Motorola ts907 low hv

[timmy]

Originally Posted by Electronic M

It's possible your DVD has higher color level on it's output and is overdriving the demodulator in the TV.

The main difference I see between the last 2 pictures is loss of color sync (barberpoling) in the second picture.
You fix babrberp the way I described earlier by adjusting the chroma osc transformer with a color bars test pattern and color level maxed and fine tuning set for the worst position that gives recognizable color/barberpoling, and adjust color osc to achieve sync under that worst case scenario so that it syncs very easily under better fine-tuning/signal conditions.

All the adjustments I did was in the IF transformers v1 2 and 3 to get to where I am now with the color picture which was a running video and that test pattern so I want to be careful and sure about turning other things turning the IF adjustments was bad enough. The color level on the tv is set really low. I’ll have to check the sams for which trans is. Which coil is it A17 or A18 one says chroma reference osc the other is chroma reference osc control.

[timmy]

Don’t know how far to turn the slug in the osc but can’t detune to get those lines color gets brighter then snow tried turn the slug with cable hooked up but the slug is really tight was able to move alittle back and forth no change. Could there be a problem with the 3.58 crystal where it would work for the dvd but not cable signal

[Yamamaya42]

Originally Posted by timmy

Don’t know how far to turn the slug in the osc but can’t detune to get those lines color gets brighter then snow tried turn the slug with cable hooked up but the slug is really tight was able to move alittle back and forth no change. Could there be a problem with the 3.58 crystal where it would work for the dvd but not cable signal

if you can't get it to lock with just slight tuning of the osc coil, it is more likely not a osc sync problem, and more related to the IF response curve.

[timmy]

Originally Posted by Yamamaya42

if you can't get it to lock with just slight tuning of the osc coil, it is more likely not a osc sync problem, and more related to the IF response curve.

Ok but I don’t understand how a video can play as good as it does and yet won’t Except the cable line what is the big difference between cable rf and dvd- rf modulator. How much should this slug be turned maybe I didn’t turn it enough.

[Yamamaya42]

Originally Posted by timmy

Ok but I don’t understand how a video can play as good as it does and yet won’t Except the cable line what is the big difference between cable rf and dvd- rf modulator. How much should this slug be turned maybe I didn’t turn it enough.

once you set the color sync with any given source, be, be it a color bar generator, DVD, or what ever, you should NOT have to change it again. the fact that it is still giving problems is an indication that the IF is still off alignment.

[timmy]

Originally Posted by Yamamaya42

once you set the color sync with any given source, be, be it a color bar generator, DVD, or what ever, you should NOT have to change it again. the fact that it is still giving problems is an indication that the IF is still off alignment.

Well I feel it can’t be that far off being if cable worked the dvd would work to but right now it’s just the dvd. Back to the dread. The colors on that pattern is still off alittle so if I get that pattern perfect maybe then it will be good on cable

[Electronic M]

Originally Posted by timmy

Ok but I don’t understand how a video can play as good as it does and yet won’t Except the cable line what is the big difference between cable rf and dvd- rf modulator. How much should this slug be turned maybe I didn’t turn it enough.

Unless the modulator on the cable box is the same brand and model as the one on the DVD player there's no guarantee it will perform the same or even try to implement the NTSC standard to the same level of strictness or laxness. Consumer gear isn't broadcast gear so it doesn't all try to implement NTSC to broadcast standards....It usually does the minimum to not get a lawsuit or excessive customer complaints...How far (if at all) beyond that "don't sue me" threshold a maker goes is their discretion.

Does the cable box have a composite video and audio out? If it does why not connect that to the modulator you use for the DVD player if that modulator works better. If all the cable box has is RF and HDMI use a either a VCR to convert the RF to audio and composite video for the modulator or an HDMI to AV converter.
Analog composite audio video switch boxes are cheap at the thrifts if you need to have multiple video sources feeding the modulator.

[timmy]

Originally Posted by Electronic M

Unless the modulator on the cable box is the same brand and model as the one on the DVD player there's no guarantee it will perform the same or even try to implement the NTSC standard to the same level of strictness or laxness. Consumer gear isn't broadcast gear so it doesn't all try to implement NTSC to broadcast standards....It usually does the minimum to not get a lawsuit or excessive customer complaints...How far (if at all) beyond that "don't sue me" threshold a maker goes is their discretion.

Does the cable box have a composite video and audio out? If it does why not connect that to the modulator you use for the DVD player if that modulator works better. If all the cable box has is RF and HDMI use a either a VCR to convert the RF to audio and composite video for the modulator or an HDMI to AV converter.
Analog composite audio video switch boxes are cheap at the thrifts if you need to have multiple video sources feeding the modulator.

