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-   -   Motorola ts907 low hv (http://www.videokarma.org/showthread.php?t=275174)

Electronic M 12-10-2022 11:50 PM

All you need for TV alignment on a "modern" 45 MHz IF like that is a B&K 415 and an oscilloscope about $50-100 if you shop around the right places.. IIRC the person who sold that set wanted like $250 for it... Another $100 for an alignment rig doesn't sound like a bad investment. I have an alignment rig just like I mentioned...I think the scope cost me $50 and the B&K cost me $25. I have been able to do a couple of alignments with it, but I'm still learning.

If you are going to screw around setting it by eye (that'll add another 200 pages to this mess easily) you should use a Philips PM-5544 test pattern (download a picture of one off the Google search, put it on a USB and use a media player that can display pictures from a USB on a TV). The PM-5544 has color bars and a multiburst pattern which gives a visual representation of the IF frequency response on screen...With that pattern you should be able to see if you are making things worse or better...If you can get it right by eye it'll be a small miracle.

Quote:

Originally Posted by dtvmcdonald (Post 3247050)
I disagree. It looks like very bad purity.

I had the same thought.
I think there were other pictures where the OP had more obvious real color in the pictures.

EDIT: ugh! Another stinking page.

Yamamaya42 12-11-2022 12:33 AM

correct, the purity is very bad, and Tron is a bad choice for a color example, but there IS color, weak as it is, red on the lips, and blue on the glowy but of the suit.
the set IS working enough to do a quick purity and convergence on it.


It's still highly suggested to build the video amp, and rig for A/V input until a future time that you have to tools to do the IF alignment.

timmy 12-11-2022 06:27 AM

Quote:

Originally Posted by Electronic M (Post 3247060)
All you need for TV alignment on a "modern" 45 MHz IF like that is a B&K 415 and an oscilloscope about $50-100 if you shop around the right places.. IIRC the person who sold that set wanted like $250 for it... Another $100 for an alignment rig doesn't sound like a bad investment. I have an alignment rig just like I mentioned...I think the scope cost me $50 and the B&K cost me $25. I have been able to do a couple of alignments with it, but I'm still learning.

If you are going to screw around setting it by eye (that'll add another 200 pages to this mess easily) you should use a Philips PM-5544 test pattern (download a picture of one off the Google search, put it on a USB and use a media player that can display pictures from a USB on a TV). The PM-5544 has color bars and a multiburst pattern which gives a visual representation of the IF frequency response on screen...With that pattern you should be able to see if you are making things worse or better...If you can get it right by eye it'll be a small miracle.



I had the same thought.
I think there were other pictures where the OP had more obvious real color in the pictures.

EDIT: ugh! Another stinking page.

If I can get that test pattern on a dvd I can plug the dvd into one of those modulators then cable wire from modulator to tv antenna input using the matching transformer that should work.

Yamamaya42 12-11-2022 09:24 AM

you have the RCA pattern generator, does it not work?
http://www.videokarma.org/attachment...7&d=1648416460


and it's pretty certain that you can't align the IF visually, 95% chance of making it worse each time you try.

timmy 12-11-2022 10:31 AM

Quote:

Originally Posted by Yamamaya42 (Post 3247064)
you have the RCA pattern generator, does it not work?
http://www.videokarma.org/attachment...7&d=1648416460


and it's pretty certain that you can't align the IF visually, 95% chance of making it worse each time you try.

Yes I have the same rca generator and works great

timmy 12-11-2022 11:01 AM

Was able to set up the color and purity convergence made sure hv was 24kv this pick is a dvd test point B and degauss

timmy 12-11-2022 11:19 AM

Don’t really understand why this works when the IF is messed up is it because I have B&W video already

Yamamaya42 12-11-2022 11:55 AM

Live video is very different from a still static non moving image.
As others have mentioned, when you fine tune the set, if you get color shifting especially in the reds, it's a sign that the IF is out of alignment, and it is not unusual for it to be able to lock with a test pattern and not a live video.

zeno 12-11-2022 02:49 PM

UNLESS its the camera the live pix is TOO DAMN BRITE !!!
The set is still on its side also. If it is in reality when you get it
back on its feet you will need to re do the set up.
You should be able to turn the color, brite & contrast down & extinguish
the raster or nearly so. These sets were NOT brite ! In the day most
watched them in a darkend room with curtains drawn.
This is NOT a Chromacolor, Trinitron, EFL or FTM CRT that you could light
a room with. If you overdue the brite everything starts to fall apart pix wise

As for generators we did 90% of our set ups were by eye. Live shows worked
better for us & give a real world look at the pix. Try it. No confusing mirror,
just lay across the set, look at pix & reach back to adj. SO much easier.
Also generators can add problems if the TV's controls are not set right.

One last thing. Put up a pix of the set with NO signal, just snow. Snow
can tell you a lot believe it or not.

73 Zeno :smoke:

Electronic M 12-11-2022 03:07 PM

Quote:

Originally Posted by timmy (Post 3247067)
Don’t really understand why this works when the IF is messed up is it because I have B&W video already

If that test pattern is coming through the tuner/IF then there's plenty of hope those circuits will pass color from a normal program.

