LDM #169: Aircraft Servo Potentiometer Type 6A/4725 Teardown and Tests Le labo de Michel 2021-05-09 | This video shows the teardown and some tests of a vintage device used for temperature measurements.A galvanometer system is used to convert a thermocouple voltage into a DC current.Supposed functioning:The thermocouple voltage is fed to the moving coil of the galvanometer which generates a torque. A metallic disc is attached to the shaft of the moving coil. A circular coil with around 10 turns closed to this disc has two functions:- it is used as a torque feedback in order to balance the torque generated by the moving coil- it is used as a detector. The coil is a part of a high frequency oscillator, the distance between the disc and the coil permits to de-tune the oscillator by changing its reactance and therefore introduces a change of the DC anode current of the oscillator.An equilibrium is obtained, the anode DC current is proportional to the input voltage applied to the moving coil.A dual triode is used on this system. One half seems to be used for power supply rectifying, the second half for the oscillator / feedback current. The anode current flows trough the feedback coil and is the output of the measurement. A small transformer is used for power supply. One winding is used for the heaters, a second one for the high voltage (around 80VDC after rectifying).
LDM #380: Kollsman CPU-46/A-22 Military Computer - Part 1: teardown and reverse engineering Le labo de Michel 2024-10-09 | This video shows the teardown and the reverse engineering of a Kollsman CPU-46/A-22 Computer used in military aircraft RF-8G and F-8J/K/L. This vintage electro-mechanical computer permits the computation of the altitude. A correction of the static port according to the Mach number is present. 00:00 - Intro01:43 - Teardown06:13 - Dual synchro system06:48 - Reverse engineering : dual synchro system08:44 - Static Source Error Correction (SSEC)11:35 - Mach number computation and SSEC cam14:29 - Output synchro and digitizer15:22 - Servo monitor circuitsSchematic diagram:https://mwblog.fr/wp-content/uploads/2024/10/CPU-46.pdf
LDM #379: Teardown of a vintage Honeywell 3 Axes system Le labo de Michel 2024-09-28 | 00:00 - Intro01:01 - Teardown04:09 - Electronic boards06:43 - Electronic time interval generator13:30 - Programming panel15:58 - Analog boards
LDM #378: ДЛУММ-30 (DLUMM-30) Servo Accelerometer Le labo de Michel 2024-09-19 | Errata: the range of this accelerometer is +/-30g not +/-20g as I said in the test section at 11:05. Therefore an acceleration of +/-1g corresponds to an output voltage of +/-0.167V.00:00 - Intro01:11 - Teardown02:13 - First analysis04:17 - Electronic boards05:29 - Reverse engineering07:40 - Test coils08:46 - Faulty detector11:05 - Bypassing the faulty detector11:23 - TestThis videos shows technical details about a Russian servo accelerometer ДЛУММ-30 (DLUMM-30). This accelerometer was installed inside a 9E420 radar seeker.How it works:A mass translates the acceleration into a torque which is balanced by a second torque generated by two coils. A sensitive zero detector detects any deviation of the moving mass from the zero position. The resulting voltage is amplified and fed to the torque generator, keeping the mass at the same zero position.The zero detector uses two variable transformers. The primaries are supplied with an ac voltage at 830 kHz. A small piece of copper mechanically linked to the moving assembly penetrates between the primary and the secondary, which modifies the differential induced voltage.Schematic diagram:
LDM #377: ДУСУ1-30В (DUSU1-30V) Russian angular rate gyro - Part 1 Le labo de Michel 2024-09-14 | 00:00 - Intro01:00 - Draining the damping oil02:04 - Opening the gyro03:48 - Torque motor06:44 - Test setup07:28 - First test
LDM #376: Jaeger Fuel Flow Indicator - Teardown, test and reverse engineering Le labo de Michel 2024-09-04 | This video shows the teardown and the test of a fuel flow indicator P/N 65691-005-1 manufactured by the French company Jaeger in the 80s. The last part shows the schematic diagram with explanations.00:00 - Intro00:40 - Teardown02:45 - Power Supply board03:15 - Servo Amplifier board03:31 - Fuel flow rate and logic board05:58 - Test08:45 - Reverse engineering - Part 1: analog display10:25 - Digital input circuit11:44 - Gate and averaging circuits13:11 - FF rate and display update rate15:51 - Counters reset signal16:24 - Scrolling detection17:40 - Counters and display19:34 - Clock generatorConnector pinout:A-B: Lighting, 5VrmsD-K: 115Vac 400HzJ: input commonH: analog input, 0 to 5VC: digital input, 2.27Hz square wave for 1,000. Display proportional to input period. Hi level 6V min.How it works:There are 2 two separate inputs. The first one is a DC voltage from 0 to 5V which permits to set the needle between 0 and 12,000 kg/h. Its uses a torque motor with an embedded potentiometer for the feedback. A servo amplifier permits to set the needle according to the input voltage.The second input is a square or rectangular signal. The clock signal is fed to three CD4518 counters gated by the input signal. An averaging of 10 is performed by counting 10 input cycles and by dividing the counts by 10. A the end of the counting a load signal permits to update the coding wheels display.The display rate depends on the rate of change of the fuel flow. A differentiator is used to get an image of the variation of the fuel flow with time. This signal is fed to a Voltage Controlled Oscillator which gives the maximum update rate of the display.The rightmost digit scrolls when there is a variation of the fuel flow.Schematic diagram:https://mwblog.fr/wp-content/uploads/2024/09/Jaeger_FF_Indicator_A.pdf
