![Edwin Steiner](/img/default-banner.jpg)
- 61
- 46 914
Edwin Steiner
Registrace 23. 07. 2013
I make videos about physics and about coding.
You can support me at www.subscribestar.com/edwinsteiner .
You can support me at www.subscribestar.com/edwinsteiner .
The Pentax Electro Spotmatic: Reverse-engineering a marvel of 1971's Japanese electronics [Part 6].
The Pentax Electro Spotmatic was the first SLR camera with automatic shutter control.
In these videos I share what I have found out by reverse engineering this camera
and I go through a systematic trouble shooting and repair of the electronics of
a Pentax Electro Spotmatic.
This is part 6, in which we check the remaining parts of the camera
and go through the full calibration of the electronics.
Part 1 is here: czcams.com/video/GrQI07X9Zi0/video.html
Part 2 is here: czcams.com/video/jkEPIudCGIo/video.html
Part 3 is here: czcams.com/video/HOnj1KhhlGY/video.html
Part 4 is here: czcams.com/video/G1OOaY8hXs0/video.html
Part 5 is here: czcams.com/video/6Fi4C9pPbLg/video.html
Please contact me in the comments or via email if you want to repair an Electro Spotmatic!
I can provide schematics for the camera and test setups and design files for the breakout system.
00:00 Intro
00:41 Timing contact
01:37 Mirror box contact
02:33 Stop-down switch
03:50 REF Calibration: Challenges
05:01 REF Calibration: Degrees of Freedom
05:56 REF Calibration: Sequence
06:46 REF Calibration: Log expansion
07:40 REF Calibration: Log compression
08:15 REF Calibration: Meter slope
09:08 REF Meter calibration: Setup
10:14 REF Meter calibration: Procedure
11:19 REF Meter calibration: (Non-)Linearity
12:25 Meter calibration: Results
13:11 Calibration: Aperture step size
16:16 Calibration: ASA divider
20:11 Threshold adjustment range
21:27 Modifying the threshold range
22:10 Threshold range results
22:44 Calibration: Stop-down mode
25:10 Calibration: Battery check
26:02 Shutter time measurements
27:06 Evaluating the measurements
27:37 Results for shutter times
29:29 Debugging: Shutter time fluctuations
30:03 Debugging: Meter calibration
30:34 Debugging: Aperture problems
33:40 Debugging: Analysis of variance
35:55 Calibration: Threshold adjustment
37:55 Finishing the PCB
38:16 Calibration: Timing contact
39:02 Removing the test harness
39:32 Power supply capacitor
39:38 Reassembling the camera
43:34 Gluing the leatherette
45:23 Final results
47:17 Vcharge ripple
47:46 Conclusion
Video about gluing leatherette: czcams.com/video/cBM0dHtrs9U/video.html
Pentaxforums entry about the Electro Spotmatic: www.pentaxforums.com/camerareviews/pentax-electro-spotmatic.html
In these videos I share what I have found out by reverse engineering this camera
and I go through a systematic trouble shooting and repair of the electronics of
a Pentax Electro Spotmatic.
This is part 6, in which we check the remaining parts of the camera
and go through the full calibration of the electronics.
Part 1 is here: czcams.com/video/GrQI07X9Zi0/video.html
Part 2 is here: czcams.com/video/jkEPIudCGIo/video.html
Part 3 is here: czcams.com/video/HOnj1KhhlGY/video.html
Part 4 is here: czcams.com/video/G1OOaY8hXs0/video.html
Part 5 is here: czcams.com/video/6Fi4C9pPbLg/video.html
Please contact me in the comments or via email if you want to repair an Electro Spotmatic!
I can provide schematics for the camera and test setups and design files for the breakout system.
