •     Specifically designed for use on land and sea
  •     based vehicles
  •     Fast silent tuning less than 50 microseconds
  •     Compatible with frequency hopping
  •     secure speech networks
  •     Unique memory system (allowing 'in theatre'
  •     part swap)
  •     Multi band operation
  •     Out of band signal filtering
  •     50 W CW Power Handling (VTAC)
Typical radio interfaces
Frequency 30-90MHz (VTAC)
  225-450MHz (UHF)
Impedance 50 Ohms
V.S.W.R. ≤ 3.0:1 VHF and UHF
Polarisation Vertical
Radiation Omni
RF Connectors Two(2) TNC Female
DC Connectors MIL Series II
  62GB 12E14-19PN
Colours Nato Green
  (other colours available on request)
Environmental Qualifications: Tested and qualified to MIL-STD 810E
Typical Radio Interfaces Rockwell Collins Flexnet Series
  Rhode & Schwarz M3AR
  Raytheon ARC231 and 232
  Thales TRA5400N
  Elmer SRT651 Series
  Wulfsburg RT5000
  Marconi AD3400
  (Compatible with other radio types on request)
Installation Good electrical contact must be maintained between the antenna base and the vehicle shell
Vendor Code (NSN) K6543
Thursday, 30 August 2012 10:17

Personal Locator Beacon 500-30 Series

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The 500-30 is a direct upgrade replacement for the URT33 and URT44 beacons providing aircrew with a 406MHz with embedded GPS beacon as a plug and play replacement. 

Once on the ground the pilot can utilise the integrated antennas including GPS to provide portable functionality. With visual indicators and audible sounder the beacon provides aircrew with certainty of transmission. Manual control provides the option to suppress transmissions where circumstance requires. 

500-30 Personal Locator Beacon

Automatic activation is available via a lanyard system. The beacon is compatible with pre-existing automatic activation mechanisms on the ACES II/III ejection seats, Martin Baker ejection seats and the BA-22/LPP back style parachutes.

The inclusion of GPS lat/long co-ordinates will provide rescue teams with location accuracy within 100m. In addition, the ability to home onto the established 121.5MHz and 234MHz SAR frequencies. An optional speech capability on 121.5MHz and 243MHz is also available.

  • The 500-30 provides end users with the ability to reprogramme the 406MHz protocol to suit installation.
  • Robust, compact and light-weight
  • 48 hours transmission of 121.5 MHz and 24 hours of 406MHz at -20˚C
  • GPS data transmitted via 406MHz
  • Fully re-programmable 406MHz protocol
  • Optional speech mode on 121.5MHz and 243MHz
  • Simple Built-in-Test function
  • Fully compatible with COSPAS SARSAT system
  • Meets NATO STANAG 7007 and Eurocae ED-62A
  • Interchangeable replacement for URT 33 PLB
  • Manual and multiple automatic activation methods
  • 5 year battery life


Transmitter Signal

The PLB transmits modulated signals on 121.5MHz / 243MHz distress frequencies with characteristics in accordance with STANAG 7007, plus 406MHz in accordance with COSPAS/SARSAT. 

Modulation (121.5MHz / 243MHz)
Continuous Swept Tone of at least 700Hz within the Sweep Range.
Sweep Range 1.6KHz to 300Hz
Sweep Rate 2-3Hz
Amplitude Modulated with Rectangular Wave
Modulation Depth 80% minimum
Modulation (406MHz)
0.5 Secs 5W pulse every 50 secs.
Phase modulation of ±/3 rad (peak)
Digital modulation (see C/S G.005 Iss. 2 Rev 7, Section 3) to include:
 Bit Synchronisation  Frame Synchronisation
 Protected Field  Emergency-Code/National Use Field
 Long Message  
GPS Receiver (Embedded)
Hot Start (avg) <1 sec typical Sat. Signal Reacquisition Time 100ms
Warm Start (avg) <31 sec typical Number of Channels 66(Search) 22(Track)
Cold Start (avg) <31 sec typical Min Signal Level Tracked -165dBw
Receiver L1 C/A Code Power Consumption 13mA
Protocols NMEA  
Power Output
406MHz 24 hours min 5W (+37dBm ±2dBm) at -20 degrees C
121.5/243MHz 48 hours min >100mW (+20dBm) at -20 degrees C
Activation Lanyard
Automatic BA22 Interface / ACES II/III Remote Activation Cable
Martin Baker ejection seats
Dimensions 125mm x 70mm x 33mm nominal
Weight <587g nominal
Colour NATO green/Yellow
The unit is designed to survive for up to 20 years with the only maintenance being battery replacement every five years.
The PLB is compliant with the following specifications:
Military NATO - STANAG 7007 / MIL STD 810G
Part Number
500-30 121.5, 406 & GPS
500-30-B 121.5, 406, GPS & SMB Connector
500-30-C 121.5, 243, 406, GPS, SMB & Speech
500-30-D 121.5, 243, 406, GPS, SMB
500-30-E 121.5, 243, 406, GPS, SMB, Speech & Float

All variants are also available in yellow or with a remote activation cable.