LDM #375: Boeing 727 EPR Indicator - Part 1: Teardown and Reverse engineering Le labo de Michel 2024-08-28 | This video shows technical details of an aircraft instrument manufactured by Spirent in the 90's. This instrument is an EPR indicator, Engine Pressure Ratio. On this first episode there are two sections. The first one shows the internal construction. The second section shows the complete schematic diagram with explanations.The second episode will show the code disassembly and I hope the complete test of this unit using an ARINC429 test generator.00:00 - Intro01:05 - Teardown02:54 - Interface board03:35 - MPU board04:57 - Power supply and stepper motors driver board06:43 - Display board07:40 - Preliminary test10:15 - Display testReverse engineering:10:50 - MPU board12:27 - ARINC429 Interface Board15:50 - Luminosity control17:39 - Power down detection18:15 - Display boardSchematic diagram:https://mwblog.fr/wp-content/uploads/2024/08/B727-EPR-A.pdfBlog:https://mwblog.fr/ldm-375-boeing-727-epr-indicator-part-1-teardown-and-reverse-engineering/
LDM #374: Humphrey directional gyro - teardown, test and reverse engineering Le labo de Michel 2024-08-22 | In this video I study and operate a vintage directional gyroscope DG11-0105-1 manufactured by Humphrey Inc., San Diego, California. The heading is slaved to a flux detector connected to the gyroscope. A test is performed using an HSI Collins 331A-8K.00:00 - Intro00:40 - Teardown03:34 - First test and gyro precession04:50 - Final test with magnetic compass and Collins HSIReverse engineering:06:32 - Part 1: overview07:12 - Part 2: power supply07:44 - Part 3: inner gimbal horizontal stabilization08:48 - Part 4: input filter10:53 - Part 5: amplifier and phase detector12:29: Part 6: high speed slaving13:27: Part 7: reference signals generatorHSI Collins 331A-8K:youtu.be/E4v6DHBhFQsSchematic diagram :https://mwblog.fr/wp-content/uploads/2024/08/DG11-0105-1.pdfBlog:https://mwblog.fr/?p=804&preview=true
LDM #373: analysis of a 9E420 Radar seeker electronic board Le labo de Michel 2024-08-15 | After some researches this board is used in a 9E420 radar seeker: ausairpower.net/PVO-SV/9M317E-Buk-M2E-9E420+Slantets-1S.jpgThis board is probably involved in the servo control of the antenna position. 00:00 - Intro 01:57 - Inside the shield 02:47 - Reverse engineering 04:07 - Attenuators 04:36 - Amplifiers and bad guarding tracks 05:44 - Analog switch control 05:58 - Colpitts oscillator 07:15 - Oscillator testSchematic diagram in pdf: https://mwblog.fr/ldm-373-analysis-of-a-kh-101-missile-electronic-board/
LDM #372: Fiber Optic Gyro ТИУС500 and Tornado-S missile IMU Le labo de Michel 2024-08-09 | This video shows some details about the Russian Fiber Optic Gyro ТИУС500 (TIUS500) which was described in the second part of the video #356. The first part of this video shows briefly the FOG installed in the gyro assembly of a Tornado-S Russian missile. The second part of the video shows the schematic diagram with explanations obtained after three days of reverse engineering.00:00 - Intro00:05 - Fiber Optic Gyroscope ТИУС500 (TIUS500)04:28 - Tornado-S IMU06:35 - Reverse engineering - photodiode amplifier & ADC07:07 - Reverse engineering - phase modulator circuits07:39 - SLED temperature regulation10:16 - SLED light power regulation11:48 - System ADCFirst part:youtu.be/Ac2ioGwfsbISchematic diagram and blog:https://mwblog.fr/ldm-372-fiber-optic-gyro-and-tornado-s-missile-gyro-assembly/
LDM #371: Boeing 727 EGT Indicator Le labo de Michel 2024-08-01 | 00:00 - Intro00:38 - Teardown05:21 - Test08:01 - Piecewise amplifier11:30 - Reverse engineering11:41 - Power Supply12:10 - Reference voltages12:35 - Main circuits13:00 - Front-end amplifier14:21 - Piecewise Amplifier circuitsConnector Pinout:1-2: Lighting 5Vrms3-4: 115Vac 400Hz5: Thermocouple (-)6: Thermocouple (+)7: Mechanical ground
LDM #370: Boeing 757 standby engine instrument - Teardown, reverse engineering and test Le labo de Michel 2024-07-25 | This video shows the teardown and test of a Boeing 757 cockpit standby engine instrument, model S231n001 manufactured by General Electric. The schematics with explanations are given at the end of this video.00:00 - Intro01:17 - Teardown02:29 - EGT board04:05 - Cold junction compensation05:37 - EPR board06:47 - N2 board08:27 - N1 board08:45 - Tests11:34 - Self-test12:00 - Reverse engineering: PS board12:39 - Reverse engineering: EGT board16:49 - Reverse engineering: N2 board
