EEVblog Electronics Community Forum
EEVblog => EEVblog Specific => Topic started by: SeanB on October 23, 2012, 07:36:31 pm
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EEVblog #375 - Sony Video 8 Camcorder Teardown (https://www.youtube.com/watch?v=HiXZQNOlnnk#ws)
Dave doing the dirty on a old Sony camcorder. 1985 model.
Video problems most likely the (in)famous Sony Cap problems, this unit is old enough to be in at the first batch of problem caps. The SM parts on the boards are glued down as the boards were wave soldered......
Delay line is there as part of the PAL colour system, where you need a reference of the last line chroma to do the addition and inversion that made PAL a superior system with regards to colour shift ( NTSC -Never Twice Same Color, though it really stood for National Television Standards Committee) on video. Initially meant for signal fade during broadcast, but it was robust enough to work well with the phase shifts on video recorders, where speed changes would result in small colour level changes rather than colour shifts.
Nice camera, i have broken many of them apart, as the parts are obscenely expensive, even by Sony standards. They were obsoleted very fast as well.
Hi8 though was a good tape system, capable later on of really good resolution, approaching broadcast quality. It used fine chrome oxides and later metal evaporated tapes and higher power write, which probably goes part way to explaining the poor video, as it is not compatible with this early version, as the subcarriers used to record the colour signals were moved up to get the improved video bandwidth needed. probably the sound would still work, though you would have lost the stereo available later.
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I love how he is talking about being a tight-@ss with that big mantis microscope in the background.
Bare minimum... Suuuuuuuure :)
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Dave is a tightwad, he is an old FleaBay hounddog. Never pays retail for test equipment unless it comes as a buy one get one free special with a Fluke thrown in as a bonus. A lot is loaned or for review as well.
Would love to get the castoffs from that lab......
FE is another FleaBay buyer, he gets great bargains.
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Dave is a tightwad, he is an old FleaBay hounddog. Never pays retail for test equipment unless it comes as a buy one get one free special with a Fluke thrown in as a bonus. A lot is loaned or for review as well.
Retail?
New?
I don't understand these words...
I'd never buy a new mantis with my own money!
Dave.
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Bad ’80s flashback! Man, I hated working on those things! :) First real electronics job was working in a TV/VCR shop right about the time this thing was in it’s prime. I think camcorders were the first consumer product to really adopt SMD components. Of course, that thing looks positively spacious inside compared to an iPhone or whatever..
The opto thingy sticking up into the middle of the cassette is a dual infrared LED, which emits out to both sides. There are sensors on either side of the cassette housing, which are used to detect the transparent leader tape at the ends of the cassette, so the unit knows to shut off the motor and go into stop or rewind mode. Some of the sensors would get fooled into operation by ambient light when you had everything open on the bench, causing you to have to shade things with a hand or a empty tape box while testing.
A delay line is standard stuff here in former-NTSC-land. Used to delay the luminance component of the signal so it arrives at the output at the same time as the chroma signals, which must travel through more circuitry. In a PAL system, the delay period corresponds to exactly1 horizontal scan line (64 microseconds), to allow the decoder to invert the signal phase at the end of each line , hence Phase Alternation by Line, or PAL.
If you carefully open the delay line, you can see it is a piezoelectric device, propagating the signal through a quartz wafer.
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The other day (ok, about 2 years ago), I bought a JVC GR-C1 camera for about R250.00 including postage (about 30 AUD). I bought it on a Local Auction Site (bidorbuy.co.za)
It included the Case, Charger, Powersupply, Camera, Battery, and 3 VHS-C Casettes, which made it very heavy, so scored on the postage.
The thing still works well (even the NICAD Battery still holds a Charge).
Dave will love this - It is the same type of camera Marty used to video Doc in the Parking Lot (BTTF 1 http://www.totalrewind.org/cameras/C_GRC1.htm (http://www.totalrewind.org/cameras/C_GRC1.htm)), so now you know how old the camera is.
P
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I can't help but think that the autofocus system is similar to that used in rangefinder cameras. A system that uses paralax and lining up two ghosted images optically as you manually focus.
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I only used a big camera like this (the one I used recorded to full size VHS tapes) a couple of times and I really liked it. The heavy camera makes the image much more stable than the very light modern cameras. Also, after recording I could just store the VHS tape instead of first transferring the video to a computer (either fussing with compression or using a lot of space) and then recording it to LTO tape or other media (and hoping it lasts as long as the old VHS tape or just recording it to VHS so that I know it will last decades)
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Inspired by Dave, I just busted apart a 1992-vintage follow-on to the camera in this video, a CCD-TR61. Paid about US$3 or so in a thrift store. Essentially the same camera in a lot of ways, except condensed down to perhaps 1/4 the size. The level of integration is astonishingly tighter, given only a six-year gap in production. A few pics below.