00:00 Intro
00:41 Timing contact
01:37 Mirror box contact
02:33 Stop-down switch
03:50 REF Calibration: Challenges
05:01 REF Calibration: Degrees of Freedom
05:56 REF Calibration: Sequence
06:46 REF Calibration: Log expansion
07:40 REF Calibration: Log compression
08:15 REF Calibration: Meter slope
09:08 REF Meter calibration: Setup
10:14 REF Meter calibration: Procedure
11:19 REF Meter calibration: (Non-)Linearity
12:25 Meter calibration: Results
13:11 Calibration: Aperture step size
16:16 Calibration: ASA divider
20:11 Threshold adjustment range
21:27 Modifying the threshold range
22:10 Threshold range results
22:44 Calibration: Stop-down mode
25:10 Calibration: Battery check
26:02 Shutter time measurements
27:06 Evaluating the measurements
27:37 Results for shutter times
29:29 Debugging: Shutter time fluctuations
30:03 Debugging: Meter calibration
30:34 Debugging: Aperture problems
33:40 Debugging: Analysis of variance
35:55 Calibration: Threshold adjustment
37:55 Finishing the PCB
38:16 Calibration: Timing contact
39:02 Removing the test harness
39:32 Power supply capacitor
39:38 Reassembling the camera
43:34 Gluing the leatherette
45:23 Final results
47:17 Vcharge ripple
47:46 Conclusion
Video about gluing leatherette: czcams.com/video/cBM0dHtrs9U/video.html
Pentaxforums entry about the Electro Spotmatic: www.pentaxforums.com/camerareviews/pentax-electro-spotmatic.html
zhlédnutí: 373
Video
The Pentax Electro Spotmatic: Reverse-engineering a marvel of 1971's Japanese electronics [Part 5].
zhlédnutí 346Před rokem
The Pentax Electro Spotmatic was the first SLR camera with automatic shutter control. In these videos I share what I have found out by reverse engineering this camera and I go through a systematic trouble shooting and repair of the electronics of a Pentax Electro Spotmatic. This is part 5, where we install the new log compression circuitry and CdS cells and analyze the effect of different color...
The Pentax Electro Spotmatic: Reverse-engineering a marvel of 1971's Japanese electronics [Part 4].
zhlédnutí 332Před rokem
The Pentax Electro Spotmatic was the first SLR camera with automatic shutter control. In these videos I share what I have found out by reverse engineering this camera and I go through a systematic trouble shooting and repair of the electronics of a Pentax Electro Spotmatic. This is part 4, where we test the solenoid and the comparator and switching circuits, characterize the JFET buffer and the...
The Pentax Electro Spotmatic: Reverse-engineering a marvel of 1971's Japanese electronics [Part 3].
zhlédnutí 267Před rokem
The Pentax Electro Spotmatic was the first SLR camera with automatic shutter control. In these videos I share what I have found out by reverse engineering this camera and I go through a systematic trouble shooting and repair of the electronics of a Pentax Electro Spotmatic. This is part 3, where we characterize CdS cells and find out how to match the circuits of the camera to sensors that are a...
The Pentax Electro Spotmatic: Reverse-engineering a marvel of 1971's Japanese electronics [Part 2].
zhlédnutí 444Před rokem
The Pentax Electro Spotmatic was the first SLR camera with automatic shutter control. In these videos I share what I have found out by reverse engineering this camera and I go through a systematic trouble shooting and repair of the electronics of a Pentax Electro Spotmatic. This is part 2, where we repair the battery compartment and test the light sensitivity of the camera. This part also expla...
The Pentax Electro Spotmatic: Reverse-engineering a marvel of 1971's Japanese electronics [Part 1].
zhlédnutí 2KPřed rokem
The Pentax Electro Spotmatic was the first SLR camera with automatic shutter control. In these videos I share what I have found out by reverse engineering this camera and I go through a systematic trouble shooting and repair of the electronics of a Pentax Electro Spotmatic. This is part 1, where we discuss disassembly of the camera and its elaborate power supply concept. Please contact me in th...
Why Roger Penrose (@Jordan Peterson) is wrong about quantum mechanics
zhlédnutí 2,6KPřed 2 lety
In this video I explain why some statements by Sir Roger Penrose about the alleged inconsistency and incompleteness of quantum mechanics are wrong. I discuss crucial points of a consistent understanding of quantum mechanics, including the notion of the observer, compatibility of quantum-mechanical predictions, interference and decoherence, the so-called "measurement problem", observer dependenc...
The vertex algebra of one free boson: Part 5: Light-cone coordinates.
zhlédnutí 281Před 2 lety
This video is the fifth part of a mini-series about the appearance of the vertex algebra of one free boson from the physical point of view. In this part, we define light-cone coordinates and use them to get more insight about the left- and right-moving modes and about the zero mode. The video is aimed at people who have some knowledge of calculus and linear algebra but who don't necessarily hav...
