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  #136  
Old 09-21-2016, 10:12 AM
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y'know I checked my probe before I started probing. Just checked it again, sure enough the little switch was on 10x... must have slipped while contorting my hand to hold the probe on some pin at some point. Today has not been going my way so far lol
As a general rule, you always want to use the probe in 10x mode unless you need to look at a signal that's too small to see in 10x mode. In 10x mode it loads down the circuit less and helps protect the scope from over voltage damage. Also, the bandwidth in 1X mode is generally very low.
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  #137  
Old 09-22-2016, 01:39 PM
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Ahhhh, that'll help with the loading problems I've been seeing when I probe stuff! I figured that was the problem but it never occurred to me to solve it that way.
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  #138  
Old 09-23-2016, 12:41 AM
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heh that's etype2's site, as seen in other posts in this thread
OK I did not know that .Thanks etype2 for wealth of info on your website.
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  #139  
Old 07-14-2017, 04:56 PM
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Andy recapped and cleaned the circuit boards on my two Sony KVX 370 Indextrons more then 7 1/2 years ago. Both are still running strong as the day he returned then to me.

We decided to do a couple of videos to show what they look like operating. I don't think anyone has done that in the forums so far. I've done videos on conventional three gun color sets and have not encountered the scan problem seen in these two videos. Different scan rate? Not sure.

In this link, the top two videos show one of my two Indextrons. Choose the HD setting, otherwise you will see low quality video. https://m.youtube.com/channel/UCejCrh3g0-hsYCG63RHNyYA

(Some might say the Indextrons produce cr*p video anyway) :-)
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Last edited by etype2; 07-14-2017 at 05:32 PM. Reason: Typo
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  #140  
Old 07-14-2017, 05:51 PM
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Two things contributing to the dark bars:
1) Whatever your camera is, it's running at 60.00 Hz (or 30.00) instead of NTSC 59.94 Hz (or 29.97). This causes the bars to drift vertically.
2) The shutter duration is too narrow. If there is no direct shutter control on your camera, you could try reducing the brightness of the TV to get the camera to lengthen the shutter time
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  #141  
Old 07-14-2017, 09:05 PM
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It's a iPad Pro 10.5. I have the ability to take it out of auto and set exposure and focus. We almost always take screenshots manually including videos. We touch and hold the LCD screen in the center of the video image and the camera reads the light of that point and locks the focus and exposure. It gives the best results. By doing this it darkens the surroundings.

For some reason, only on the one gun Indextron, we see this dark slow scan on videos and on screenshots, it's hit and miss. I can't see it on the LCD but the shot will come out dark in a portion and correctly exposed as to the remainder. Other shots will be fine, but I have to do multiple shots to be sure I catch a full exposed image. This only happens with an Indextron. Only one electron beam scanning instead of three must have something to do with it.

The frame rate for the two videos is 29.75 at 1/30 second. 4K
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  #142  
Old 07-14-2017, 09:17 PM
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Quote:
Originally Posted by etype2 View Post
We touch and hold the LCD screen in the center of the video image and the camera reads the light of that point and locks the focus and exposure. It gives the best results. By doing this it darkens the surroundings.
This is a good procedure for getting an exposure that is correct for the image, no matter how bright or dim. Since it should give correct exposure of the picture for all cases (by adjusting shutter duration), you should be able to do a quick experiment by setting the Indextron for a dim picture and see if this causes the iPad to expand the shutter time.
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  #143  
Old 07-14-2017, 09:24 PM
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I will try that and see what we get. Thanks.

*As you may know, The Indextron suffers from low contrast because the photo cell needs to detect enough light to send a feedback signal and it can't be set to absolute black. This problem however was ameliorated in the larger Sony IDX 5000 Indextron.

By turning down the brightness the image will look washed out.
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Last edited by etype2; 07-14-2017 at 09:33 PM.
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  #144  
Old 07-14-2017, 09:31 PM
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NEVER have understood -which was USU AWHY they went off on such aly a costly & ultimately highly wasteful item.
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  #145  
Old 07-14-2017, 09:36 PM
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I will try that and see what we get. Thanks.
Hope it works - looking forward to your report. No telling for sure what an automated video camera will decide to do.
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  #146  
Old 07-14-2017, 09:41 PM
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NEVER have understood -which was USU AWHY they went off on such aly a costly & ultimately highly wasteful item.
It's all about the technology. The idea that a full color image can be produced from a single electron beam instead of three fascinates me. As a result no need for convergence control, simple circuits, etc.

I will be posting a video of the Sony IDX 5000 Indextron which has a bigger screen, much improved contrast and resolution. The phosphor and index stripes are of a finer pitch. It's so bright it hurts your eyes when it's turned on because it produces a brief white screen during power up.
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  #147  
Old 07-14-2017, 09:46 PM
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You also have to realize that this was during the time when Japanese TV companies were flush with cash and dozens of hired-for-life engineers who needed something to occupy them - so projects that an American company would study on paper and reject at that point were carried through by the Japanese to sometimes very costly prototype / limited production.
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  #148  
Old 07-14-2017, 09:51 PM
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"No telling for sure what an automated video camera will decide to do."�� :-)

Also it was a time when TFT LCD color televisions were already invented. The Indextron would not have survived, but I'm convinced that the Indextron could have been developed to be superior to the Trinitron if circumstances permitted.
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  #149  
Old 07-14-2017, 09:54 PM
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Another note regarding the background gray level needed for the indexing to work. Plasma panels had a similar problem at first, but ways were found to reduce the unwanted "fog" as time went by. It's quite possible that Indextron design could eventually have been improved incrementally to a point where it was acceptable compared to a shadow mask CRT too, but it died before enough effort could be concentrated on it.
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  #150  
Old 07-15-2017, 09:46 AM
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Usually, 2 or 3 times a year, we'll have a Snot-Slingin'Thunderstorm roll thru here. Adios ,passwords !Then, Uncle Sandy has to go back, & try to get the miserable machine to accept the password that was Hunky-Dory last night, but VERBOTEN now..I kinda think it does this just to SPITE me...
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