Now, what can one do with such a tiny little CRT....
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I understood that NTSC was Not terribly satisfactory color.
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I understood that NTSC was Not terribly satisfactory color.
This is how the standards were defined where I worked:
NTSC - Never Twice the Same Colour
SECAM - System Essentially Contrary to the American Method
PAL - Peace At Last
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This attempt at political analysis of the various color standards is kind of amusing, as well...
http://punya.educ.msu.edu/amusings/politics.htm (http://punya.educ.msu.edu/amusings/politics.htm)
As if you didn't have enough acronyms I'm about to give you three more. They are NTSC, PAL, and SECAM. These acronyms refer to different television systems used around the world today. Here, in the United States, we use NTSC. NTSC was the first color television system--created in 1953. It was developed to be compatible with the earlier black and white system. Essentially, what NTSC allows is the addition of color to the existing transmission, while permitting black and white only receivers to be unaffected by the additional color information. Although newer televisions and improved broadcast transmission have obviated the need for some of these controls, the NTSC system requires color televisions to have hue and color intensity controls. With the hue control you can change the color of faces from red to blue to green and any color in between. With the intensity control you can remove all color (returning to a black and white picture), add a little tint of color, or make the color as garish as a comic book. The ability to control color is so great that NTSC is said to stand for Never Twice the Same Color. By contrast, the PAL system (used in most of Europe), offers only a color intensity control, while the SECAM system offers no color controls at all.
I have often found the differences in control offered by these three systems very interesting. While the developers of each system approached the problem of delivering a color television signals to the home in what they considered the "best" way possible, each approach embodies certain assumptions. The American way puts the most control in the hands of the consumer. It also embodies the assumption that errors in transmission might need correcting in the home. It has little confidence that the broadcaster and transmission channel can deliver the color that the producer intended. Indeed, it suggests that the consumer might even desire color different than even the producer intended, and gives them the means to achieve their desires.
On the other hand, the PAL system offers a single color intensity control. A PAL viewer can adjust the intensity of the color, but is stuck with the colors the producer chose or the broadcaster transmitted. Of course, one could say that PAL viewers need never worry about misadjusting the hue control. The designers of the PAL system had greater confidence in their ability to deliver the intended colors, and perhaps less confidence in the ability of consumers to adjust colors properly. Why should anyone want to watch green or blue faces?
The SECAM system, developed in France, offers no control of the color to the viewer. The SECAM system puts all control of color in the hands of the broadcaster. This represents the highest confidence in the ability of the broadcaster (central authority) to deliver the proper picture, and the lowest confidence in the ability of the consumer to adjust his or her own set. What is fascinating is which system each country of the world has chosen.
The rugged individualists of the United States have the ability to determine color to their heart's content. The more socialist democratic states of Europe and China have the ability to decide how much color to have, but the actual colors are determined by the broadcaster. In the eastern European countries, the broadcaster determines all of your color choices, thank you.
In all fairness, I should mention that while NTSC television sets have the knobs to fully manipulate the color, relatively few television viewers understand how to use the knobs. In the early days of color television (before the current, stable TVs of today), a mis-adjusted television set was very common. The viewer had the power to determine the color, but often failed to exercise it.
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On most Tv sets I find the following - Brightness, colour, contrast all set to max. I then adjust them to sane levels, and turn off the blowtorch shop display mode. After 10 minutes the people no longer have a headache from looking at the screen, and it does not light up the street outside through the curtains.
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On most Tv sets I find the following - Brightness, colour, contrast all set to max. I then adjust them to sane levels, and turn off the blowtorch shop display mode. After 10 minutes the people no longer have a headache from looking at the screen, and it does not light up the street outside through the curtains.
Until you come back a week later and find all the controls at max again, then you give up >:(
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This attempt at political analysis of the various color standards is kind of amusing, as well...
http://punya.educ.msu.edu/amusings/politics.htm (http://punya.educ.msu.edu/amusings/politics.htm)
As if you didn't have enough acronyms I'm about to give you three more. They are NTSC, PAL, and SECAM. These acronyms refer to different television systems used around the world today. Here, in the United States, we use NTSC. NTSC was the first color television system--created in 1953. It was developed to be compatible with the earlier black and white system. Essentially, what NTSC allows is the addition of color to the existing transmission, while permitting black and white only receivers to be unaffected by the additional color information. Although newer televisions and improved broadcast transmission have obviated the need for some of these controls, the NTSC system requires color televisions to have hue and color intensity controls. With the hue control you can change the color of faces from red to blue to green and any color in between. With the intensity control you can remove all color (returning to a black and white picture), add a little tint of color, or make the color as garish as a comic book. The ability to control color is so great that NTSC is said to stand for Never Twice the Same Color. By contrast, the PAL system (used in most of Europe), offers only a color intensity control, while the SECAM system offers no color controls at all.