LDM #369B: Shahed-136 drone - Air Data Computer Pressure sensor Le labo de Michel 2024-07-19 | This video shows some details regarding the pressure sensors used in the air data computer described in video #369 Links:Sensor datasheet:mouser.com/datasheet/2/589/SM5812-254991.pdfPart 1:youtu.be/PI8aGYTlvJQ
LDM #369: Shahed-136 drone Air Data Computer module Le labo de Michel 2024-07-12 | This video shows the analysis of the air data computer used in the Shahed-136 kamikaze drone.00:00 - Intro00:05 - Board overview01:50 - Preliminary test02:27 - Reverse engineering03:36 - TestNotes:This link shows a transmission format identical to the messages sent by this air data computer:wokwi.com/projects/374500929580971009Blog and schematics:https://mwblog.fr/ldm-369-shahed-136-drone-air-data-computer/
LDM #368: Sperry AD-300C Attitude Director Indicator - Teardown and test Le labo de Michel 2024-07-03 | This video shows the teardown and test of an Attitude Director Indicator model AD-300C manufactured by Sperry.00:00 - Intro00:56 - Teardown02:25 - No gear train02:50 - Test05:53 - Attitude circuits modular circuitNotes:* This ADI uses a DC motor for the roll control and a torque motor for the roll* There is no gear train, the motors are directly linked to the gimbal for the roll and to the sphere for the pitch. This permits to save some weight and cost, the counterpart is the lack of stability when quick change of pitch or roll accurs. However this shouldn't be a problem with commercial aircraft.* The electronics use mainly potted modulesPinout:26-27-28: roll synchro input29-30-31: pitch synchro input10: 28V attitude enable signal (from vertical gyro)
LDM #367: Shahed-136 kamikaze drone servomotor Le labo de Michel 2024-06-22 | This video shows the teardown, the reverse engineering and the test of a servomotor used in the Iranian Shahed-136 kamikaze drone (also called Geranium-2) .00:00 - Intro01:46 - Teardown02:36 - Electronic board03:16 - Test06:15 - Reverse-engineering - overview06:47 - Reverse polarity protection08:15 - Power supply08:54 - Brushless motor power stage10:03 - PWM input interface10:27 - Feedback device10:46 - Feedback output circuitactive parts used:SED10070GG: N-channel MOSFET (x7)lcsc.com/datasheet/lcsc_datasheet_1912111437_SINO-IC-SED10070GG_C396083.pdfSGM8591: Single-Supply, Single Rail-to-Rail I/O Precision Operational Amplifiersg-micro.com/rect/assets/c8325911-0f35-4c14-a4b8-98828013d197/SGM8591.pdfEG2134 芯片用户手册 三相独立半桥驱动芯片lcsc.com/datasheet/lcsc_datasheet_2304140030_EG-Micro-EG2134_C480661.pdfTLP2361eu.mouser.com/datasheet/2/408/TLP2361_datasheet_en_20151102-1079441.pdfXL7005A - 0.4A 150KHz 80V Buck DC to DC Converter lcsc.com/datasheet/lcsc_datasheet_1811081614_XLSEMI-XL7005A_C50848.pdfBlog with schematic diagram in pdf:https://mwblog.fr/ldm-367-shahed-136-kamikaze-drone-servomotor/Link to schematic diagram:https://mwblog.fr/wp-content/uploads/2024/06/LDM367-Shahed-136-servomotor_B.pdfThe servo is similar to the giant scale servo from Hitec ref HS-1005SGT:hitecrcd.com/products/servos/digital/sport-giant/hs-1005sgt-industrial-grade-giant-scale-servo/product
LDM #366: Aircraft Coffee Maker Part 2: reverse engineering Le labo de Michel 2024-06-02 | 00:00 - Intro00:19 - VG1000J unknown part (actually VQ1000J)01:46 - Schematic diagram overview02:38 - Power supply04:31 - Modifications for 115/230V 50/60Hz07:07 - AC-DC converter assy08:03 - Temperature controller10:22 - Crowbar circuits11:42 - Logic circuits14:28 - Capacitive probe fontendNotes:The supposed VG1000J is actually a VQ1000J:vishay.com/docs/70226/70226.pdfBlog:https://mwblog.fr/ldm364/
LDM #365: Atlas launcher gyro part 3: demodulator reverse engineering using X-ray Cheetah EVO Le labo de Michel 2024-05-19 | This video shows the reverse engineering of the demodulator module of a vintage gyro subsystem GR 10A-1 manufactured in 1965 and designed for an Atlas Launch Vehicle.00:00 - Intro01:26 - X-ray analysis using XYLON Cheeta EVO04:07 - Preamplifier07:53 - Complete schematic diagram08:39 - ModulatorMerci à la société Inovelec pour avoir consacré un peu de temps à l'inspection aux rayons X de ce module, ce qui m'a permis d'effectuer la rétroingénierie de celui-ci.inovelec-groupe.comOther episodes:youtu.be/Y11XXXc7LKYyoutu.be/_EgoEV346tY
LDM #364: Aircraft Coffee Maker Part 1: overview Le labo de Michel 2024-05-13 | This video shows the internals of an a coffee maker used in Boeing and Airbus aircraft.00:00 - Intro00:45 - Front panel02:29 - Heaters and possible modifications for 115/230 50/60 Hz05:18 - Electronic boards
LDM #363: Atlas launcher gyro part 2: synchros and spinning test Le labo de Michel 2024-05-08 | 00:00 - Intro00:03 - Outer gimbal synchro test01:02 - Inner gimbal synchro test02:00 - Slip ring contact pinout04:48 - Gyro rotor spinning test
