Very nice teardown, as always. Thanks for all of your hard work! The boards were of an early 80s design and surface mount stuff had not yet taken off. That's what makes this era of technology so interesting. You can actually SEE every component without a microscope. And I remember having to deal with the chromal/alumal wiring coming from each engine sensor up to the cockpit. Every connector between the thermocouples and indicator had to maintain the chromal/alumal wiring with special pins, just like you pointed out. The flight data recorder, wired in parallel with the indicator, had a high enough impedance to not affect the circuit. As you know, the Type K thermocouple generates just a tiny voltage when temperatures changes. And, as always, the LCDs are failing on this indicator. It doesn't seem to matter who the manufacturer is, or what country its made in, when it comes to washed-out, stained or faded LCDs. I've seen them on radio control heads, instruments, autopilot mode select panels, clocks and other cockpit devices all failing in one way or another. They just can't seem to tolerate direct sunlight and somehow degrade over time. I know avionics manufacturers spend millions of dollars on testing and trying to improve LCD reliability, but I have not seen anyone truly fix the problems. You would think that they would have it figured out by now. But what I saw on this teardown instrument are the same flaws I see in current production equipment. Have to seen the same LCD failures in your other teardowns?
Beautifully made! But for what it does this seems like a surprisingly large amount of hardware, especially considering that this device does contain microprocessors. It is also interesting that the bimetallic thermocouple cable comes from the engine all the way into cockpit, instead of the signal being digitized somewhere closer to the source.
It is still a common practice in industrial instrumentation! We're operating 20-30 years behind the curve but we're slowly getting there. Note that the device contains a microprocessor, but not a microcontroller in the modern sense. They needed a lot of supporting hardware, and hardly anything was integrated into them.
This part is robbed from Boeing 757 or 767. You have four indication windows for TWO engines only. The color of panel similar to B747-400, but they don't have such indicators. Even as an option.
*Boeing 757 Standby Engine Instrument Teardown and Reverse Engineering* * *General:* The video showcases a teardown and analysis of a General Electric S231n001 Standby Engine Instrument from a Boeing 757, manufactured in 1986. * *Instrument Functionality:* The instrument displays four key engine parameters: EPR (Engine Pressure Ratio), N1 (Low-Pressure Turbine Speed), EGT (Engine Gas Temperature), and N2 (High-Pressure Turbine Speed) for both left and right engines. * *Internal Design:* The instrument features two identical and independent circuits, one for each engine, including separate power supplies. * *EGT Measurement (Thermocouple):* * Utilizes an Intersil AD571 10-bit ADC for digitization. * Employs a cold junction compensation mechanism within the instrument for accurate temperature readings. * Features a dynamic measurement rate adjustment based on the rate of temperature change, ranging from 1 Hz to 30 Hz. * *EPR Measurement (Digital):* * Relies on a RCA CDP1802 COSMAC microprocessor and an EPROM for processing. * Likely uses an ARINC 429 interface for data communication. * *N1 and N2 Measurement (Frequency-Based):* * Both N1 and N2 boards employ a Phase-Locked Loop (PLL) to multiply the input frequency by a factor of 220. * They share a similar design to the EGT board, including a dynamic measurement rate adjustment based on the rate of frequency change. * *Power Supply:* * Employs a pulse-width modulation (PWM) controller (1524J) for voltage regulation. * Provides isolated power supplies for each of the measurement circuits. * *Display:* The instrument uses LCD displays for readout, which are known to be susceptible to degradation over time, especially with exposure to sunlight. * *Self-Test Functionality:* The instrument includes a built-in self-test capability. * *Notable Components:* The instrument utilizes a mix of through-hole components common for its era, including op-amps (LM158, OP05H, 747), logic ICs (various CD4000 series), and a 555 timer. * *Observations:* * The video creator highlights the instrument's robust and well-organized construction. * Some minor modifications and "bodges" on the circuit boards suggest potential troubleshooting or adjustments made during its service life. I used gemini-1.5-pro-exp-0801 to summarize the transcript. Cost (if I didn't use the free tier): $0.06 Input tokens: 16528 Output tokens: 577
Very interesting that it runs on a COSMAC CDP1802! Thank you for your fascinating videos and cheers from the Colorado Rocky Mountains.