I have often found the differences in control offered by these three systems very interesting. While the developers of each system approached the problem of delivering a color television signals to the home in what they considered the "best" way possible, each approach embodies certain assumptions. The American way puts the most control in the hands of the consumer. It also embodies the assumption that errors in transmission might need correcting in the home. It has little confidence that the broadcaster and transmission channel can deliver the color that the producer intended. Indeed, it suggests that the consumer might even desire color different than even the producer intended, and gives them the means to achieve their desires.
On the other hand, the PAL system offers a single color intensity control. A PAL viewer can adjust the intensity of the color, but is stuck with the colors the producer chose or the broadcaster transmitted. Of course, one could say that PAL viewers need never worry about misadjusting the hue control. The designers of the PAL system had greater confidence in their ability to deliver the intended colors, and perhaps less confidence in the ability of consumers to adjust colors properly. Why should anyone want to watch green or blue faces?
The SECAM system, developed in France, offers no control of the color to the viewer. The SECAM system puts all control of color in the hands of the broadcaster. This represents the highest confidence in the ability of the broadcaster (central authority) to deliver the proper picture, and the lowest confidence in the ability of the consumer to adjust his or her own set. What is fascinating is which system each country of the world has chosen.
The rugged individualists of the United States have the ability to determine color to their heart's content. The more socialist democratic states of Europe and China have the ability to decide how much color to have, but the actual colors are determined by the broadcaster. In the eastern European countries, the broadcaster determines all of your color choices, thank you.
In all fairness, I should mention that while NTSC television sets have the knobs to fully manipulate the color, relatively few television viewers understand how to use the knobs. In the early days of color television (before the current, stable TVs of today), a mis-adjusted television set was very common. The viewer had the power to determine the color, but often failed to exercise it.
Very strange, there is no limit to the consumers colour control built in to the PAL or SECAM systems it is up to the TV manufacturer to provide all the colour control he wants to the TV so the end user can tweak the colours all they want.
The only political aspect of TV systems I know of is that many eastern block countries chose the French SECAM system to make it more difficult receive the neighbouring western European broadcasts using PAL.
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The only thing choosing SECAM receivers would do however is receive monochrome PAL only, which is still good for propaganda. Unless it attempted to decode the colour, in which case you'd get a flickering mess of colour but still usable luminosity. (You could turn the colour intensity control down... oh, wait, you don't have it ;))
As someone who has designed the occasional video processor: Please, SECAM, die. You make everything so much more complicated. PAL and NTSC both QAM encode their colour, but no, SECAM has to use FM. Usually, I do not worry about adding SECAM support, as very few cameras and devices output it - but it does worry me that my system might not work with it if I produce something.
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NTSC - Never Twice the Same Colour
SECAM - System Essentially Contrary to the American Method
PAL - Peace At Last
And ATSC - Always Twice the Same Color...
Really, ATSC is great except they decided to use the oddball 8-VSB modulation that is both more expensive to demodulate and less reliable than OFDM. Also, they kept the crazy 59.94Hz framerate, which complicates the design of PLLs in video circuits and even worse, they backported it to Blu-ray for no good reason.
What I really hate about old video standards is interlacing, since it degrades image quality on modern displays. (I understand that it was a necessary evil back in the days.) For compatibility with old equipment, they should have just used interlaced half frames as a way to send progressive frames (standardizing the even/odd order), so deinterlacing would just be a matter of buffering.
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Then you got the VCR, which included autoswitching between SECAM and PAL as standard. NTSC needed a switch hidden in the front panel.
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What I really hate about old video standards is interlacing, since it degrades image quality on modern displays. (I understand that it was a necessary evil back in the days.) For compatibility with old equipment, they should have just used interlaced half frames as a way to send progressive frames (standardizing the even/odd order), so deinterlacing would just be a matter of buffering.
Properly deinterlaced (or viewed on a CRT SDTV) video is much smoother than progressive video at half the frame rate, but is a bit lower resolution. It is almost as good as progressive video at the same frame rate (50/60fps). My DV camera has a setting between 25fps progressive and 50Hz interlaced - on a SDTV (or a PC with good deinterlacing software) the interlaced video looks much better. I like the higher frame rate - it's good that the HD standard allows 50/60 fps progressive video - if only movies could be produced with that frame rate (at least those that are no longer produced on actual film).