LDM #362: Atlas Launch Vehicle Attitude Reference Subsystem Gyro - Part 1: teardown Le labo de Michel 2024-04-27 | This video shows the teardown of a vintage gyro subsystem GR 10A-1 manufactured in 1965 and designed for an Atlas Launch Vehicle.00:00 - Intro03:25 - Teardown05:51 - Draining the oil08:48 - Gimbals resolvers and torque motors
LDM #361: Analysis of a military electronic boards assembly Le labo de Michel 2024-04-12 | This video shows the analysis and reverse engineering of an electronic assembly which was supposed to be inside a Ukrainian "Stugna-P" missile launcher.One board contains an Atmel ATMEGA168 micro-controller which is connected to a MEMS rate gyroscope and one MEMS accelerometer. The gyroscope is soldered on a small pcb which is mounted on a small mechanical assembly. The angle of the gyroscope can be adjusted using two screws.Another board permits the servo control of the position of something linked to a brushless motor.00:00 - Intro02:04 - Gyro and accelerometer processing board04:45 - Interface / DSP / CPU board03:36 - Brushless motor servocontrol05:39 - Reverse engineering: MEMS Gyro assembly06:04 - MEMS Accelerometer06:28 - Microcontroller Atmega16807:12 - Ribbon cable interface08:04 - Servo control board overview08:49 - MC33035 Brushless DC motor controller10:15 - DAC circuits11:27 - Summing amplifier and phase correction12:47 - Absolute value circuit
LDM #360: Reverse engineering of a Russian missile electronic board #1 Le labo de Michel 2024-03-22 | This video shows the reverse engineering of a Russian electronic board. The reference of the board is "TDCK". It is the power supply board of a satellite communication receiver used in several Russian missiles.We can can this receiver in a Tornado-C missile for instance (Торнадо-С).Video: youtu.be/xJyV7AGPT_4?si=R-ju1wXSOHIxuqTy&t=19800:00 - Intro00:04 - Overview05:08 - Reverse engineering part 1: overall description06:07 - part 2: 12V DC-DC converter09:05 - part 3: voltage monitor circuits13:14 - part 4: 3.3V and 5.0V DC-DC converters13:57 - part 5: DC-DC converters shutdown circuits16:00 - part 6: standby power supplyErrata:Due to an error during reverse engineering the networks Diode-Resistor-Capacitor are actually snubbers connected in parallel to each transformer primary. Nothing is connected to the gate of the MOSFETs.Notes:Most parts are US or European parts. It is obvious that Russia don't have the modern technology to design such board with their own parts.Russian parts:* The toroidal transformer* The 10A fuse* Maybe the electrochemical capacitorMain parts used on this power supply:* UCC28084 (Texas) PWM controller for the 12V power supply* TPS54356 and TPS54357 (Texas) PWM controllers for 3.3V and 5V Power Supplies* MAX974 (Analog Devices) Quad comparators with internal voltage reference* IRF7328 (Infineon) dual P-channel MOSFET* MJD112 (ON Semi) NPN Darlington* FDS4488 (On Semi) N-channel MOSFET* IRFR5305 (Infineon) P-channel MOSFET* SI4156 (Vishay) N-channel MOSFETWeird things:* The grid of one unused MOSFET is left open* What is the purpose of the fuse ? What will happen to the missile if the fuse blows ?
LDM #359: RAF Avro Vulcan Ground Position Indicator - MK.4 - Part 1 Le labo de Michel 2024-02-26 | This video presents the teardown of a vintage Ground Position Indicator which was used in Avro Vulcan aircrafts.If someone knows something about this device please let me know, particularly the purpose of the various controls on the front panel.00:00 - Intro03:54 - Teardown05:16 - Disc & Ball integrator07:33 - Mileage computations13:44 - Normal / Fix modes15:16 - Synchronous motor16:14 - Test with manual heading change17:26 - Mileage simplified electro-mechanical diagramNotes: - At that time the goal of the third disk and ball integrator (on the bottom side) is unknown Edit 07/03/24: according to @Pulsynetic the disk and ball integrator is used for a cosecant function which permits the correction of the meridians convergency to give the longitude.- On the simplified electro-mechanical diagram the outputs of the disk and ball integrators are not the latitude nor longitude but the E-W and N-S mileages.Mileages computation:The mileages are computed using two disc and ball integrators. The disc of each integrator is linked to the same M-type stepper motor. The frequency of the signals which drive the motor must be proportional to the ground speed.The input of the integrator (the displacement of the balls) is an image of the sine and the cosine of the heading. This is simply done using slides and levers linked to the heading shaft.The angle of the output shaft is therefore an image of the integral of V(t)*sin(Theta(t)) and of V(t)*cos(Theta(t)), that is to say respectively the mileage on each axis.Links:Dead reckoning on Wikipedia:en.wikipedia.org/wiki/Dead_reckoning#:~:text=In%20navigation%2C%20dead%20reckoning%20is,course)%2C%20and%20elapsed%20time.Disc and ball integrator on Wikipedia:en.wikipedia.org/wiki/Ball-and-disk_integratoron YT:youtube.com/watch?v=s1i-dnAH9Y4&t=1853sOther navigation computers on my channel:youtu.be/cUOpCMj17Cwyoutu.be/cpOrcHsgwJYyoutu.be/TJI_owLNPZgBall resolver:youtu.be/SKPPBgBhxNsTHE V-FORCE : 1955 to 1966http://www.blackmanbooks.co.uk/navigation.htmlBook Computing mechanisms and Linkages by ANTONÍN SVOBODA (1965)randomwraith.com/documents/Svoboda-ComputingMechanismsLinkages.pdf