The vertex algebra of one free boson: Part 4: Left/right-movers.
zhlédnutí 354Před 2 lety
This video is the fourth part of a mini-series about the appearance of the vertex algebra of one free boson from the physical point of view. In this part, we discuss the right-moving and left-moving modes of the field. The video is aimed at people who have some knowledge of calculus and linear algebra but who don't necessarily have much background in physics. 0:00 Introduction 2:49 Recap 5:25 A...
The vertex algebra of one free boson: Part 3: Phase space.
zhlédnutí 177Před 2 lety
This video is the third part of a mini-series about the appearance of the vertex algebra of one free boson from the physical point of view. In this part, we look at the phase space trajectories of the modes of oscillation and we define complex-valued variables that combine the notions of amplitude and phase of a mode. The video is aimed at people who have some knowledge of calculus and linear a...
The vertex algebra of one free boson: Part 2: Modes.
zhlédnutí 206Před 2 lety
This video is the second part of a mini-series about the appearance of the vertex algebra of one free boson from the physical point of view. In this part, we take an elementary look at the Fourier modes of the field and their classical equations of motion. The more elegant complex Fourier modes will be introduced in the next part. The video is aimed at people who have some knowledge of calculus...
The vertex algebra of one free boson: Part 1: The field.
zhlédnutí 797Před 2 lety
This video is the first part of a mini-series about the appearance of the vertex algebra of one free boson from the physical point of view. It is meant as a counterpart to Michael Penn's video about the mathematics of this particular vertex algebra. The video is aimed at people who have some knowledge of calculus and linear algebra but who don't necessarily have much background in physics. 0:00...
Introduction to the series "Understanding quantum mechanics".
zhlédnutí 1,1KPřed 3 lety
This video introduces my series "Understanding Quantum Mechanics". I say a few words about why I think this series is needed and what its intended scope is. In the second half, I recommend a few books to use along with my videos. Some important comments about materialism / realism versus the scientific worldview and about the meaning of "physical" conclude the introduction. Note: For our purpos...
Understanding quantum mechanics 3.1: The principles (part 1).
zhlédnutí 1,5KPřed 3 lety
Episode 3 establishes the principles of quantum mechanics. In this first part, we discuss the representation of knowledge. Topics we encounter include: the uncertainty principle, the choice of the observer, the wave function, compatible and complementary observables, Born's rule, the Hilbert space and its inner product, the physical interpretation of the wave function, and the so-called "collap...
Understanding quantum mechanics 2: Uncertainty and the weirdness of classical physics.
zhlédnutí 1,4KPřed 3 lety
In this episode, we first explore the concepts of uncertainty and probability as aspects of the common empirical basis of classical and quantum physics. Then we formulate the basic assumptions of classical physics and their consequences, in particular classical determinism. Finally, we discuss the weird but popular metaphysics suggested by (or at least compatible with) classical physics. The fi...
Understanding quantum mechanics 1: A physical theory.
zhlédnutí 1,7KPřed 3 lety
Understanding quantum mechanics 1: A physical theory.
The Meaning of Plus in Quantum Mechanics [feat. Schrödinger's cat]
zhlédnutí 1,7KPřed 3 lety
The Meaning of Plus in Quantum Mechanics [feat. Schrödinger's cat]
Was bedeutet das Plus in der Quantenmechanik? [feat. Schrödingers Katze]
zhlédnutí 537Před 3 lety
Was bedeutet das Plus in der Quantenmechanik? [feat. Schrödingers Katze]
PDF file format introduction and crashing readers with wickedly invalid PDFs
zhlédnutí 256Před 4 lety
PDF file format introduction and crashing readers with wickedly invalid PDFs
Handmade C++: custom memory manager for libjpeg-turbo
zhlédnutí 450Před 4 lety
Handmade C : custom memory manager for libjpeg-turbo
Handmade C++: LZW Decompression Tuning, Part 1
zhlédnutí 172Před 4 lety
Handmade C : LZW Decompression Tuning, Part 1
Handmade C++: LZW Decompression Testing, Part 2
zhlédnutí 73Před 4 lety
Handmade C : LZW Decompression Testing, Part 2
Handmade C++: Generating tests for LZW decompression
zhlédnutí 172Před 4 lety
Handmade C : Generating tests for LZW decompression
Handmade C++: LZW Decoding, Part 1: initial implementation and debugging
zhlédnutí 493Před 4 lety
Handmade C : LZW Decoding, Part 1: initial implementation and debugging
LZW (Lempel-Ziv-Welch) Decompression: How it works.
zhlédnutí 1,5KPřed 4 lety
LZW (Lempel-Ziv-Welch) Decompression: How it works.