Test pattern generators RF output isn't always consistent with a normal RF modulator used for watching videos. That test pattern generator probably has a composite video output. I would try hooking the composite video output of the test pattern generator to the composite video input of whatever RF modulator you use to feed program material to your sets (if the composite video output of the generator is variable level use a different known working TV fed by your RF modulator to set generator video level). Then I'd feed the output of your RF modulator into the TV and see if I could optimize color through the TVs tuner by playing with fine-tuning and color level...If you can get a color test pattern from your generator through the RF modulator you use for DVDs and TV watching, through the Motorola's tuner and looking good on screen then you should be able to get color from a normal TV program on screen.... Whether alignment is good enough to pass good monochrome and or sound at the same time remains to be seen...
One reason I don't like gated rainbow generators like that is that while they give you a good color pattern that's all they can do while displaying color. That Philips pattern I mentioned shows you color response and accuracy, monochrome response, gives a good method of checking sweep linearity, and several other things...When you potentially have multiple issues in a picture and they may all be interrelated to varying degrees that pattern is a helps making adjustments that are the metaphorical walking and chewing bubble gum/rubbing your head scratching your belly...It let's you see clearly how all the picture systems that could be having issues are doing all at the same time while your messing with things.

Yamamaya42 12-11-2022 03:15 PM

Quote:

Originally Posted by zeno (Post 3247071)
UNLESS its the camera the live pix is TOO DAMN BRITE !!!
The set is still on its side also. If it is in reality when you get it
back on its feet you will need to re do the set up.
You should be able to turn the color, brite & contrast down & extinguish
the raster or nearly so. These sets were NOT brite ! In the day most
watched them in a darkend room with curtains drawn.
This is NOT a Chromacolor, Trinitron, EFL or FTM CRT that you could light
a room with. If you overdue the brite everything starts to fall apart pix wise

As for generators we did 90% of our set ups were by eye. Live shows worked
better for us & give a real world look at the pix. Try it. No confusing mirror,
just lay across the set, look at pix & reach back to adj. SO much easier.
Also generators can add problems if the TV's controls are not set right.

One last thing. Put up a pix of the set with NO signal, just snow. Snow
can tell you a lot believe it or not.

73 Zeno :smoke:

the live pic looks crappy because the input video being fed to test point B is 4-5 times too low, the TV expects 5v PtP going into the 1st video amp, but w/o an amp to boost it, it is only getting 1v, and will have a washed out picture when fed direct video to that point no matter the brightness level setting.

And the reason the set is on it's side is that it has the access panel removed on the bottom to reach the underside easily for service with the chassis still installed.
It's prob petty much understood that once the set is upright and in it's final location, a final purity and convergence will need to be done again, as is always with these sets.

timmy 12-11-2022 03:30 PM

Quote:

Originally Posted by Yamamaya42 (Post 3247073)
the live pic looks crappy because the input video being fed to test point B is 4-5 times too low, the TV expects 5v PtP going into the 1st video amp, but w/o an amp to boost it, it is only getting 1v, and will have a washed out picture when fed direct video to that point no matter the brightness level setting.

And the reason the set is on it's side is that it has the access panel removed on the bottom to reach the underside easily for service with the chassis still installed.
It's prob petty much understood that once the set is upright and in it's final location, a final purity and convergence will need to be done again, as is always with these sets.

Yes that’s right about how the pic looks and the set is on all 4 legs. Overall the pic looks good considering all these problems with this set colors look better then previous pics.

Yamamaya42 12-11-2022 03:32 PM

This is what got color working on my CTC-16XL, however, my set is quite a different situation than yours and there is absolutely no guarantee that this will help you at all, but it can't make it worse like trying to mess with the IF transformers, try adjusting the 4.5 mhz trap, A13, this in the only one done visually, get a decent BW video, contrast at max, turn up color to where you see the herringbone pattern, and then tune 4.5 mhz trap, A13 to see if it makes any changes at all, if it does not put it back, mine was WAY off and I had to adjust it many turns, but this may not be the same for you.

timmy 12-11-2022 03:37 PM

As for snow the screen is all white and has the normal snow and the sound has snow as well changing the channel changes the snow alittle.

timmy 12-11-2022 03:43 PM

Quote:

Originally Posted by Yamamaya42 (Post 3247076)
This is what got color working on my CTC-16XL, however, my set is quite a different situation than yours and there is absolutely no guarantee that this will help you at all, but it can't make it worse like trying to mess with the IF transformers, try adjusting the 4.5 mhz trap, A13, this in the only one done visually, get a decent BW video, contrast at max, turn up color to where you see the herringbone pattern, and then tune 4.5 mhz trap, A13 to see if it makes any changes at all, if it does not put it back, mine was WAY off and I had to adjust it many turns, but this may not be the same for you.

There’s no trap at a13 are you talking about a3 that’s where the 47.25 trap is I haven’t touched that one afraid it’s going to do what the other trap did but when I stand it up again I’ll try that.


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