IBM System/360 Front Panel CuriousMarc 2017-02-01 | I recently acquired this front panel from an IBM 360 mod 50, with lots of switches and over 250 blinkenlights. The IBM System/360 was an iconic mainframe computer introduced in 1964 (see promotional video here: youtu.be/V4kyTg9Cw8g). The system was a huge development gamble for IBM, with all the "models" from small to huge sharing mostly the same overall architecture and instruction set, but with radically different hardware implementations depending on the cost and performance point. A key novelty was the introduction of "SLT" ceramic hybrid modules, pre-dating the integrated circuit, but with denser packaging than individual transistors. This front panel is from a model 50 (in IBM speak a "mod 50"), a larger business system. And yes, I'll take you through most of the buttons. Take this with a grain of salt, this is very complicated and I am new at it. Understanding the meaning of every one of the 1,152 bits that the lights and rollers can display will take some serious further study. I am sure the IBM CEs (Customer Engineers) that spent their careers on these panels will chime in the comments section and correct all my mistakes.Try Ken Shirriff's emulation of a running 360 driving this panel:static.righto.com/360Ken Shirriff's article about the 360:righto.com/2022/01/ibm360model50.htmlChapters00:00 Panel unboxing00:53 First look, front side02:28 First look, back side04:17 Repairs06:52 Every part of the panel explained!07:43 Power panel09:00 Memory panel 09:49 Emergency pull10:11 Auxilaliary memory power panel11:05 Channel test panel11:34 Main indicator panel 12:47 Data and address entry panel14:21 Error lights panel15:41 Debug / program flow control switches17:51 Time counters18:22 Manual operation and debug panel20:50 FLT control (firmware test routines) panel21:51 Start/boot (IPL) panel23:02 Overall view, flipping rollers, future workOur sponsor for PCBs: pcbway.comSupport the team on Patreon: patreon.com/curiousmarcMerch on Teespring: teespring.com/stores/curiousmarcs-storeLearn more on companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Apollo Comms Part 34: Trying every function of the Apollo command system CuriousMarc 2024-10-08 | We finally have our Apollo command system all working! Let's understand and try every function so we can hack the Apollo spacecraft the next time they launch it...Apollo Comms Playlist: youtube.com/watch?v=v49ucdZcx9s&list=PL-_93BVApb58SXL-BCv4rVHL-8GuC2WGbLinks to doc:curiousmarc.com/space/apollo-s-band-communicationsvirtualagc.github.io/virtualagc/QuestForInfo.htmlibiblio.org/apolloibiblio.org/apollo/Documents/HSI-481260.pdfElevator Music Credit: Crinoline Dreams by Kevin MacLeodStuff that supports the channel:- Support us on Patreon: patreon.com/curiousmarc- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-storeOur sponsors- PCBWay: fast turn PCBs, pcbway.com- ElectroRent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.com
Cape Canaveral Historic Launch Sites Visit CuriousMarc 2024-09-01 | Thanks to Carl and the Cape Canaveral Space Force Museum, we get a very special visit of the cape's historic launch sites, and relive the pioneering days of the Space Race. The launch of Explorer 1 (NASA documentary): youtube.com/watch?v=NfMIrKkzRx8Biography of a Missile (CBS documentary on Explorer 7X ending with Juno II failure): youtube.com/watch?v=o8T8UPtw9l0&t=3155sFirst Atlas launch: youtube.com/watch?v=q_ksxx_qXNcNASA 1963 Gemini Documentary "All Systems Go": youtube.com/watch?v=9AokEeaSGwYStuff that supports the channel:- Support us on Patreon: patreon.com/curiousmarc- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-storeOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Modern Fails: Newall C80 DRO repair CuriousMarc 2024-08-20 | My expensive lathe digital readout just failed, and Newall does not want to repair it! So, we reverse engineer it, and find out that the proprietary principle of operation is absolutely genius, involving ball bearings and magnetics, with a readout precision of better than 10 microns. And the fault is quite unexpected. Hint: not a capacitor.Stuff that supports the channel:- Support us on Patreon: patreon.com/curiousmarc- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Apollo Comms Part 33: Is there something wrong with our NASA Up Data Link transmitter? CuriousMarc 2024-07-26 | In the last episode, we managed to send Up Data commands using a PSK transmitter made up of HP equipment. But we were unsuccessful when using our original NASA UDL transmitter. Is there still something wrong with it?Apollo Comms Playlist: youtube.com/watch?v=v49ucdZcx9s&list=PL-_93BVApb58SXL-BCv4rVHL-8GuC2WGbLinks to doc:curiousmarc.com/space/apollo-s-band-communicationsvirtualagc.github.io/virtualagc/QuestForInfo.htmlibiblio.org/apolloibiblio.org/apollo/Documents/HSI-481260.pdfElevator Music Credit: Crinoline Dreams by Kevin MacLeodStuff that supports the channel:- Support us on Patreon: patreon.com/curiousmarc- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-storeOur sponsors- PCBWay: fast turn PCBs, pcbway.com- ElectroRent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.com