Handmade C++: datastream refancyment [Part 5, context reporting]
zhlédnutí 12Před 4 lety
Handmade C : datastream refancyment [Part 5, context reporting]
Handmade C++: datastream refactoring [Part 4: context query]
zhlédnutí 51Před 4 lety
Handmade C : datastream refactoring [Part 4: context query]
Handmade C++: datastream refactoring [Part 3]
zhlédnutí 30Před 4 lety
Handmade C : datastream refactoring [Part 3]
Thanks for the video. My XP80 had the glue problem. It was only on the underside of the keys so no damage anywhere.
Please post your "Buy me a coffee" link, you gave me the confidence to take this on and I really appreciate it.
QT perfectly explained and top background: LEGO space set from 1979-1980. Lego sets from your childhood? Many thanks 😊
Indeed, well spotted. I was born in 1978 and I was *obsessed* with LEGO, in particular space LEGO, throughout my childhood. Glad that you enjoyed the video. Be sure to check out my other, more comprehensive, QM videos. (Also, stay tuned, though my pace is glacially slow.)
Hi. I would like to say a huge thank you for this series of videos about Pentax Electro Spotmatic. I bought myself such a camera for restoration, but the electronics worked in it. Recently, I accidentally put a 4LR44 battery with the wrong polarity and the exposure meter stopped functioning. I would really like to repair it, but I can't find an electronic repair circuit. Problem: The exposure meter only does not react to light. ISO switching, exposure correction, aperture data transmission systems change the values of the exposure meter, but only when the mode is turned off. If you turn on the exposure measurement mode, the camera will work out 1/1000 and not react to light. I will be very grateful for any help in solving this problem. Thank you in advance.
@@Vanya_Avan Hello! Sorry to hear about your troubles. I will be traveling the next days, so I cannot look into it immediately. Maybe you can send more details about the behavior of your camera to my email: edwin dot steiner at gmx dot net. In particular, what do you mean by "measurement off"? Do you mean the open aperture metering mode?
@@EdwinSteiner Thank you! That's right, when the exposure metering mode is turned off, the arrow reacts to switching other parameters. I will email you a more detailed description of the problem and a link to a video of the problem.
Great video, thank you for a very thorough job. I disassembled my JV-80 and it has this problem really bad! I read that lye can have a very high pH in high concentrations, will lye dissolve this glue? Also a few of my keys don't work, is it possible glue got into the switches? Should I remove the ct. board and clean all of those contacts? Do you have any advice on doing that? And what kind of epoxy did you use? Thanks again. Cheers from California
yes, lye will probably work well. just give it enough time to dissolve the glue. some keys not working is likely due to oxidation or dirt in the switches, not the glue. i had some dead keys before and i could fix them by disassembling and cleaning the contacts *very carefully* with isopropyl alcohol and lightly rotating an eraser head of a pencil on the contacts and then dusting off.
@@EdwinSteiner Thank you very much Edwin. I'll pull the circuit board and do the cleaning as you described. I really appreciate your work here. Cheers.
@@EdwinSteiner LYE UPDATE: I highly recommend Lye, I had read that it can have a pH of 12-14 in high concentrations, so I bought 100% lye crystals, mixed a strong concentration: about 1/3 cup (80mL) of crystals in about 1/2 gallon (1900 mL) water and let it sit for about 18 hours, the weights either had fallen out or fell out of 20 of the white keys and 3 of the black keys with no prying, and no visible red glue on them. 2 more white key weights pried out easily. I'm letting the rest sit in a new equally strong solution for another 24 hours or so.