LDM #358: Marconi BMETS Meteorological Computer Interface Unit Le labo de Michel 2024-02-17 | This video shows the teardown of a GEC-Marconi military computer. It is a part of the BMETS system which permits the measurement of meteorological parameters for missile flight optimization.00:00 - Intro01:31 - MPU13P board04:02 - Text strings from EPROM "PRGS 1/2" dump04:15 - Text strings from one EEPROM X28HC25604:20 - Second board teardown05:24 - Third board teardown (UPP20)07:19 - Front assembly08:56 - DC-DC converter
LDM #357: EPR indicator from A300-600 Airbus Simulator Le labo de Michel 2024-01-24 | This video shows the teardown, the reverse engineering and test of an EPR indicator used in a simulator for an airliner Airbus A300-600.00:00 - Intro01:24 - Teardown - Electromechanical assembly03:48 - Electronic boards08:24 - Schematic diagram from reverse engineering09:31 - EPR testAbout EPR:https://skybrary.aero/articles/engine-pressure-ratio-epr
LDM #356: Teardown of two Russian missile sensors Le labo de Michel 2023-12-29 | This video shows the teardown of two Russian sensors. The first sensor is not a part of an Iskander missile but of a X-101 missile.00:00 - Intro00:25 - Optical sensor from X-101 missile02:30 - 3-axis Fiber Optic Gyroscope (probably from Tornado MLRS)LinksA picture of the first sensor with the optics:photo.unian.info/photo/1173510-optiko-elektronnaya-sistema-korrekcii-starogo-obrazca-rakety-h-101Several viewers have found the technical documentation of the Fiber Optic Gyro:http://www.optolink.ru/documents/trs-500_RU.pdfOther information concerning the FOG:en.defence-ua.com/industries/the_life_of_american_astronaut_depends_on_the_intel_chip_from_aliexpress_used_in_russian_rocket_for_tornado_s_mlrs-6320.htmlTechnical documentation in russian:https://ela.kpi.ua/bitstream/123456789/30573/1/Stranskyi_magistr.pdf
LDM #355: Javelin Missile guidance computer - Part 2: answers (in French with subtitles) Le labo de Michel 2023-12-07 | On this video I try to give some answers to some questions regarding the previous video.00:00 - Intro01:14 - My French accent03:13 - Nice boards04:03 - Is it legal to post this on YT ?05:01 - SRAM dump ?06:24 - Powering-on the boards ?06:42 - Is it legal to own that thing ?07:06 - Sensor07:56 - ITAR09:16 - Prototype ?09:48 - Vias09:59 - Power op-amps and fins controlrecorded 2023/12/02
LDM #354: Javelin Missile guidance computer - Part 1: teardown Le labo de Michel 2023-12-01 | This video shows the teardown of the guidance section of a Javelin missile FGM-148.Nota 2023/12/24: this video is intended to show the technology now obsolete used in the 80s-90s on military devices. Similar technology can be found in avionics for instance. On that guidance section there is nothing sensitive, it is just a complex CPU board with golden parts. 00:00 - Intro04:09 - Teardown06:28 - Electronic assembly10:18 - SensorLinks:TOW Missile:youtu.be/s7-6hgX7-zQyoutu.be/5wKB3bmq1fMMaverick Missile Seeker:youtu.be/7dBfYFNp7CMyoutu.be/aCOK3-KvMoE
LDM #353: Radar Tuner TN-131/APR-9 Le labo de Michel 2023-11-27 | This video shows the teardown and reverse engineering of a vintage Radar Tuner TN-131/APR-9.00:00 - Intro01:00 - Teardown02:08 - Input filter06:08 - FI preamplifier08:00 - Mixer10:48 - Servo control feedback potentiometer and reflector voltage setting13:52 - Motor15:38 - Frequency setting test16:34 - Schematic diagramTechnical description:It uses a 1N26 mixer diode and a 2K48 reflex klystron for the local oscillator. Frequency setting uses a DC motor and several devices linked to the output shaft:* A fixed cam permits to modify the frequency of the reflex klystron.* An adjustable cam permits to change the central frequency of the input filter* A potentiometer permits to change the reflector voltage of the klystron according to the frequency* Another potentiometer is connected to the connector, probably for the servo control of the frequency setting mechanism.* A synchro transmitter* An internal indication of the frequency using coding wheelsLinks:Klystron 2K48:http://lampes-et-tubes.info/mwkl/2K48.pdfRecorded 2023/10/31
LDM #352: Sperry Mach/Air Speed indicator Le labo de Michel 2023-11-23 | This video shows the teardown of a Sperry Mach/Indicated Air Speed Indicated ref 2594466-906.00:00 - Intro01:53 - Electro-mechanical assembly04:13 - Electronic assembly