HP 7044A X-Y Recorder Restoration CuriousMarc 2024-07-20 | It takes another long video full of analog goodness to repair this X-Y recorder beauty, because we end up fixing it twice! We also rejuvenate the pens while we are at it, also using two different methods.HP 7044B and 7045B Service Manual: archive.org/details/hp-7044-b-7045-b-x-y-recorder-operations-and-service-manual-07044-90006-nov.-1980Stuff that supports the channel:- Support us on Patreon: patreon.com/curiousmarc- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 Intro, previous HP 7035B restoration01:06 Inspection and first try02:42 Disassembly, slide cleaning and platen repair06:44 A power supply fault?08:44 X-axis fix09:30 Y power supply debug and fix13:07 Y-axis still fails!13:42 Servo circuits (with elevator music)18:18 Y servo circuit debug21:01 It self heals, then self breaks!22:10 Bad op-amp?24:55 Root cause, repair, and calibration28:28 Restoring the pens32:24 It breaks again! 34:02 Second repair37:59 Laser L-I curve plot demo
Visiting the Computer Museum of America CuriousMarc 2024-07-15 | After VCF East, we were invited for a very special visit of the Computer Museum of America, near Atlanta, Georgia. Comes with us for a tour!Stuff that supports the channel:- Support us on Patreon: patreon.com/curiousmarc- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Apollo Comms Part 32: Breaking the Updata Link Code CuriousMarc 2024-07-12 | We finally crack the Apollo uplink subbit code. And as any good hacker would do, we immediately try to send an abort command to the spacecraft.Apollo Comms Playlist: youtube.com/watch?v=v49ucdZcx9s&list=PL-_93BVApb58SXL-BCv4rVHL-8GuC2WGbLinks to doc:curiousmarc.com/space/apollo-s-band-communicationsvirtualagc.github.io/virtualagc/QuestForInfo.htmlibiblio.org/apolloibiblio.org/apollo/Documents/HSI-481260.pdfElevator Music Credit: Crinoline Dreams by Kevin MacLeodStuff that supports the channel:- Support us on Patreon: patreon.com/curiousmarc- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-storeOur sponsors- PCBWay: fast turn PCBs, pcbway.com- ElectroRent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.com
1962 Japanese 9-Transistor Radio CuriousMarc 2024-07-11 | In this mini video we fix up and admire an early Japanese 9-transistor AM-FM radio, which must have felt like a wonder of miniaturization at the time. It was OEM'ed under dozens of different brand names around the world. Many thanks to Jeri Ellsworth for donating this unit.Stuff that supports the channel:- Support us on Patreon: patreon.com/curiousmarc- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-storeOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Apollo Comms Part 31: UDL Grand Opening and Power Up CuriousMarc 2024-06-25 | We open up the Up Data Link box, which was the remote control box for the spaceship, and power it up for the first time. Many thanks to Hirox: hirox-usa.comApollo Comms Playlist: youtube.com/watch?v=v49ucdZcx9s&list=PL-_93BVApb58SXL-BCv4rVHL-8GuC2WGbLinks to doc:curiousmarc.com/space/apollo-s-band-communicationsvirtualagc.github.io/virtualagc/QuestForInfo.htmlibiblio.org/apolloibiblio.org/apollo/Documents/HSI-481260.pdfElevator Music Credit: Crinoline Dreams by Kevin MacLeodStuff that supports the channel:- Support us on Patreon: patreon.com/curiousmarc- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-storeOur sponsors- PCBWay: fast turn PCBs, pcbway.com- ElectroRent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.com
Donated Eskalab Spectrophotometer CuriousMarc 2024-06-16 | We got a free spectrophotometer lab instrument from the 1960s! It is a wounded beauty: it's devoid of any online information, is missing tubes, and one of the boards says "BAD" on it. Can we save it?Stuff that supports the channel:- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Oscars new PDP-10 replica (and PDP-8 and PDP-11 too) CuriousMarc 2024-05-31 | Oscar Vermeulen is well-known for his highly accurate, ⅔ scale replicas of DEC's popular PDP computers. Here he shows off the newest member of the family, the PiDP-10, which gets us to retrace the history of MIT's AI lab and the Incompatible Timesharing System.Get a PiDP-10: obsolescence.wixsite.com/obsolescence/pidp-10-get-oneGet Steven Levy's Hackers book: amzn.to/4bIVz5wPiDP-10: obsolescence.wixsite.com/obsolescence/pidp10PiDP-8: obsolescence.wixsite.com/obsolescence/pidp-8PiDP-11: obsolescence.wixsite.com/obsolescence/pidp-11Oscar's website: obsolescence.wixsite.com/obsolescenceITS reconstruction project: https://obsolescence.dev/its.htmlLars Brinkhoff ITS GitHub: github.com/PDP-10/itsPDP-1 video: youtu.be/1EWQYAfuMYwStuff that supports the channel:- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Apollo Comms Part 30: We explain and debug modern (CD4046B) and vintage (Apollo) PLL