BS4-05

BS4-05 matching module for aircraft systems

BS4-05 is a specialized aviation matching module used for processing and coordination of electrical signals from SKT-type sine-cosine transformers. The unit belongs to aviation technical property and is used in onboard electronic equipment and automatic control systems of aircraft and helicopters. In the supplied context, the module is associated with Mi-26 heavy transport helicopters and related Russian / Soviet aviation equipment. The module provides signal matching between angular-position sensors and the onboard systems that use this information.

Function of BS4-05

The main function of BS4-05 is matching and conversion of information signals that carry angular position data. These signals are received from SKT sine-cosine transformer sensors and prepared for further transmission to onboard systems. Depending on aircraft configuration, the receiving systems may include flight-navigation equipment, automatic control systems or flight data acquisition / monitoring equipment. Correct operation of the module is important where angular position signals must be transferred with stable scaling, phase coordination and low conversion error.

Operation with SKT sine-cosine transformer signals

BS4-05 works with electrical signals generated by SKT-type sine-cosine transformers. These sensors are used to transmit angular position information in aircraft equipment. The module processes sinusoidal and cosinusoidal components and coordinates them for use by connected avionics or control circuits. According to the supplied context, the input signal frequency is 400 Hz, which corresponds to the standard aircraft AC network frequency used in many onboard systems. Exact circuit levels and connector pinout should be confirmed through original documentation.

Application on Mi-26 and related equipment

The BS4-05 module is referenced in the context of Mi-26 helicopter onboard equipment and repair documentation. It may be used as part of systems requiring accurate transformation or matching of angular-position signals. The module is also mentioned together with related aviation matching blocks such as BS2-01 and BS4-04, as well as automatic control system modules. Since actual installations may differ by helicopter configuration, equipment version and maintenance documentation, applicability should be confirmed through the aircraft equipment list and technical documentation.

Technical documentation and maintenance

The module is associated with technical specifications TU 8I3.048.008TU and drawing / part number 8I3.048.008. Full engineering data, including connector pinout, bench-test procedure, exact conversion tolerances and control-point values, should be taken from the original operating and maintenance documentation. During inspection, the module should be checked together with SKT sensor lines, connectors, wiring harnesses, receiving avionics units and any related automatic control or recording equipment. Test records and passport data are important for acceptance.

Identification and ordering of BS4-05

Before ordering BS4-05, the aircraft type, system application, required quantity, condition category and documentation requirements should be confirmed. The customer should also clarify whether only the BS4-05 module is required or whether related modules such as BS2-01 or BS4-04 are also needed. The item may be supplied for repair stock, scheduled maintenance, replacement of a defective matching module or restoration of Mi-26 onboard electronic systems. Passport, form record, acceptance stamp and test documentation should be agreed before shipment.

Product Type: Matching module / aircraft electronic signal conversion unit
Designation: BS4-05
Russian Designation: БС4-05
Alternative Product Names: Matching block, matching module, SKT signal matching unit, electronic module, aviation technical property module
Function: Matching and conversion of angular-position information signals from SKT-type sine-cosine transformers
Application / Where Used: Aircraft onboard electronic equipment and automatic control systems
System / Installation Area: Avionics, flight-navigation systems, automatic control systems or flight data acquisition equipment according to aircraft configuration
Compatible Aircraft / Equipment: Mi-26 heavy transport helicopter according to source context and documentation
Associated Sensors: SKT-type sine-cosine transformers
Related Modules: BS2-01, BS4-04 and related automatic control system modules according to source context
Drawing / Part Number: 8I3.048.008
Russian Drawing / Part Number: 8И3.048.008
Technical Specifications: TU 8I3.048.008TU
Russian Technical Specifications: ТУ 8И3.048.008ТУ
Registration Number: B-05878 / Б-05878 according to source context
Input Signals: Sine-cosine transformer voltages
Input Signal Frequency: 400 Hz
Conversion Accuracy: High-precision matching; allowable angular error specified in angular minutes according to source context
Operating Temperature Range: −60 °C to +60 °C
Vibration Resistance: Designed for aviation vibration conditions, including helicopter equipment use
Assigned Service Life: According to the service life of associated onboard automatic control systems, as specified by documentation
Documentation Set: Individual passport / form record, quality control stamp and military representative acceptance stamp where applicable
Condition: New / As-Stored / Overhauled / Serviceable, depending on availability
Technical Documentation: Product passport, form record, TU 8I3.048.008TU, aircraft system documentation, wiring diagrams and bench-test records if available

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In Stock — items available in stock at the Dubai warehouse are dispatched within 5–10 business days after receiving 100% prepayment.

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Returns & Changes (Restocking Fee)
For selected items, a RESTOCKING FEE of 10% may apply in case of return, order cancellation, or changes to the order specifications. This condition applies only to certain products and is confirmed at the order approval stage.

Warranty
All products are covered by a standard 6-month warranty.
Extended warranty is available upon request and is agreed individually; it may affect the final product price.