LDM #351:Astek Division Altitude Alert Indicator Le labo de Michel 2023-11-16 | This long video shows the teardown, reverse engineering and test of an Altitude Alert Indicator manufactured by Astek Division in the 70s.The first part of this video shows the teardown followed by the test of this instrument.The second part is more theoretical, the general functioning of this unit is explained as well as some particular topics. 00:00 - Intro00:40 - Teardown01:11 - Electro-mechanical assembly07:22 - Electronic assembly10:37 - Test15:52 - Air Data Computer ARINC565 Dual Speed Synchro18:32 - Altitude Alert - General functionning24:48 - Synchro, resolver, transolver and differential resolver33:33 - Coarse window generation36:48 - Synchro transmitter presence detection38:30 - Detailed schematic from reverse enginneringRecorded 2023/10/23
LDM #350: TRT Radio Altimeter - Teardown, reverse engineering and test Le labo de Michel 2023-11-09 | This video shows the teardown, the reverse engineering and the test of a radio altimeter TRT AHV.5-221 which was used in A300 aircraft.00:00 - Intro01:05 - Teardown06:03 - Non-linear scale08:21 - Tests09:34 - ARINC 55211:00 - Reverse Engineering Part 1: Main circuits14:11 - Reverse Engineering Part 2: Flag circuits and power supply15:40 - Reverse Engineering Part 3: Decision Height circuitsTechnical detailsThis Radio Altimeter is compliant with ARINC 552 standard.The servo control loop uses a potentiometer for the feedback and a DC motor for the drive of the tape. The input is a differential DC voltage. The error voltage (feedback voltage - input voltage) is fed to the servo amplifier. The servo amplifier has a special feedback which permits to compensate partially the series resistance of the DC motor. This permits to have a control of the speed of the motor which permits a damping of the control loop.Connector pinout:A-B: 26Vac 400HzL : signal groundY : signal input (+)Z : signal input (-)a-L : Test push buttonD-g : 5V lightinge-f : relay contact for decision height (closed when the altitude is below the DH)Useful links:Burr-Brown document: Control a DC Motor without Tachometer Feedbackti.com/lit/an/sboa043/sboa043.pdf
LDM #349: Blackburn Buccaneer height and rate of climb indicator Le labo de Michel 2023-11-05 | This video shows the teardown and test of a Blackburn Buccaneer height and rate of climb indicator KHB0203 manufactured by Smiths.00:00 - Intro01:02 - Teardown05:34 - TestTechnical details:- The vertical speed needle is driven using a synchro receiver- A servo control is used for the altitude. One complete revolution of the synchro corresponds to approximately 25,000 feet.- Not shown on the video: the triangular screw one can see on the bottom of the front panel permits to adjust the zero altitude by rotating the body of the synchro control transformer used for the servo control.- The solenoid used for the flag seems activated by a motorized potentiometer. I didn't test this feature.
LDM #348: teardown and test of a Kollsman Servo Altimeter Le labo de Michel 2023-10-31 | 00:00 - Intro02:22 - ARINC 465 Standard02:40 - Dual speed synchro03:58 - Teardown05:33 - Test07:49 - Flag circuits08:29 - Flag test
LDM #347: DC-10 Clock - Teardown, reverse engineering and test Le labo de Michel 2023-10-25 | 00:00 - Intro00:56 - Teardown02:34 - Reverse Engineering Part 1: Stepper motor driver04:39 - Reverse Engineering Part 2: Power supply05:30 - 60Hz quadrature generator board06:30 - quadrature generator board test06:39 - Final design and test
LDM #346: HSI Collins 331A-8K - Part 1: Teardown and first tests Le labo de Michel 2023-10-20 | This video shows the teardown and partial test of an Horizontal Situation Indicator (HSI) which was used in BAE-146 Aircraft.00:00 - Intro01:19 - Teardown10:08 - Test
LDM #345: Cessna dual engine RPM % indicator - Teardown, reverse engineering and test Le labo de Michel 2023-10-14 | This video shows the teardown, the reverse engineering, the repair and the test of a vintage Cessna dual turbine RPM indicator.00:00 - Intro00:37 - Teardown03:04 - Preparation for reverse engineering04:17 - Reverse engineering part 1: power supply05:33 - Reverse engineering part 2: main circuits07:20 - Issue #1: wrong transistor orientation09:15 - Issue #2: cracked solder joint10:11 - TestNote about the construction: the electronic side of this indicator was poorly constructed. The dual layer non-plated through hole PCB without solder mask nor conformal coating has resulted in a solder joint crack. Someone attempted to repair this instrument (maybe because of this issue) and one 4-pins Darlington transistor was not fitted correctly during this repair.Internal circuits: the input signal is fed to a comparator which delivers a square wave signal. This signal is fed to a discrete monostable which delivers a rectangular signal. The duty cycle and therefore the mean value is proportional to the input frequency. After filtering the DC voltage created is used as the input of a servo control loop. The feedback device is a potentiometer. A chopper using two dual emitter pnp chopper transistors converts the DC error voltage into an AC error voltage which is fed to the servo