circuits. CuriousMarc 2024-05-11 | We build a Phase Locked Loop (PLL) FM demodulator for extracting the Apollo downvoice from its subcarrier, using the classic 7046B IC. But in the meantime, as luck would have it, NASA's own S-band receiver's PLL seems to have gone bonkers, and we can't lock to the spacecraft microwave downlink anymore! So we'll get very hands on with PLLs in this episode. Expect a healthy dose of PLL elevator music.Apollo Comms Playlist: youtube.com/watch?v=v49ucdZcx9s&list=PL-_93BVApb58SXL-BCv4rVHL-8GuC2WGbOlder video on Fractional-N PLLs, used for frequency synthesis: youtube.com/watch?v=z-50pSc_wg8Links to doc:curiousmarc.com/space/apollo-s-band-communicationsvirtualagc.github.io/virtualagc/QuestForInfo.htmlibiblio.org/apolloibiblio.org/apollo/Documents/HSI-481260.pdfStuff that supports the channel:- Support us on Patreon: patreon.com/curiousmarc- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store- Contact info: youtube.com/curiousmarc/aboutElevator Music Credit: Crinoline Dreams by Kevin MacLeodOur sponsors- PCBWay: fast turn PCBs, pcbway.com- ElectroRent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.com
May the 4th Vintage Hack #retro #computer #starwars #maythe4thbewithyou CuriousMarc 2024-05-06 | Oh no, I'm one day late! Hopefully it still counts. Original full length video from 2019 here: youtu.be/UNdu0YQfvF0
HP 9895A Part 2: Epic Controller Board Repair (and a transparent chip surprise) CuriousMarc 2024-05-03 | We restore more HP 9895A dual 8" diskette HP-IB drives, but these will be way more challenging. We'll need a full on logic analyzer assisted repair to debug a really, really nasty fault. It's a long video, but don't miss the intermission where Master Ken inspects a transparent silicon-on-sapphire chip!Many thanks to HP enthusiast Craig Ruff for the ROM dump and disassembly.8" Floppy Playlist: youtube.com/playlist?list=PL-_93BVApb59tOBmcSGTdc79zuEgp6MxF&si=FWBA4AhHjoQ964ghHP 9825 Playlist: youtube.com/playlist?list=PL-_93BVApb58Hy846J52DT8FeF9USYJUn&si=ubr1GO7EtGn5h8IyKen's Silicon-on-Sapphire chip blog post: http://www.righto.com/2023/12/HP-silicon-on-sapphire-phi-chip.htmlStuff that supports the channel:- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Visiting the System Source Computer Museum CuriousMarc 2024-04-30 | We get a private tour of the System Source Museum near Baltimore, MD. What a gem of a computer museum!Stuff that supports the channel:- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
We attend the Vintage Computer Festival (VCF East 2024) CuriousMarc 2024-04-24 | We had a great time at VCF East, the annual vintage computer exhibit in Wall, New Jersey. Carl was showing off an IBM 1130 he just restored, and we had a round table about the Apollo Guidance Computer restoration. But there is more: the Vintage Computer Federation museum with its working UNIVAC, a military technology museum, and even a prototype AGC! The video of our AGC round table talk is available on the VCF channel: youtube.com/watch?v=4Qx_XqnJtJwStuff that supports the channel:- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Modern Fails: Samsung ML-2525W laser printer double repair: picks up two sheets, does not power on CuriousMarc 2024-04-04 | In the Modern Tech Fails series, we tackle the Samsung ML-2525W laser printer, which fails like all its siblings for stupidly simple reasons.Nice video of the solenoid repair (in Russian!): youtu.be/PM-Lc8DpLFcPrevious video where we tear down a failed Capxon capacitor and a good capacitor: youtu.be/Z4Kp8BDMzHYStuff that supports the channel:- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
We restore the HP 9895 dual 8 diskette to play a Colossal Cave game! (ft. Usagi Electric) CuriousMarc 2024-04-02 | We restore a vintage HP 9895A dual 8" diskette HP-IB drive, and put it to good use by playing the Colossal Cave Adventure on the HP 9825 calculator.8" Floppy Playlist: youtube.com/playlist?list=PL-_93BVApb59tOBmcSGTdc79zuEgp6MxF&si=FWBA4AhHjoQ964ghHP 9825 Playlist: youtube.com/playlist?list=PL-_93BVApb58Hy846J52DT8FeF9USYJUn&si=ubr1GO7EtGn5h8IyStuff that supports the channel:- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Free Abandoned HP 3478A 5-½ Digit DVM Repair CuriousMarc 2024-03-01 | We repair a classic HP 3478A 5-½ digit voltmeter, and admire its ultra complicated A to D converter.HP Multislope II ADC patent: patents.google.com/patent/US4357600A/enIan Scott Johnston video on HP 3457 backlight mod: youtu.be/oEu7nqOkKxoBlacklight display mod: eevblog.com/forum/testgear/another-hp3478a-backlight-display-hackLCD protocol reverse engineering: eevblog.com/forum/projects/led-display-for-hp-3457a-multimeter-i-did-it-)/msg1347268/#msg1347268OLED mod: eevblog.com/forum/testgear/hp3548-hp3457-oled-displayKen Shirriff's Nanoprocessor reverse engineering: http://www.righto.com/2020/09/hp-nanoprocessor-part-ii-reverse.htmlKen Shirriff’s reverse engineering of the hybrid in Marco Reps’ HP 3458: https://x.com/kenshirriff/status/1448392567167479812?s=61&t=UXfboHQEfahjAKeGVe1J8wJeff Peletz amazing HP instrument pictures: http://hparchive.com/wallpaperStuff that supports the channel:- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