@@EdwinSteiner Lye Update 2 : After a 2nd soak of 12 hours all of the weights either fell out on their own or came out very easily with light prying using a dental pick. So for anyone whe can't find the drain cleaner he used or can't find the pH of common drain cleaners (I couldn't) I recommend lye. Of course you'll want gloves and eye protection.
Just scored one of these in Thailand at a flea market for the equivalent of €3.20. Still need a battery, and lens though.
DITTO
I have a jv80 but it's dead but it's not red glue. I think it's been fixed. ❤
Because of this video revealing the hand built electronics vs the ES 2 circuitry....as a lifetime user of Pentax for over 50 years. HS photog at 14 yrs old... now 67 and still shooting my 1978 Pentax 6x7. I just bought 10 yes TEN MINT 5+++ electro spotmatics out of JAPAN. the rarity of a mint condition 100% operational 1970 camera is REMARKABLE. The Electros can be found international ebay etc for around $75 to $125 usd plus $30 shipping direct from Japan...
Amazing! Congratulations on your purchase! They are very special cameras, marking both the end of the era of fully analog, discrete electronics and the beginning of the era of automatic electronic SLRs.
I have to do my JD-800 😒😒
Great, great, great job!!
The effort you've put into an obscure and somewhat forgotten camera is remarkable - mazel tov! Now I'm looking to buy one knowing that I have a very well researched video to refer to if it's broken. 😀
this happened to me, had to hand scrape it with a lino knife
Just started the same repair on my Roland EP 9. This video was very helpful. Thank you.
What drain cleaner did you use? Did you try Lye?
Thanks for this video - I had to apologise to my kid tonight - his Roland EP7-II started having sticky keys. I was insinuating he was less than careful with a bowl of something sugary, turned out it was a chemist who was less than careful. Opened it to find a blob of red stuff on the backplate, but fortunately the electronics are fine. Thanks for taking the time to document this, seems I’ve got a job for the weekend now.
@ 36:35 It sounds like an OBVIOUS STATEMENT. But the results of experiments done at CERN, for instance, are far from obvious. They are statistical interpretations of data and thus partly arbitrary. Whether these interpretations have anything to do with an observed reality isn't obvious at all. So, I think your statement is a philosophical statement.
Wonderful and scary… but I fear that mine is in dire need of this treatment 😢
I was simply looking for some information about old Pentax film camera. And now I got into this great video about theory and reality. Who is this gentleman??
I'm glad that you liked it! The quantum mechanics videos are the reason I created the channel. The Pentax project was more of an accidental excursion. There will be more QM videos but they take a long time to write and produce. Due to the low number of videos I did not want to split into multiple channels. Now I know that at least one person cross-discovered the other topic.
By far, the best layman introduction to QM. Well done indeed!
Thanks! It's good to know that people still find the videos now and then. The algorithm really punishes channels that put quality over frequency. I'm working on further QM videos right now but they take a long time to finish.
Great video! I was wondering if you would be able to share a link to the slotted screw driver you used (the one that has a "5" on it @5:32)? I've been looking for one of these and haven't been able to find one!
Thanks! I made this slotted screwdriver myself using a Dremel to grind the slot into a regular old slotted screw driver we had lying around. I also had to grind it a bit flatter to make it fit. So, unfortunately, I cannot give you a link. If you don't want to make it yourself, you could try searching for "face spanner", which I think is the name for a tool with two frontal prongs for turning fasteners.
Quantum mechanics is not known to be logically inconsistency, but quantum mechanics predicts some things which do not happen in nature. The cosmological constant problem would be an example. If it predicts something that is so far off, quantum mechanics does not describe reality and is merely an approximation (an approximation that gets one number very wrong). It's simply the best model we have got at the moment for everything except gravity. We need a new theory.
Dear Edwin, this is really amazing what you did an presented here. Not just the analysis, but designing and producing all the gadgets represents a huge amount of work. You can easily train someone and run a global repair shop for these cameras!
I got an Electro Spotmatic back in 2018 and despite being in awful condition (missing hotshoe, corrosion, etc.), the light meter surprisingly still worked! Until 2019 that is. Ever since I found myself using the camera less but as of today, this video helped me get it working again :) Excellent work and thank you very much for sharing and preserving knowledge about these old cameras :)
Hi Edwin, your explanation of the electronics' function is amazing. Without it I would not be able to understand the function fully. Thanks!