amplifier which drives the AC motor.This instrument incorporates an inverter for each channel for the generation of the AC voltage required by the motor.The use of an AC motor and the choice of a DC power supply voltage complicate dramatically the circuits of this instrument.Particular parts used:Dual emitter PNP chopper transistor: Sprague 460070-2Servo amplifier power stage and inverter: Darlington U2T101Pinout from reverse engineering:(x): left engineA (K): input signal (5Vpp min, positive signal), 70Hz for 100%B (F): common line for power supply and inputC (E): positive power supply (14 or 28V, automatic selection by the unit)About bipolar chopper transistors and circuits:http://www.bitsavers.org/components/motorola/_appNotes/AN-0470_Bipolar_Chopper_Transistors_And_Circuits.pdfRecorded 2023/07/23
LDM #344: Intertechnique Fuel Quantity Indicator - Teardown, reverse engineering and test Le labo de Michel 2023-10-10 | This video shows the teardown, the reverse engineering and the test of a digital fuel quantity indicator manufactured by Intertechnique.fr.wikipedia.org/wiki/Intertechnique00:00 - Intro00:55 - teardown03:36 - Reverse engineering part 1: power supply04:49 - Reverse engineering part 2: dimmer circuits06:13 - Reverse engineering part 3: analog board07:04 - TestConnector pinout:A: groundB: negative power supply -20VC: positive power supply +20VD: input voltage (1 to 5V with 5V reference voltage)E: reference voltage inputF: groundH: 82 ohms to EJ: digital ground (connected to analog ground through two diodes back to back)T-U: lighting (0 to 5Vrms 400Hz)Technical description:- The input voltage is fed to a 10-bits ADC made with a 4040 counter, one 10-bits DAC, two comparators and one JK flip-flop.- The 5V power is an SMPS which uses a classic SG1524 configured as a step-down DC-DC converter.- Display value is 0 for 1V input voltage and 5V reference voltage- Display value is 9900 for an input voltage equals to the voltage reference- The rightmost digit is always 0, fuel quantity displayed is XXX0 pounds- This instrument requires two power supply voltages: +20V and -20V. - There is a dimmer circuit which permits to attenuate the display luminosity according to the level of the lighting voltage.- The refresh rate is approximately 2 seconds.- The display is blank if the reference voltage is below 2V- The display is blinking if the lighting voltage is not present
LDM #343: Columbia Servo Accelerometer Le labo de Michel 2023-10-04 | 00:00 - Intro00:35 - Teardown01:45 - How it works01:52 - Reverse engineering03:31 - Repairing the coil04:03 - Open loop test04:53 - Closed loop testLinks:LDM #169: Aircraft Servo Potentiometer Type 6A/4725 Teardown and Testsyoutu.be/_i8dZ0o0ZIs
LDM #342: Blackburn Buccaneer Gyro Reference Unit Le labo de Michel 2023-09-29 | 00:00 - Intro03:28 - Roll stabilization mecanism05:35 - Pressure switch06:52 - Internal assembly07:50 - Gyro unit09:39 - Rotorace gyro11:05 - Gyro11:30 - TestLDM #349: Blackburn Buccaneer height and rate of climb indicator (beginning from 2023/11/17)youtu.be/4Fg5cnIGl-U
LDM #341: Indicator N2 Tachometer - Teardown, reverse engineering and test Le labo de Michel 2023-09-25 | 00:00 - Intro00:50 - Teardown04:47 - Torquer test05:55 - Reverse engineering part 1: frequency to voltage converter08:27 - Reverse engineering part 2: amplifiers09:16 - Reverse engineering part 3: servo amplifier10:05 - Test12:02 - Charge balance frequency to voltage converter - comment ça marche ?17:20 - Comparison with actual measurements
LDM #340: C-5 Galaxy EPR Indicator - Teardown and test Le labo de Michel 2023-09-21 | 00:00 - Intro00:30 - Servo amplifiers module01:53 - Figuring out the pinout02:57 - Test04:21 - Opening the instrument07:15 - What's inside the electro-mechanical assemblyExamples of EPR transducers:youtu.be/QlEehvyJ-M4youtu.be/kMyuKtHlHiAyoutu.be/KMIZj74kBrYOther EPR indicators:youtu.be/WhxyEzI6IF0youtu.be/tN16HeZ750cyoutu.be/Dlsc9dlFBGI
LDM #339: Smiths Distance Miles Indicator - Teardown and test Le labo de Michel 2023-09-14 | This video shows the teardown and test of a distance miles indicator manufactured by Smiths. At the end a quick reverse engineering is performed for the input connections.This instrument requires an external AC voltage reference voltage for the feedback potentiometer (out of phase regarding input signal). This permits to have a display which doesn't depend on the instrument itself.00:00 - Intro01:54 - In search for power supply pins04:48 - In search for input pin05:47 - In search for flag pins06:11 - In search for ground pin07:34 - Preliminary test (open loop)08:33 - Final test (closed loop)Pinout:A-B : Power Supply input 26Vac 400HzC : input commonD(-) E(+) : flag (28Vdc)F-G : feedback potentiometer (2k)H : input