F8 Fly-By-Wire System (Apollo Guidance Computer Part 31) CuriousMarc 2024-02-19 | We get a chance to inspect the actual Apollo Guidance System that flew in NASA's F8 Digital Fly-By-Wire experimental plane. We explain how it worked, and recover the software from its core rope memory. The result is a bit of a surprise! Apollo Guidance Computer Restoration Series: youtube.com/playlist?list=PL-_93BVApb59FWrLZfdlisi_x7-Ut_-w7More videos showing some of Steve Jurvetson’s collection:Steve’s collection part 1: youtu.be/3Y-MosGsFMsSteve’s collection part 2: youtu.be/5ZBRw07IbgoSteve’s collection part 3: youtu.be/3Y-MosGsFMsVirtual AGC Github repository:github.com/virtualagc/virtualagcStuff that supports the channel:- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 Summary of previous episodes02:05 The F8 Fly-By-Wire pallet03:43 Why Digital Fly-By-Wire?06:24 NASA Dryden Flight Research Center08:08 NASA's F8 DFBW program14:10 Shuttle support missions15:20 Inspecting the pallet19:05 Apollo SPS engine20:43 Core rope extraction24:58 Liquid Nitrogen cooling25:56 Reading the core ropes29:22 Running and explaining the recovered software32:20 Mike's core rope recovery to date
Bendix Air Data Computer - Part 5: Restoration Finished, It Works! CuriousMarc 2024-01-17 | Our jet fighter analog mechanical computer is operational! We fly the bench at supersonic speeds like it's 1950 all over again. Depstech DS630 endoscope: amzn.to/41ZnA4sDepstech Official Website : www.depstech.com Bendix MG-1 Restoration Playlist: youtube.com/playlist?list=PL-_93BVApb59k-GD2e83E6prrhm5fobtVKen Shirriff articles on the Bendix MG-1 Central Air Data Computer:righto.com/2023/02/bendix-central-air-data-computer-cadc.htmlrighto.com/2023/10/bendix-cadc-reverse-engineering.htmlrighto.com/2024/01/bendix-cadc-pressure-transducers.htmlStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- New! Better quality merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.com- Depstech Endoscopes: depstech.com Get more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 Recap of previous episodes01:34 Bendix computer principle of operation03:26 First round of repairs05:44 Depstech endoscope08:08 First pressure sensor power up10:58 Angle of attack sensor power up12:18 Second round of repairs16:18 It finally works!16:46 Powering the tester with the Apollo inverter18:44 Flight instruments19:52 Demo time!25:08 Outro and beauty shots
HP 410C Vacuum Tube Voltmeter Part 2: AC Probe CuriousMarc 2024-01-09 | We jury-rig a tube based AC probe for our HP 410C VTVM. Will it do better than our modern Keysight multimeter? (Answer: yes)Atkelar's Second HP 410C Restoration: youtu.be/VlpNK7vdQKAStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Wall of weird vintage electrical and electronic clocks new year flip CuriousMarc 2024-01-01 | We had a pretty low key new year's eve at home this time, so we chilled next to the wall of clocks around midnight. We’ve got some heady clock company in there, including a cesium clock, a flown Soyuz clock and a giant vintage Solari flip clock. Happy New Year 2024 to you all.Some previous videos about the clocks:Solari Flip Clock: youtube.com/playlist?list=PL-_93BVApb59Xs5gCX_Sch1LoIm8TcWQ2Soyuz Space Clock youtube.com/playlist?list=PL-_93BVApb5-951yH6TlPobwnQkLYWnDWTI bubble LED clock hack: youtu.be/m_juPAK7I_ICesium Atomic Clock: youtu.be/eOti3kKWX-cAmano punch clock: youtu.be/Dm4FtcmsJXoIBM Blinkenlight Tester: youtu.be/Z8PdWIZFVEkStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- New! Better quality merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Teletype Music! A mechanical Christmas song. CuriousMarc 2023-12-25 | In this short, youtube.com/shorts/VYoy2oieMsI , I coerced a teletype to play a Christmas song.This full video explains the process.Original QST article: drive.google.com/file/d/1DROZ-5wChx-jCNFvJOHm65JZ4pJGvPN-/view?usp=drive_linkMy corrected version is further down below.Stuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- New! Better quality merch on Fourthwall: curiousmarc-shop.fourthwall.com- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/aboutMy corrected Jingle Bells Teletype score below:----------CuriousMarc's Jingle Bells for TTYF stands for FIGSX stands for LTRSZ stands for SpaceCr is Carriage ReturnLf is Line FeedOther letters are as typedDon’t type the actual spaces, they are just for visual aid----------Cr LfFSFSFSXMFS FSFSXEFSFS FSFFSSXRRY ZFFSFSFSFF SSFSFSFSSS FSFSFSFSXC FSXHFSFSFS XRFSFSFSXI FSFSFSFFSS XSTMASFSFS FSFFSSFSFS FSSSFSFSFS FSXZANFSSS FSFSFSFSXD ZAFSSSFSFSFSFSXZHAFS SSFSFSFSFS FSFSFSSSFSFSFSFSXP FFFSSS FSFSFSFSFF FFFSSSFSFSFSFSFFFFFS SSFSFSFSFS FSFSFSSSFSFSFSFSFFFS XPFSFSFSXYFSFSFSXZFS FSFSFFSSXN EWZYFSFSFSFFSSFSFSFS SSFSFSFSFSXEFSXAFSFS FSXRFSFSFS XZFSFSFSFFSSXTOZALFS FSFSFFSSFSFSFSSSFS FSFSFSXLCr Lf----------------Time stamps:00:00 The original QST article01:14 Trying the QST score03:30 Upgrading to a Teletype orchestra07:56 Editing the tape14:18 Corrected tape rehearsal16:36 Jingle Bells Teletype Performance