The Pentax engineers put a lot of brains into this relatively small number of components.
Hello. I have just purchased one of these I live in UK so had to get it imported. Luckily my copy works. My PCB looks the same as yours but my battery compartment is different. I have no spring inside camera the spring on my version is inside the removable screw on cover. The battery polarity is the same as yours.. I also have the ES which has spring inside the camera and opposite polarity. My electro spotmatic has a lower serial number than yours also. Thank you for all your amazing work. Mike.
Hello Mike! Congratulations for getting a working one! Interesting that a camera with the lower serial number has the spring in the removable screw, which is the better design for this polarity, in my opinion (no risk of shorting anything out with the spring and easier maintenance of the spring).
Hello Edwin. Yes. I can send photos if you want them. I cant find your email here. I have a realy big spotmatic collection and lenses by the way. Mike @@EdwinSteiner
I have watched this series twice. I am so impressed. Thank you.
awesome work of love and patience
years ago, during the japanese economic bubble, i went fro m Honolulu Hawaii to Yokohama, Japan to do photography there. Fatefully I found myself teaching English and collecting cameras. The next thing i noticed was i had started a hobby of buying selling and sometimes repairing cameras via camera shows and the internet. This video has surprised me in numerous ways.Yes, this tiny camera clearly is "FINE". And YOU have done a wonderful presentation.
Edwin, I love your manner in explaining abstruse concepts simply. But in this case you reified the model: probability is not a property of "nature" but merely a measure of uncertainty in the observer. When you make a move like asserting (in no *uncertain terms* I might add) that there are "no true statements beyond probabilities" you make three errors: (1) you contradict yourself, (2) you can no longer dispute contradictions in a non-question-begging way, and (3) you violate the first principles of thought.
Quite the claims. Re: "probability is not a property of "nature"" -- How do you know that? -- Re: "but merely a measure of uncertainty in the observer" -- Why "merely"? What tells you that what you find in the observer is not a property of nature? Where is the boundary between the observer and "nature"? It's not clear to me what you try to say with the following points, but don't overlook that probabilities may be 0 or 1 in some cases. Probability does not exclude certainty.
@@EdwinSteiner Why "merely"? Because probabilities change dependent on the amount of information afforded the observer. You showed this yourself when you demonstrated that the "Heisenberg cut" can be arbitratrily placed. At least I think this is what you meant to show. If not, then the inconsistency that you claimed to refute is indeed present: for e.g. a scientist who is observing another scientist who is observing an experiment whose result is unknown to the first scientist. I agree with your last sentence. But you assumed, rather than argued for, nature having "no true statement beyond probability". If the formula "no true statements beyond probability" is meant to be univocal with "the only true statements have probability 1" then your problem is the principle of contradiction and its equivalent (or derivative if you prefer) the law of the excluded middle: the claim they affirm of reality that what is real either is, or isn't, with no 'in-between' status is more certain than any argument you can make to the contrary - indeed you have to affirm them in order for there to be such a thing as contrary! I appreciated your clear rhetorical manner and the time you put into the video - you are some teacher! But mistaken here I think.
Great: have you thought about doing a series on reverse engineering stuff? Your channel has interesting technical content, but lacks direction which is possibly why you haven't got many subscribers despite your talent. Also, 50% views/subscriber for your recent series is exceptionally high compared to 10% which is considered good.
I’m in, this has happened to me with devastating effects 😢
Diving in...here goes nothing
Thank you Edwin for sharing your knowledge, but above all for the clear way that is perfectly understood. I will appreciate the 2nd part of the video and also if you could make a video with that understandable explanation capacity that you have, on the mathematical representation of the quantum state of a qubit in the Bloch sphere. What is not clear to me is how the complex exponential initially has an exponent of a difference of angles Phi to finally remain only Phi.
Thanks! The 2nd part is planned but it will take a while. Some other QM videos will be published before that. I'm not sure what you are asking about the Bloch sphere. Maybe you can give some more context or a pointer to the mathematical expression you are confused by.
Thanks so much for making this, now i know why one of my Jv-80’s keyboard key is jammed up so bad lol.. Looks like quite the undertaking to clean and replace all this awful red glue!