LDM #338: Air Nautical Miles Indicator - Teardown, reverse engineering and test Le labo de Michel 2023-09-08 | This video shows the teardown, the detailed schematic diagrams and the test of a vintage Elliott Air Nautical Miles Indicator manufactured in the late 60s.The input is a negative DC voltage. The miles result is shown using a mechanical display activated by a stepper motor. The more negative the input voltage, the faster the counter advances.The input voltage is fed to a VCO. The VCO generates a pulse signal with a frequency proportional to the negative input voltage. This clock signal is fed to the stepper motor driver circuits.This indicator uses several smd DTL logic ICs and two op-amps for the VCO.00:00 - Intro00:34 - Teardown01:37 - Electronic boards04:11 - Reverse engineering - VCO circuits05:13 - Reverse engineering - Stepper motor control06:23 - TestOp-amps (X2): SN524AT flip-flop (X2): 994551 = MC945Fquad NAND gate (1X): D946Connector pinout:A: -6.4V reference voltage outputB: input voltage (must be negative)C: common for input voltageJ-K: 5V for lightingG-H: 26Vac 400Hz power supply
LDM #337: RAF Avro Vulcain Electrical Indicator Type 101 - Part 2: Reverse Engineering and test Le labo de Michel 2023-09-05 | This video shows the reverse engineering and test of a vintage RAF Avro Vulcain. The teardown was shown in previous video:youtu.be/cpOrcHsgwJY00:00 - Reverse Engineering02:35 - Test03:41 - Radar frequency estimationPart 1:LDM #336: RAF Avro Vulcain Electrical Indicator Type 101 - Part 1: teardownyoutu.be/cpOrcHsgwJY
LDM #336: RAF Avro Vulcain Electrical Indicator Type 101 - Part 1: teardown Le labo de Michel 2023-08-30 | This video shows the teardown of a vintage RAF Avro Vulcain Electrical Indicator Type 101 used for the Doppler radar system. It contains an air speed indicator, a drift indicator, a distance miles indicator, and a ground speed indicator using a bar graph.This indicator uses plenty of sub-miniature and ultra-miniature vacuum tubes.00:00 - Intro01:20 - Teardown03:21 - First power up04:36 - Filters box05:31 - Indicators08:05 - Indicator repairPart 2 (on line 2023/09/05):LDM #337: RAF Avro Vulcain Electrical Indicator Type 101 - Part 2: Reverse Engineering and testyoutu.be/TJI_owLNPZgrecorded 2023/08/04
LDM #335: Turbine Gas Temperature Indicator - Teardown, repair and test Le labo de Michel 2023-08-25 | 00:00 - Intro01:20 - Teardown01:50 - Desoldered capacitor03:52 - First test05:15 - Repair06:30 - Quick test with a solder iron07:06 - Final test using a thermocouple simulatorThis video shows the teardown, the repair and test of a Turbine Gas Temperature Indicator manufactured in 1986 by Intercontinental Dynamics.The power supply and the needle command circuits are identical to the ones of the RPM indicator described in video #97:youtu.be/aOXe8n5juoMThe input is a K thermocouple. Cold junction is present on the front-end board using 2 massive copper pieces. The voltage is amplified using two op-amps OP41 and converted into a digital data using a Teledyne 3-1/2 digit ADC TSC8750 with BCD outputs. This digital data is displayed on three 7-segments displays using three classic BCD to 7-segments drivers CD4511.This digital value is also fed to the addresses of two EPROMs. The EPROMs contains sine and cosine tables which drive two 8-bits DACs DAC0800. Each DAC output is fed to a power op-amp LH0021K which drive a sine-cosine DC synchro which sets the needle.alldatasheet.com/datasheet-pdf/pdf/98591/NSC/LH0021K.htmlPin-out of the rear connector:G: 0VF: 26VAC 400 HzE-D: lightingA-C: K thermocouple inputRecorded 2023/07/29
LDM #334: Static Inverter PS285: reverse engineering and modification for 3-phases inverter. Le labo de Michel 2023-08-17 | This video shows the reverse engineering of the PS285 inverter. After understanding how this inverter works I show a simple method to synchronize the output signal to another inverter. Finally the video shows the new inverter which delivers two AC signals at 400Hz with 0 or 120° phase shift using two PS285 inverters.00:00 - Intro00:47 - Reverse Engineering Part 1: 400Hz sine oscillator03:11 - Reverse Engineering Part 2: Output stage04:02 - Reverse Engineering Part 3: Output voltage control circuits05:16 - Modification for slave mode operation06:08 - Slave Mode Test07:38 - Modification for slave mode08:28 - Phase shifter and final design09:49 - TestLink to part 1:LDM #323: Aircraft Static Inverter EMP Electronics PS285: teardown and testyoutu.be/2xIdZvDX5XA
LDM #333: teardown and test of a Smiths Radio Magnetic Indicator Le labo de Michel 2023-08-12 | This video shows the teardown and test of a Radio Magnetic Indicator (RMI) ref WL/107 manufactured by Smiths. 00:00 - Intro00:41 - Teardown01:49 - Searching for the pinout03:22 - Test
LDM #332: Static Air Temperature Indicator KOLLSMAN INSTRUMENTS Le labo de Michel 2023-08-06 | This video shows the teardown, the reverse engineering and the test of a Static Air Temperature Indicator Type C 25725 10 001 manufactured by Kollsman Instruments in 1980.This indicator uses a magnetic amplifier with two transistors for the servo control of the needle.00:00 - Intro00:15 - Teardown03:03 - Reverse engineering04:31 - Test