Teletype Christmas Song Duet #vintageelectronics #Christmas CuriousMarc 2023-12-25 | Stuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Apollo Comms Part 29: Downvoice CuriousMarc 2023-12-22 | We back out the last remaining modification from our NASA receiver and return it to its original Apollo voice channel. If we are successful, we'll get to hear the voice from the astronauts the exact same way it was transmitted during the missions. And I hopelessly butchered the name of our hero engineer that left the helpful notes on the equipment, it's Frank Landspurg, not David Landsman! Bravo Mr. Landspurg. His obituary says that he was working for Motorola and supporting the Apollo missions, and passed away in 2014.Apollo Comms Playlist: youtube.com/watch?v=v49ucdZcx9s&list=PL-_93BVApb58SXL-BCv4rVHL-8GuC2WGbLinks to doc:curiousmarc.com/space/apollo-s-band-communicationsvirtualagc.github.io/virtualagc/QuestForInfo.htmlibiblio.org/apolloibiblio.org/apollo/Documents/HSI-481260.pdfElevator Music Credit: Crinoline Dreams by Kevin MacLeodOur sponsors- PCBWay: fast turn PCBs, pcbway.com- ElectroRent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comSupport the team on Patreon: patreon.com/curiousmarcBuy shirts on Teespring: teespring.com/stores/curiousmarcs-storeLearn more on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 Our Apollo receiver has been modified05:20 Reverting the modification07:41 Retuning the filter assembly11:40 First receiver tests13:38 How to extract downvoice with a ham radio15:45 First voice trials, not working!16:49 Tracking the fault in the spacecraft transmitter20:35 Receiving downvoice!Correction: 03:26 Frank Landspurg (not Landsman)Correction: 05:09 Frank Landspurg (not Dave Landsman)
TMG-303 Test Message Generator Repair CuriousMarc 2023-12-16 | We got a beautiful and complicated CDC TMG-303 Teletype Tester from a viewer. Which does not work and does not have any documentation. But that's not going to stop us, right?Usagi Electric Channel: youtube.com/@UsagiElectricStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
HP 410C Vacuum Tube Voltmeter Restoration CuriousMarc 2023-11-25 | Another classic Hewlett-Packard instrument saved from the trash bin: the HP 410C VTVM (Vacuum Tube Voltmeter). Stuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
My 1956 STW-10 Friden Calculator CuriousMarc 2023-11-19 | Just a few beauty shots of my Friden STW-10 calculator.More videos about it here: youtube.com/playlist?list=PL-_93BVApb5_GbzkFwdKpuyPo8Ty83h8bStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
MITE Tactical Teleprinter - military digital communications from 1958 CuriousMarc 2023-11-16 | We marvel at a MITE AN/TGC-14A(V) Teleprinter, a miracle of teletype miniaturization from 1958. Imagine, only 41 lbs!Teletype model 19 restoration playlist: youtube.com/playlist?list=PL-_93BVApb5-9eQLTCk9xx16RAGEYHH1qASR33 Teletype restoration playlist: youtube.com/playlist?list=PL-_93BVApb5-84G5kmgfuu7TQduTMc73H3M Whisper Writer Telex: youtu.be/4ta-AWDALyYStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarc"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeodOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Apollo Core Rope Memory (Apollo Guidance Computer Part 30) CuriousMarc 2023-10-27 | Core Rope Memory, which contained the programs that landed man on the Moon in the 1960s, is insanely complicated. But that won't stop Mike from making a custom reader for it, so he can recover Apollo Guidance Computer programs lost to history. Mike Stewart's Core Rope Visualizer: http://apolloguidance.computer/rope/Apollo Guidance Computer Restoration Playlist: youtube.com/playlist?list=PL-_93BVApb59FWrLZfdlisi_x7-Ut_-w7Core Memory Videos:youtu.be/AwsInQLmjXcyoutu.be/7ozNMgx7WtQyoutu.be/e9ih93tuH1kLook Mum No Computer Core Rope Drum Machine: youtu.be/zytjONYkU94Mike's Electric Stuff Soviet Dialer: youtu.be/tPT6nIRFI_IStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 Intro: Apollo Guidance Computer restoration02:21 What is core rope memory?05:16 Previous core rope recoveries with our AGC06:44 Our AGC is sold at auction07:36 Mike's core rope reader prototype11:09 Last minute core rope "hack" for Apollo 1114:04 Software recovered so far14:48 Trying the reader for the first time and error17:56 Core rope explanation: data encoding20:13 Transformer rope is not core rope21:24 Core rope explanation: reading using bistable cores26:09 Core rope explanation: molybdenum permalloy cores28:22 Experimental demo of moly cores31:49 Core rope explanation: addressing with inhibits33:59 Apollo core rope simulator, inhibit wires35:56 Set and reset wires37:45 Parity wires and the design error45:02 Mike fixes the reader and tries again47:38 Success! Congrats Mike!