Wednesday, 29 August 2012 15:41

Direction Finding S.A.R.

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direction finding sar

  • Multi-beacon DF
  • Single compact antenna unit
  • High sensitivity receiver
  • Fully COSPAS-SARSAT compatible

The Techtest DF system is designed to reduce the time to locate emergency locator beacons. It is compatible with both 121.5MHz swept tone distress beacons and 406MHz COSPAS-SARSAT transmissions on current and future frequencies.

The user is able to monitor four frequencies and detect emergency transmissions. Each transmission is allocated a unique identification which can then be selected for more detailed information.

For 121.5MHz the system can display relative bearing details.

For 406MHz the system will give all the same information as 121.5MHz but in addition will record and decode the COSPAS-SARSAT message, giving details of the distress beacon and if available the GPS beacon location.

The system comprises of three modules

  • 1. Antenna (10-246-1) The Antenna is a single compact module comprising a circular array of elements with integral high sensitivity receivers. The array is designed todf control panel give optimal angular resolution of the emitters.
  • 2. Control Unit (406-28) The Control Unit takes the array output and, using a digital processing and advanced beam forming technique, is able to discriminate multiple emitters and direction find on the signals. All the data is processed using intelligent algorithms to reduce system noise and spurious responses.
  • 3. Display (407-3) Different display options are available and are platform specific. The basic display module is based on the Techtest 407-2 unit. This unit is designed for ease of use featuring mode and scroll controls and a dual function uncluttered graphic LCD display. A secondary display option is available.

In normal operating mode the DF receiver frequency is switched cyclically between 121.5, 156.8 and 243 MHz. If a signal above the threshhold is detected, a 0.3 second snapshot is recorded before continuing. A separate receiver is used to continuously monitor the 406 SARSAT frequency. If a signal is detected then the DF receiver will immediately switch to 406MHz frequency and record a snapshot. In the event of transmitting beacons incorporating a GPS position, the system will display the applicable lat/long co-ordinates.

Direction Finding / Homing
A 360˚ direction finding facility is provided giving a direction for the aircraft to fly to the transmitting beacon. No other navigation aids are required. If however on board GPS navigation systems are installed in the aircraft, system integration will provide aircrew with both an absolute bearing and distance information to the transmitting beacon.
In the Homing mode the system sequentially scans the distress frequencies and provides a visual display of left/right steer information.

Cockpit Controller / Indicator
The controller / indicator is mounted in the cockpit. There are just two controls : a push button mode selector (switching between Decode and DF modes), a rotary click / push selector providing control of menu options. The unit is designed to operate mainly without user input.
The user can select any of three modes:

  • i)    Left-Right Indicator: To show bearing relative to aircraft heading.
  • ii)   Map display: Showing relative positions, (or bearings), of all detected emitters, both from DF receiver and 406 Decoder.
  • iii)  Text Display: Ideal for 406 decoder information. Can also be used to display range and bearing data.pdf icon
Dimensions Short 3/8 ATR (90x198x322mm)
SAR frequencies 121.5, 243, 156.8, 406 MHz
Training frequencies 4 selectable: 110 to 410 MHz
Sensitivity 2.5μV
DF Accuracy Better than 5˚
Decoder Frequency 406.025 - 406.050 MHz
Message Format COSPAS-SARSAT C/S T.001
Supply Volts 18-36V DC MIL-STD 704D
Antenna 10-246-1
Diameter 250mm
Height Standard 250mm
Reduced 180mm
Polarisation Vertical
Cockpit Controller / Indicator 406-3
Dimensions 146 x 67 x 152mm
LCD Display 56 x 42mm (320 x 420 pixels)
Backlighting NVIS Green B (MIL-STD 3009)
Environmental MIL-STD 810F
Thursday, 15 December 2011 10:49

406 Handheld Decoder

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The 12-406-9 is a handheld 406 decoder that receives and decodes COSPAS SARSAT distress or test messages. The unit can be set-up to monitor all transmissions (including tests) or distress smith 406 decoder
  • COSPAS/SARSAT 406MHz Detection and Decoding
  • Messages decoded and displayed in an easy to understand format
  • Touch screen interface
  • Internal Antenna
  • Internal re-chargeable battery
  • USB to PC connectivity
The need to detect and locate downed aircrew has always existed. Accurately pin pointing both aircraft and crew can sometimes necessitate a lengthy search scenario. The increased population of COSPAS /SARSAT (C/S) 406MHz beacons worldwide is aiding the task significantly. In particular, for those able to transmit with embedded GPS, the potential is there for the land or airborne Search and Rescue (SAR) forces to affect immediate rescue.