Great job , thank you for sharing.👍
For Dutch readers, I have used HG gootsteenontstopper to remove the red glue from the keys (let it stay in overnight) and glued the weights with Bison kit transparant contact glue.
I can't find his drain cleaner where I live in California, I read that high concentrations of lye an have even a higher pH than he used so I'm going to try lye. I'll look for the Biscon glue, thanks.
Hello Edwin. I am incredibly impressed with your knowledge, skills and work method. This is a shock for me. And although I have some knowledge in the field of automation and electronics, I would not be able to develop such an interesting repair method. I am passionate about the Pentax brand and have been repairing old Spotmats for some time. Rather for my own collecting purposes. I came across your video series on YT czcams.com/video/lS4M9BsmCyU/video.html Encouraged by your success in repairing the Pentax Electro, I decided to try repairing my ESII. You have written and said in videos that you are willing to help anyone who would like to try this experiment That's why I'm asking you for help and sharing what you can so that I can repair my ESII. I haven't found any other way to contact you, so I'm writing here. It's best to write to my address: ituitam@vp.pl Regards, Ireneusz
Wow so talented.
I am so impressed with your skills. Fantastic job. So interesting.
I'm going to have to do this to my JV-80 - hence why I watched this video. The topmost E flat and A flat keys are stuck every time I go to play it. I can free them up by wiggling them, but it needs a more permanent fix.
Good luck! Consider checking the comments for tips and experiences from multiple people.
@@EdwinSteiner I certainly did!
Are you going to do more camera repairs? This was a very nice series even thought I didn't understand the details at all.
Hello and thanks! No, other camera repairs are not planned at the moment. This was a quite unique project for me. Future planned videos are mostly about physics plus maybe some programming and electronics.
@@EdwinSteiner Cool. It was a really interesting series. Noone has gone to that level of detail on camera repair. And I've seen most of them.
I'm curious about that key after touch strip. Does that strip also inhibit the sound when you let go of the key or are there individual felt pads for each key that do this? I had the Roland authorized service center replace a broken key about 20 years ago. When I got it back the new key was quiet but many of the other keys were still making a lot of noise (when released).
Thank You so much for this video! It helped me a lot with keybed of JD-800.
I think you can confidently regard yourself as a world leading expert on this model; others will be referencing YOU for advice. My ES2 still works, but usually caps at 1/1000. (Turning the camera upside-down reduces the weight of the mirror and sometimes helps with this.) Anyway, I found you on the Pentax Forum and will subscribe here as well. Thanks for saving this example from the past and keeping it from being scrapped.
Thanks for the vid, I was able to save my JV-1000. I was driving home and someone left the roland on the side of the road because of the glue
That's was amazing series. Thanks for your work!
Hi. Could you be so kind as to tell me what the active ingredients are in "Mellerud Rohr Frei" I'm in South Africa and want to get something equivalent locally. Thanks
Hi! The only ingredient you need is sodium hydroxide (lye), plus warm water and patience. The longer you leave the keys in there, the easier the job. It does not affect the keys at all but the lye may be corrosive to the metal weights, so if you care about them, you may check on them now and then.
I used caustic soda dissolved in a bucket of water to get rid of the glue on my U20 etc never found a good glue to put the weights back on. On my JD800 I bought new keys from Roland at about £100, well worth it IMHO.
Hi Edwin, long time no see since TRF closed. And great video summarizing a lot TRF stood for. Let's maybe reconnect, we had such a great discussion about "immortality" of QM observer if you remember :)
Hi, and thanks. I'm quite proud of this video. It should really get more views. The fact that it is the most disliked of all my videos says something about the dismal state of QM education, I think. I don't know what I said in our discussion but thankfully I downloaded all my comments from TRF some time before it was shut down, so I can check. :) I have at least three QM videos in the pipeline after I'm finished with the camera videos. Unfortunately it is a huge amount of work to make such a video and not a kind of work I particularly enjoy, but there are still some explanations I need to get out there.
@@EdwinSteiner I saved a lot of discussions too and use Wayback Machine for the articles and I still talk to Lubos on fb sometimes :) Are you on fb or where can we chat about QM education?
I'm not on facebook and I don't use any social media besides youtube. Comments about QM education are very much on-topic for my QM videos, so youtube comments are fine.
Breaux custom concrete