8 Floppy drive final repair and realignment procedure (ft. Usagi Electric) CuriousMarc 2023-10-10 | Get your 3D printed parts from PCBWay: pcbway.com/rapid-prototyping/manufactureUsagi Electric (Electric Bunny in Japanese) is visiting us. And I have the very floppy drive his Centurion minicomputer is missing. In this episode, we repair the head actuator brake with a professionally printed 3D part, and demonstrate how to realign the drive with a professional alignment diskette as well as without it. There will be professional bunnies at the end, promised.See Usagi Electric install this very floppy drive in his Centurion:youtu.be/-jA3ATLpUtMyoutu.be/X3y7OUERyJgAll you never wanted to know about 8" floppies:youtu.be/oL0LXSE1jeMRepair of the previous 8" floppy drives:youtu.be/ZWosbEn3YbEyoutu.be/suXx5ExyWeEStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Diode Sampler Magic CuriousMarc 2023-09-29 | The HP plugin we just repaired has a magic RF circuit in it: a diode sampler that goes up to 18 GHz. It is well worth playing a little more with it, and understanding how this extraordinary circuit, which is still relevant today, actually works.Previous video about the HP 5257A 18 GHz transfer oscillator plugin:youtu.be/sl_Zh-IxVTAFurther documentation on my website: curiousmarc.com/instruments/hp-5245l-nixie-counter#h.ixw2jz3t1jtbStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
HP 5245L Nixie Counter - Part 7: HP 5264 Preset, HP 5262 Time Interval, HP 5257 Transfer Oscillator CuriousMarc 2023-09-25 | We test a pile of new plugins, and fix the king of them all: the HP 5257A 18 GHz Transfer Oscillator. While we are at it, we demo the HP 5264A Preset Unit and the HP 5262A Time Interval Unit. This completes our repair-a-thon! No kidding, we repaired them all, the main counter and 10 plugins! 5245L Repair-a-thon Playlist: youtube.com/playlist?list=PL-_93BVApb5_MQBUOVLgdKCaUPY1zaPh_Further documentation on my website: curiousmarc.com/instruments/hp-5245l-nixie-counter#h.ixw2jz3t1jtbStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 Recap of previous episodes00:43 New pile of plugins!01:47 HP 5264A Preset Unit Plugin Test04:11 HP 5262A Time Interval Unit Test05:53 HP 5257A Transfer Oscillator Test08:05 Transfer Oscillator Explanation13:27 Fault #1 Debug20:00 Fault #2 Debug25:14 It works again26:41 Now part the Apollo setup!
Whisper Writer Telex to Radio Teletype Conversion CuriousMarc 2023-09-03 | In this revenge-of-the-Teletype episode, we reverse engineer our super-modern (1984!) 3M Whisper Writer Telex machine, and turn it into a fully featured RTTY receiver and Teletype tester.Get your PCBs from our sponsor PCBWay: pcbway.comSchematics:drive.google.com/file/d/1tic2lBHaCRsTtSF1C1Mao24fTiy_fqKu/view?usp=share_linkFull project info (Kicad files, ROMs, etc...) on my website:curiousmarc.com/computing/3m-whisper-writer-telexStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
HP 5245L Nixie Counter - Part 6: HP 5255A 12.4 GHz Plugin Repair CuriousMarc 2023-08-15 | We repair a 12.4 GHz Nixie frequency counter plugin, the HP 5255A. It takes a double length episode to get it to behave, and you won't believe what we find at the end. 5245L Repair-a-thon Playlist: youtube.com/playlist?list=PL-_93BVApb5_MQBUOVLgdKCaUPY1zaPh_My HP 5255A manual high resolution scan:archive.org/details/hp-5255-a-frequency-converter-operating-and-service-manual-05255-9022-may-1967Further documentation on my website: curiousmarc.com/instruments/hp-5245l-nixie-counter#h.ixw2jz3t1jtbStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 Summary of previous episodes00:53 The very broken 12.4 GHz plugin02:19 Operating principle (with elevator music)06:30 Opening the unit09:35 Faulty video amp?12:53 Debugging the Automatic Gain Control15:48 Debugging the bias17:32 RF self-oscillation hell!22:11 Nursing the amp back to life25:00 Debugging the power meter circuits32:45 Debugging the gate extender37:56 Finally measuring microwaves!39:20 Discovery of another video amp issue42:12 Debugging the weird low frequency suckout47:37 Plot twist: RF mixer surprise!52:22 Did we finally repair it?55:42 Epilogue: comparing with another plugin
Adding composite video and sound inputs to a 1976 TV (Panasonic TR-525) CuriousMarc 2023-08-06 | We modify a cute Panasonic TR-525 portable TV to accept video and sound inputs, so we can use it as a retro computer monitor.Stuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/aboutTheme song: Festive Dinner by Pony Music