The Techtest 12-406-9 is specifically designed to detect, locate, and verify any 406MHz beacon transmission, including ELT or ADELT/CPI and EPIRBs. It can be used either as a test tool on the ground or as portable equipment on a SAR mission.  It is able to immediately display the transmitted GPS Lat/Long location of the beacon if present and, in conjunction with the built in GPS receiver, display range and bearing information.

The handheld unit includes a colour touch screen providing a clear display of information with user configurable fields. The integral antenna results in a compact device easy to carry. Data is updated continuously as new messages are received and decoded (typically every 50 seconds from one beacon). If multiple beacons are transmitting then all are summarized on a scrolling display. Individual messages can be selected to display full decode information. Data can be transferred to a PC for later analysis.

The unit can be fixed to a wall, using an optional mounting tray, and configured as a remote monitoring station.  In this case data is logged automatically by a Windows Based Application.
Monday, 04 October 2010 15:27

Test Equipment

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12-602-8 cable antenna analyzerAs manufacturers of antennas and SAR equipment, the company has always believed it of great importance to provide supporting equipment to these products. Over the years, this has resulted in a range of Test Sets being manufactured by Techtest.

Our range of VSWR Test Sets is known throughout the aviation community as the industry standard products for testing aircraft antennas. They are all available with ruggedized cases and models are available to cover all the frequencies commonly found in avionic equipment. These VSWR Test Sets allow antennas to be checked for correct operation and can be used whilst the antenna is still on the airframe thus saving costly removal of the antenna when it is not necessary.

It is vital that an Emergency Locator Transmitter works correctly, if it is used, so Techtest supply a range of test equipment to check correct operation of this type of equipment. These Test Sets can be used with all types and makes of ELTs and EPIRBs.

Brochure downloads

pdf12-602-8 Antenna and Cable Analyzer (PDF)  
pdf12-406 Homing Test Set (PDF, 436Kb)
pdf12-500-5 PLB / ELT Test Set (PDF, 60Kb)
pdf12-503-1 PLB / ELT Test Set (PDF, 60Kb)
pdf12-503-5 Programming Test Set (PDF, 84Kb)
pdf12-612 Electrostatic Discharger Test Set (PDF, 840Kb)
Monday, 04 October 2010 15:09

Homing Systems

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The need for Search and Rescue (SAR) services to accurately detect and locate the distress signals from emergency beacons resulted in Techtest developing its range of Homing Systems.

These use a phase comparison method to provide left-right steering information, to the SAR pilot enabling him to locate emergency beacons operating on all the standard distress frequencies (121.5 MHz, 156.8 MHz, 243 MHz and 406 MHz). This type of system requires only two antennas and offers a more compact, lower cost solution to the more complex DF systems available.

 Techtest now manufactures a range of Homer/Decoder systems which decode the unique data included in the COSPAS-SARSAT 406 MHz distress signal. This includes the position infor406-2-053 homing systemsmation from Location Protocol Beacons and gives the user real time information to help minimise rescue times. A number of integrated airborne systems are available as well as the unique Portable 406 SAR Decoder which is a fully self contained unit which can be carried on to any aircraft, boat or land vehicle. This unit is ideal for a SAR force which already has Homing/DF systems fitted but wishes to extend its capability to include 406 MHz decoding in a cost effective way.

Brochure downloads

pdf12-406-7 Portable 406 SAR Decoder (PDF, 160Kb)
pdf12-406 Homing Test Set (PDF, 436Kb)
pdf406-2-053 Full NVIS Compatibility SAR Homing System (PDF, 284Kb)
pdf406-407 Delivering real-time SAR 406 decode and position (PDF, 520Kb)

Monday, 04 October 2010 14:43

503 Series ELT Tracking System

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503 seriesThe Next Generation of ELT

The latest upgrade to the HR Smith 503 ELT series utilises the Iridium satellite network to provide an independent aircraft tracking and alerting function.

The addition of the Iridium service to the existing full Cospas/Sarsat coverage and transmission of last known GPS co-ordinates hugely increases the probability of accurately locating downed aircraft. The Iridium module allows for live aircraft tracking and can be programmed to activate the ELT under abnormal events.

