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#46
10-12-2019, 12:25 PM
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I think you're just not focused in on the right spot in the waveform. If that scope has delayed sweep, I'd try that. It combines the two time bases: you set the one to focus in on a small portion of the waveform you're looking at, then the other is used to add the delay time, which lets you scroll up and down the waveform looking for the bit you want.
Anyway, I'm enjoying reading this thread, it'll be useful to me when I finally get to working on my VR-1000.
__________________
The quality goes in, before the cat goes on!! 
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#47
10-12-2019, 11:23 PM
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The waveform you are getting looks like very distorted NTSC color bars to me (maybe clipped and inverted). Are you using NTSC color bars?
If so, maybe your fine tuning is off or you are actually tuned to the wrong channel. There is no color subcarrier showing, which could be caused by this. The scope vertical setting specified is curiously low, as .02 V/div would indicate about a 0.1 v p-p video signal is expected at TP A7. This may be correct (I don't know), but many video circuits use a video level around 1 V p-p.
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#48
10-13-2019, 10:44 AM
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Adam I think when I finally get this thing fixed I'll make a new thread with a step by step.
Also to both of you, as you can see the paper says horiz 10us div and vert .02v however it does not seem to show a useful waveform. I am also VERY new to scope and still do not fully understand how it works, so bear with me haha. As we know already the color is pretty shot on this unit, and I might be better waiting until the new crystal arrives. If you look at this picture, when i turn AFT off, the color bars coming into the VTR are way off. which may be affecting the signal. See attached image. (The color bars from a few posts back was posted with AFT turned on) Is there a way I can feed the NTSC signal right from the generator to the scope to use as a control?
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#49
10-13-2019, 10:53 AM
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Well, that picture seems to correspond somewhat to the waveform you are getting, so I'm guessing you are using the scope correctly.
If the tuning is that far off, the AFT may not be able to correct it at all. What channel is your generator output? Try setting the VCR tuner one channel higher or lower - you may be tuned to the wrong sideband of your generator. When the generator is set to channel 3, for example, it also produces a lower sideband with reversed spectrum on channel 2; when set to channel 4, it produces a lower sideband on channel 3. You can use the video output of your generator into the video input of your VCR and skip the tuner problems. Last edited by old_tv_nut; 10-13-2019 at 10:59 AM.
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#50
10-13-2019, 11:02 AM
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Correction to the above: I see the video (camera) input is a large connector, not RCA. I am struggling to recall the correct name for that connector. Anyway, you will need an adapter from that to BNC female, and a male-male BNC cable to connect to the generator.
Someone help with the correct designation for that connector please!
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#51
10-13-2019, 11:06 AM
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Quote:
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
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#52
10-14-2019, 12:13 AM
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Quote:
and Old_tv_nut. I cannot seem to find out what the connector is called. I've seem images of it, but no designation. EDIT: So I've found out it's called a SO-239. I've ordered a converter piece to F type coaxial so I can run the signal right into it bypassing the VHF UHF Last edited by starbond; 10-14-2019 at 08:19 AM.
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#53
10-14-2019, 11:18 AM
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I think it's this vintage microphone connector.
Note the data sheet below is for a female plug that supposedly can be converted to male, but I'm not totally confident it's the right thing, because they don't show the male configuration. You would have to solder this to the end of a coax cable yourself. An alternative would be to replace the obsolete connector on the VCR with a BNC jack. https://www.mouser.com/ProductDetail...caAufKEALw_wcB http://www.switchcraft.com/Specifica...spx?Parent=810
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#54
10-14-2019, 11:53 AM
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Quote:
 
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#55
10-14-2019, 12:54 PM
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Yes! Also found on old sweep generators.
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#56
10-14-2019, 01:08 PM
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The SO-259 aka UHF connector is what you want and IS different from a microphone connector.
The UHF connectors were typically found on pro and broadcast video gear into the early VCR era and is also very common on HAM radio and CB gear for the antenna connection. Mic connectors were found in audio mostly in the 30s-50s, and in test equipment like RF signal generators into the late 60s. Mic and UHF look similar in pictures but are different sized and not intercompatible... I've got enough gear to need both types of connectors and compare side by side.
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
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#57
10-14-2019, 09:37 PM
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Had one of these units long ago.. The video or camera in is the same connector as used on CB radio antenna connectors. and the microphone input uses the same plug as youd see on a guitar or standard microphone..
Stripped mine down when it quit. May stilll have parts lying around, not sure..  SR
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#58
10-14-2019, 10:26 PM
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Quote:
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#59
10-15-2019, 08:24 PM
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Been a long time since that quasar was here, but if i trip over a part or two, i promise ill give you a shout..
SR
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#60
10-18-2019, 08:22 AM
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Just a little update, my new 3.57mhz crystal came in, unfortuantely didnt not fix the color issues. however now the scope DOES show the correct NTSC waveform, so i did something right lol.
I think the next step is to check out the components on the color rec/ board.
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Linear Mode