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Dave, what part of the camera did the roach come from? I wonder if it might have been interfering in some way with the tape mechanism and once removed, the tape transport worked.
You've possibly mentioned this before, but what video camera are you using for your videos and what software are you using for video editing. They look to be doing a really excellent job.
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Properly deinterlaced (or viewed on a CRT SDTV) video is much smoother than progressive video at half the frame rate, but is a bit lower resolution. It is almost as good as progressive video at the same frame rate (50/60fps). My DV camera has a setting between 25fps progressive and 50Hz interlaced - on a SDTV (or a PC with good deinterlacing software) the interlaced video looks much better. I like the higher frame rate - it's good that the HD standard allows 50/60 fps progressive video - if only movies could be produced with that frame rate (at least those that are no longer produced on actual film).
How does it compare to recording at 25/30FPS progressive and motion adaptive interpolating to 50/60FPS progressive?
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How does it compare to recording at 25/30FPS progressive and motion adaptive interpolating to 50/60FPS progressive?
I do not know as I do not have a video processor that can do this.
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Dave, what part of the camera did the roach come from? I wonder if it might have been interfering in some way with the tape mechanism and once removed, the tape transport worked.
Didn't notice, it just fell out!
You've possibly mentioned this before, but what video camera are you using for your videos and what software are you using for video editing. They look to be doing a really excellent job.
Canon HF G10 with Opteka x10 macro lens for the close shots.
Sony Vegas MovieStudio Platinum 12, not that that really matters, a video editor is a video editor (unless you render incorrectly).
Dave.
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Canon HF G10 with Opteka x10 macro lens for the close shots.
No wonder the videos look so great. That's nice gear.
Sony Vegas MovieStudio Platinum 12, not that that really matters, a video editor is a video editor (unless you render incorrectly).
I asked because I knew that if you'd ever had problems with it, you would have certainly mentioned it. ;-) According to my reading of reviews on Amazon.com, too many editors appear to have PC hardware related issues.
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How does it compare to recording at 25/30FPS progressive and motion adaptive interpolating to 50/60FPS progressive?
I do not know as I do not have a video processor that can do this.
If you have a PC, you have a video processor that can do it and much more. :)
http://superuser.com/questions/224095/looking-for-temporal-upsampling-motion-interpolation-software (http://superuser.com/questions/224095/looking-for-temporal-upsampling-motion-interpolation-software)
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No wonder the videos look so great. That's nice gear.
The lens cost a whopping $30 or something :->
But yeah, the $1600 Canon is really good. Almost too good as I have mentioned in a video, to the point that it's depth of field and auto focus speed are a hindrance in this application.
Sony Vegas MovieStudio Platinum 12, not that that really matters, a video editor is a video editor (unless you render incorrectly).
I asked because I knew that if you'd ever had problems with it, you would have certainly mentioned it. ;-) According to my reading of reviews on Amazon.com, too many editors appear to have PC hardware related issues.
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Sony Vegas is the "lesser of the evils".
I used to use Ulead/Corel VideoStudio for a few hundred early videos. I have also used NCH VideoPad (Australian!), and a few others here and there.
They all have various advantages and disadvantages.
e.g.
VideoPad is glitchy with my Canon files
VideoStudio is slow with my new HD files and has render issues.
Vegas sucks arse on basic stuff like titling, pan/zoom, and transitions (all are fiddly) but you get used to it. It also sucks on rendering in not offering a constant quality variable bitrate, so I have output in a high fixed bitrate and then do a 2nd encode with another program (handbrake).
I settled on Vegas because it offers the best speed in editing playback and usability and doesn't seem to have any glitches.
NCH Video is the best for the type of work I need to do. i.e. not spend a month editing a hollywood feature, just throw together clips and render. But I can't stand the glitches in theo utput video, that is unacceptable. I do not have the time to watch the entire output video to make sure it's 100% correct.
Dave.
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Hi Dave.
Can you please tell me what kind of car monitor that is (21:20)? I could really use a small cheap display with composite video like that.
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Hi Dave.
Can you please tell me what kind of car monitor that is (21:20)? I could really use a small cheap display with composite video like that.
Car rearvision mirror reversing display, <$30 on ebay.
Dave.
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Dave!
Could you be so kind as to post a link to the Circuit Diagram you obtained.
Was it free or did you have to pay for it.
I am hacking some viewfinder CRTs and would like to see how they are wired up.
Thankyou :)