Autonomous Tracking trigger events include:

  • Loss of aircraft power
  • Unusual altitude, attitude, speed or acceleration.
  • Diversion from geo-fence or flight path Plus many other programmable parameters 

If any of these user defined thresholds are exceeded the ELT will be activated. A Distress Tracking option is also available, which activates the ELT in the event of an imminent accident. The activation triggers for distress tracking are designed to meet EUROCAE ED237. Existing 503 series ELT customers wanting to upgrade to the Iridium functionality need only replace the G-Switch module and Antenna, due to the unique modular construction of the 503 series ELT system. The 503 series is utilised globally by all major rotary and fixed wing manufactures and operators. 

elt tracking

Brochure downloads

pdf503 Series Tracking ELT
pdf503 Series Deployable ELT 
pdf12-503-5 Programming Test Set 

Monday, 04 October 2010 00:00


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The 500 series of Personal Locator Beacons or Survival Emergency Locator Transmitters offers a wide range of options to suit any requirement. The 500 series of Personal Locator Beacons has been chosen by a wide customer base, including armed forces, commercial airlines, off-shore helicopter operators, life raft manufacturers and ejection seat manufacturers.

For all the 500 series Personal Locator Beacons, Techtest has obtained full certification to aircraft standards so these products should not be confused with inferior quality beacons intended for hobby use.

The 500-1 Personal Locator Beacon is a compact light-weight unit operating on 121.5 MHz and 243 MHz and has been favoured by customers requiring a small beacon for many years.

The 500-12 Personal Locator Beacon is designed to work with the COSPAS-SARSAT search and rescue satellite system and features 406 MHz as well as 121.5 MHz and 243 MHz distress signals. It also incorporates a speech function which allows survivors to have two way voice communication with a rescue craft. In addition to the normal aircraft approvals the 500-12 also has full Boeing and Airbus approvals making it the natural choice for commercial airline operators due to its compact size and low weight. The 500-27 shares all the functionality of the 500-12 but also incorporates embedded GPS to minimize location time in the event of an emergency.

The latest 500-27-07 PLB (above right) utilizes all the proven electronics of its predecessors but updates the casing design to give a modern stylish appearance without losing the rugged and durable qualities associated with Techtest SAR products.

The new 500-32 PLB (above left) offers similar features to the 500-27-07 but in a significantly smaller package (35% reduction in volume). This has been achieved by using state-of-the-art battery technology and optimised electronics.

After rigorous testing the 500-32 series of ELT(s) or PLB has recently been awarded a COSPAS SARSAT type approval (Certificate No. 223).

500-30, 406 MHz Ejection Seat Compatible PLB

The 500-30 is the latest member of the highly successful Techtest PLB range offering 406MHZ transmission and Guard frequency transmission combined with embedded GPS to
500-30 provide positional accuracy of 100m.

With both manual and automatic activation capability the beacon offers maximum flexibility across a fleet of aircraft. Providing interface solutions for inclusion in PSPs within ejection seats such as ACES II/III and in combination with parachute activation mechanisms such as the BA22. Once activated upon ejection the PLB will transmit SAR frequency signals via remote antennas allowing rapid recovery.

Once on the ground aircrew can continue to transit using remote or integrated dual frequency antennas including GPS providing portable functionality and the ability to control beacon transmission according to circumstance. With 5 year battery life, 48 hours transmission on 121.5MHz and 24hours on 406MHz at -20 °C the 500-30 meets COSPAS SARSAT, ED-62A, STANAG 7007 and MIL-STD 810F specifications.


Brochure downloads

pdf500-12 Multi Function Personal Locator Beacon
pdf500-27 Multi Function Personal Locator Beacon + Embedded GPS
pdf500-27-07 Multi Function Personal Locator Beacon + Embedded GPS
pdf500-30 Multi Function Personal Locator Beacon
pdf500-32 406MHz Multi Function Personal Locator Beacon
pdf12-503-5 Programming Test Set

Monday, 04 October 2010 14:11

Static Dischargers

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dischargersFor many years, HR Smith (Technical Developments) have been manufacturing a range of Static Dischargers for all aircraft platforms from GA aircraft through commercial airliners to fast jet applications.

The company manufactures a version of its range of dischargers by conventional techniques using aluminium castings with composite rods but has pioneered the introduction of its range of all plastic static dischargers. This type of discharger is manufactured from advanced thermo-set plastics and offers a number of advantages over the conventional design. These include light weight, improved noise resistance, lightning strike resistance and low cost of ownership.

Brochure downloads

pdf12-612 Electrostatic Discharger Test Set (PDF, 840Kb)
pdfA revolutionary advance in electrostatic dischargers (PDF, 1Mb)

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