Bendix Air Data Computer - Part 4: Magnetic Amplifier Magic CuriousMarc 2023-08-03 | Thermal Camera TC001(android): amazon.com/gp/product/B0B7LMB22Q (Apply $20 coupon with Prime: $229)Thermal Camera TC002(IOS): amazon.com/dp/B0BYHP8KM9 (Apply $70 coupon:$229)We power up our analog computer for the first time, and are stumped by evil magnetic amplifiers.Bendix MG-1 Restoration Playlist: youtube.com/playlist?list=PL-_93BVApb59k-GD2e83E6prrhm5fobtVSee Ken’s full explanation of the inner workings of this computer in his blog article: http://www.righto.com/2023/02/bendix-central-air-data-computer-cadc.htmlStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Unassuming Apollo Panel Has Major Role in Apollo 13 CuriousMarc 2023-07-31 | In another piece of little known Apollo 13 electronic trivia, we power up a mostly unknown panel that was in the command module, and was responsible for triggering the Main Bus B Undervolt alarm. As usual in all things Apollo, it is more complicated than you'd think.Apollo 13 Accident Troubleshoot Analysis: youtu.be/ZUeFwyicV8oApollo Guidance Computer Restoration: youtube.com/playlist?list=PL-_93BVApb59FWrLZfdlisi_x7-Ut_-w7Apollo Communications Electronics: youtube.com/playlist?list=PL-_93BVApb58SXL-BCv4rVHL-8GuC2WGbLinks to documentation:CSM Block II Schematics: ibiblio.org/apollo/Documents/HSI-481260.pdfCSM Block I Schematics: ibiblio.org/apollo/ApolloProjectOnline/Documents/CSM%20104%20Systems%20Handbook%2019690124.pdfCircuit Utilization Panel Diagrams: curiousmarc.com/space/apollo-circuit-utilization-panel#h.zi7epqr36uozOur sponsors- PCBWay: fast turn PCBs, pcbway.com- ElectroRent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comSupport the team on Patreon: patreon.com/curiousmarcBuy shirts on Teespring: teespring.com/stores/curiousmarcs-storeLearn more on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
HP 5245L Nixie Counter - Part 5: HP 5261A Video Amplifier Plugin CuriousMarc 2023-07-24 | Our brand spanking new HP 5261A plugin has been in storage since 1972! Authentic HP vintage unboxing experience awaits. Surely, nothing could be wrong with a quality instrument that has been carefully stored for 51 years. Or could it?5245L Repair-a-thon Playlist: youtube.com/playlist?list=PL-_93BVApb5_MQBUOVLgdKCaUPY1zaPh_Documentation on my website: curiousmarc.com/instruments/hp-5245l-nixie-counter#h.ixw2jz3t1jtbStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
HP 5245L Nixie Counter - Part 4: HP 5254A 3 GHz Plugin Repair CuriousMarc 2023-07-20 | We repair our 3 GHz Nixie frequency counter plugin, the HP 5254A. 3 gig, not bad for 1964! Things are spicier than with our previous and tamer 500 MHz plugin, so we have to break out the microwave test equipment.5245L Repair-a-thon Playlist: youtube.com/playlist?list=PL-_93BVApb5_MQBUOVLgdKCaUPY1zaPh_Documentation on my website: curiousmarc.com/instruments/hp-5245l-nixie-counter#h.ixw2jz3t1jtbStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 Summary of previous episodes01:02 Into the broken 3 GHz plugin04:05 Mechanical repair07:52 First try10:09 Multiplier repair12:22 Second try13:36 Multiplier alignment15:36 Third try16:27 Second mechanical repair and realignment22:59 Fourth try - it works!24:20 Measuring the Apollo S-band transmit frequency
RAF Smiths Pitot Static Tester CuriousMarc 2023-06-27 | Straight from her late majesty to us, we get a Royal Air Force pitot-static tester, to help us with our restoration of the Bendix Air Data Computer. Is it old? Yes. Was it cheap? Very much so. Does it work? Sure not. Is it beautiful inside? You are kidding, it's awesome, with stunning steampunk technology from the late 1950's! Are we going to be successful in repairing it? You are going to find out in this video!Bendix MG-1 Restoration Playlist: youtube.com/playlist?list=PL-_93BVApb59k-GD2e83E6prrhm5fobtVStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
HP 5245L Nixie Counter - Part 3: 500 MHz Plugin Repair (HP 5253A and HP 5253B) CuriousMarc 2023-06-12 | It's time to repair our 500 MHz frequency converter plugins, the HP 5253A and HP 5253B. It says in red letters: "CAUTION: DO NOT ATTEMPT DISASSEMBLY OF CAVITY". Really? Guess what we are going to do!5245L Repair-a-thon Playlist: youtube.com/playlist?list=PL-_93BVApb5_MQBUOVLgdKCaUPY1zaPh_Documentation on my website: curiousmarc.com/instruments/hp-5245l-nixie-counter#h.ixw2jz3t1jtbStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 Summary of previous episodes01:00 The many plug ins for the HP 5245L02:25 Making the extender cable03:06 HP 5253 converter principle of operation (with elevator music)07:58 Inspection and tryout of our first HP 5253A plugin10:56 Summary of the first HP 5253B repair11:27 Taking apart the second HP 5253A14:02 Stuck gearing repair15:37 Disassembling the "Do Not Disassemble" microwave cavity19:13 Coaxial resonant cavity explanation (with elevator music)23:05 Reassembling the cavity26:19 Testing the repaired HP 5253A plugin27:15 Comparing with the second HP 5253B cavity28:26 Testing the second HP 5253B plugin