Very nice teardown, as always. Thanks for all of your hard work! The boards were of an early 80s design and surface mount stuff had not yet taken off. That's what makes this era of technology so interesting. You can actually SEE every component without a microscope. And I remember having to deal with the chromal/alumal wiring coming from each engine sensor up to the cockpit. Every connector between the thermocouples and indicator had to maintain the chromal/alumal wiring with special pins, just like you pointed out. The flight data recorder, wired in parallel with the indicator, had a high enough impedance to not affect the circuit. As you know, the Type K thermocouple generates just a tiny voltage when temperatures changes. And, as always, the LCDs are failing on this indicator. It doesn't seem to matter who the manufacturer is, or what country its made in, when it comes to washed-out, stained or faded LCDs. I've seen them on radio control heads, instruments, autopilot mode select panels, clocks and other cockpit devices all failing in one way or another. They just can't seem to tolerate direct sunlight and somehow degrade over time. I know avionics manufacturers spend millions of dollars on testing and trying to improve LCD reliability, but I have not seen anyone truly fix the problems. You would think that they would have it figured out by now. But what I saw on this teardown instrument are the same flaws I see in current production equipment. Have to seen the same LCD failures in your other teardowns?
Beautifully made! But for what it does this seems like a surprisingly large amount of hardware, especially considering that this device does contain microprocessors.
It is also interesting that the bimetallic thermocouple cable comes from the engine all the way into cockpit, instead of the signal being digitized somewhere closer to the source.
It is still a common practice in industrial instrumentation! We're operating 20-30 years behind the curve but we're slowly getting there. Note that the device contains a microprocessor, but not a microcontroller in the modern sense. They needed a lot of supporting hardware, and hardly anything was integrated into them.
Bonjour, avez vous déjà pensé de faire un teardown d'un HUD ou même un Gyro Gunsight ? Ça pourrait être très intéressant! Super vidéo comme toujours.
Amazing.
Lots of support from Pakistan
This part is robbed from Boeing 757 or 767. You have four indication windows for TWO engines only. The color of panel similar to B747-400, but they don't have such indicators. Even as an option.
It says "FOR PW-2037 ENGINE" on the side so 757 probably.
Qual o ano de fabricação? 1985
1986/ 05
@@Hooligan.Residuato.Italia.90 muito obrigado pela resposta amigo
*Boeing 757 Standby Engine Instrument Teardown and Reverse Engineering*
* *General:* The video showcases a teardown and analysis of a General Electric S231n001 Standby Engine Instrument from a Boeing 757, manufactured in 1986.
* *Instrument Functionality:* The instrument displays four key engine parameters: EPR (Engine Pressure Ratio), N1 (Low-Pressure Turbine Speed), EGT (Engine Gas Temperature), and N2 (High-Pressure Turbine Speed) for both left and right engines.
* *Internal Design:* The instrument features two identical and independent circuits, one for each engine, including separate power supplies.
* *EGT Measurement (Thermocouple):*
* Utilizes an Intersil AD571 10-bit ADC for digitization.
* Employs a cold junction compensation mechanism within the instrument for accurate temperature readings.
* Features a dynamic measurement rate adjustment based on the rate of temperature change, ranging from 1 Hz to 30 Hz.
* *EPR Measurement (Digital):*
* Relies on a RCA CDP1802 COSMAC microprocessor and an EPROM for processing.
* Likely uses an ARINC 429 interface for data communication.
* *N1 and N2 Measurement (Frequency-Based):*
* Both N1 and N2 boards employ a Phase-Locked Loop (PLL) to multiply the input frequency by a factor of 220.
* They share a similar design to the EGT board, including a dynamic measurement rate adjustment based on the rate of frequency change.
* *Power Supply:*
* Employs a pulse-width modulation (PWM) controller (1524J) for voltage regulation.
* Provides isolated power supplies for each of the measurement circuits.
* *Display:* The instrument uses LCD displays for readout, which are known to be susceptible to degradation over time, especially with exposure to sunlight.
* *Self-Test Functionality:* The instrument includes a built-in self-test capability.
* *Notable Components:* The instrument utilizes a mix of through-hole components common for its era, including op-amps (LM158, OP05H, 747), logic ICs (various CD4000 series), and a 555 timer.
* *Observations:*
* The video creator highlights the instrument's robust and well-organized construction.
* Some minor modifications and "bodges" on the circuit boards suggest potential troubleshooting or adjustments made during its service life.
I used gemini-1.5-pro-exp-0801 to summarize the transcript.
Cost (if I didn't use the free tier): $0.06
Input tokens: 16528
Output tokens: 577