We found the shark in the SHARC DSP #Short #InTheRightOrientation CuriousMarc 2023-06-08 | Antoine (@SiliconInsid on Twitter) brought some cool chips to decap. Here we open a quad SHARC DSP chip. We think that's where the original recipe for fish and chips comes from!Stuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Apollo 13 accident: understanding Houston’s real time debug (Apollo Comms Part 28) CuriousMarc 2023-06-02 | We open up a Block I Apollo AC inverter, which gets us totally sidetracked into the Apollo 13 incident. Using the original schematics, looking how our inverter was hooked up in the power system, we can follow word for word the Apollo 13 raw audio of the debug after the accident. I will go into much more engineering details than what is usually reported, but once you understand this, the flight control loops become both limpid and downright chilling. And then, when we regain our composure and get back to said inverter, more surprises await.Apollo 13 incident composite loop is on my website here:curiousmarc.com/space/apollo-s-band-communications#h.kuc8m1at9uu4An even better way to listen to the Apollo 13 audio is to go to:apolloinrealtime.org/13Select "join at launch-1minute", then pause it and go to mission time 55:54.To get an even better listen, go to the Mission Audio Control tab, and click on EECOM. You'll hear even more of the backroom discussion between EECOM and EPSThe episode about the fuel cell is here:youtu.be/5ZBRw07IbgoLinks to doc:curiousmarc.com/space/apollo-s-band-communicationsvirtualagc.github.io/virtualagc/QuestForInfo.htmlibiblio.org/apolloMusic Credit: Crinoline Dreams by Kevin MacLeodOur sponsors- PCBWay: fast turn PCBs, pcbway.com- ElectroRent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comSupport the team on Patreon: patreon.com/curiousmarcBuy shirts on Teespring: teespring.com/stores/curiousmarcs-storeLearn more on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
RAF Pitot Static Tester Preview - Guess What This is For! #Short #InTheRightOrientation CuriousMarc 2023-05-30 | A quick preview of a mystery instrument I just repaired. Can you guess what what it does? Hint: my minions stole this from the British RAF. Full repair video will follow, that was intense.Stuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
HP 5245L Nixie Counter - Part 2: Repairing the king of Nixie frequency meters CuriousMarc 2023-05-17 | We continue repairing our very broken HP 5245L, and hit some really subtle bugs in this amazing all-transistor machine. Opening the Nixie decoder to reveal its many neons and photo-resistor tree is a special treat. 5245L Repair-a-thon Playlist: youtube.com/playlist?list=PL-_93BVApb5_MQBUOVLgdKCaUPY1zaPh_Documentation on my website: curiousmarc.com/instruments/hp-5245l-nixie-counter#h.ixw2jz3t1jtbStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 Summary of previous episode01:16 Board A21 gate signal repair04:10 Why is it still not counting?06:31 Board A17 fast counter repair11:19 Still not counting right12:28 Board A15 counter/display explanation14:20 Taking apart the Nixie decoder16:25 Board A15 counter neon bulb debug19:22 Reset issue discovery20:48 Nixie decoder reassembly and test21:56 Board A23 reset debug23:39 Reset fault cured25:48 Repaired!
HP 5245L Nixie Counter - Part 1: The King of 1960s Frequency Meters CuriousMarc 2023-05-11 | We start repairing our very broken HP 5245L. It is arguably the king of the Nixie frequency meters of the 1960s. Equipped with the right plug in, it could count up to 18 GHz. Many of them were used in the Apollo communication ground stations. But this digital instrument does not use a single IC: it's all made with individual transistors inside! It feels like repairing a giant IC, but with access to every transistor. We're sure not complaining about it.5245L Repair-a-thon Playlist: youtube.com/playlist?list=PL-_93BVApb5_MQBUOVLgdKCaUPY1zaPh_Documentation on my website: curiousmarc.com/instruments/hp-5245l-nixie-counter#h.ixw2jz3t1jtbStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about00:00 The HP 5245L, king of 1960s counters02:06 HP instruments at an Apollo tracking station03:19 Looking inside and first turn on06:04 Power supply check06:30 Crystal oscillator check08:58 Backplane and previous failed repairs10:22 10 MHz Multiplier repair12:25 Board A35 Time Base Repair15:24 Board A19 Input checkout16:41 Board A21 Function Control checkout19:17 Board A21 repair25:28 The differentiator works!26:27 Gate signal fault27:14 Summary of Episode 1 repairs
Vintage Kollsman Altimeter Repair CuriousMarc 2023-05-07 | Our eBay altimeter that we purchased for the Bendix Air Data Computer restoration is very broken. Can we repair it? Not too sure about that, but at least we'll get to see what's inside, and it's very pretty!Bendix MG-1 Restoration Playlist: youtube.com/playlist?list=PL-_93BVApb59k-GD2e83E6prrhm5fobtVStuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
Star Wars Aware Computer - from 1964 CuriousMarc 2023-05-04 | Today is May the 4th! May the force stay strong with your vintage computer!Stuff that supports the channel:- Amazon links for the tools I use in the lab (supports the channel if you buy from there)curiousmarc.com/amazon-links- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store- Support us on Patreon: patreon.com/curiousmarcOur lovely sponsors- PCBWay: fast turn PCBs, pcbway.com- Electro-Rent: electrorent.com- Keysight: test instruments: keysight.com- Samtec: connectors: samtec.com- R&D Microwaves: rdmicrowaves.comGet more technical info on the companion site: curiousmarc.comContact info: youtube.com/curiousmarc/about