So what it comes down to is the IF strip is out of alignment.

[timmy]

Ok so I understand that the cable boxes are digital now so to try to rule this out I need to find an RF modulator that is for old TV sets where it has cable in and the correct signal out for an old tv I guess an analog signal. Does anyone know what they are called or where I can get one. Years back it was on the news warning people the signal was changing and there tvs won’t work.

[old_tv_nut]

You say all your black and white sets work fine. Those sets are analog. So, whatever you are plugging into the antenna terminals of those sets should work with your analog color set.

When you are describing the hookup, please be specific and step by step, like:
1. coax from wall to cable box.
2. cable box output (say what it is called on the box) to coax cable to matching transformer
3. matching transformer to TV antenna screw terminals

[timmy]

Originally Posted by old_tv_nut

You say all your black and white sets work fine. Those sets are analog. So, whatever you are plugging into the antenna terminals of those sets should work with your analog color set.

When you are describing the hookup, please be specific and step by step, like:
1. coax from wall to cable box.
2. cable box output (say what it is called on the box) to coax cable to matching transformer
3. matching transformer to TV antenna screw terminals

Ok when I got cable I realized that there is no cable out just HDMI I could have just plugged it into the flat tv but I needed to get signal to my other TV sets so I did with 2 small units HDMI plugs into from the cable box and changed it to I guess the analog signal and that’s what I use to run my old sets with a few splitters. So ok then it’s not the cable signal but rather the tv IF must still be out enough not lock in color but yet the IF accepts the signal from a DVD player using a modulator for games and DVD players.

[Yamamaya42]

Originally Posted by timmy

Ok when I got cable I realized that there is no cable out just HDMI I could have just plugged it into the flat tv but I needed to get signal to my other TV sets so I did with 2 small units HDMI plugs into from the cable box and changed it to I guess the analog signal and that’s what I use to run my old sets with a few splitters. So ok then it’s not the cable signal but rather the tv IF must still be out enough not lock in color but yet the IF accepts the signal from a DVD player using a modulator for games and DVD players.

Wait a sec...
HDMI output only?
are you using something like this?
https://www.amazon.com/GANA-Composit...ct_top?ie=UTF8

something like this will NEVER work on vintage TVs I have tried, they are JUNK
you will get NO color or barber pole effect due to the sloppy colorburst it puts out, solid state TVs work MOST of the time, but tube, NEVER will.
you must have a Cable box that outputs composite video (ntsc) for it to work correctly

[Electronic M]

Originally Posted by Yamamaya42

Wait a sec...
HDMI output only?
are you using something like this?
https://www.amazon.com/GANA-Composit...ct_top?ie=UTF8

something like this will NEVER work on vintage TVs I have tried, they are JUNK
you will get NO color or barber pole effect due to the sloppy colorburst it puts out, solid state TVs work MOST of the time, but tube, NEVER will.
you must have a Cable box that outputs composite video (ntsc) for it to work correctly

+1. I've had mixed luck with those. I've had that same box with a couple different brands on it. First one worked great for a few months (of occasional use) then lost video completely, the replacement would get and loose color randomly and have other issues.

I've got an older metal box HDMI to AV adapter that's out of production that works better. Though my go-to is an HDMI to ATSC transmitter and a DTV converter box for my tube sets...It's expensive but gives me the best quality and aspect ratio control I've been able to get from HDMI sources.
This video gives an overview of that stuff. https://m.youtube.com/watch?v=hKjt3x4WtWU

[Yamamaya42]

Originally Posted by Electronic M

+1. I've had mixed luck with those. I've had that same box with a couple different brands on it. First one worked great for a few months (of occasional use) then lost video completely, the replacement would get and loose color randomly and have other issues.

I've got an older metal box HDMI to AV adapter that's out of production that works better. Though my go-to is an HDMI to ATSC transmitter and a DTV converter box for my tube sets...It's expensive but gives me the best quality and aspect ratio control I've been able to get from HDMI sources.
This video gives an overview of that stuff. https://m.youtube.com/watch?v=hKjt3x4WtWU

but it's pretty clear that the HDMI to AV adapter is the source of the color problem, Timmy has the same as I had, looks the same, I spent over 2 hours screwing with it and color never worked on the stupid thing, so it was thrown in the garbage.
the review i left for it
VERY poor quality.
But that is not surprising for the amount spent on the unit, I was hoping it might work, but like many others who got it, I was disappointed.
I got this unit to try to convert HDMI to composite for a vintage TV, if you are expecting black and white only, then this may work for you, but if you want color, get something of better quality, because the colorburst freq this puts out is WAY OFF, meaning that any vintage equipment can't lock on meaning NO COLOR at all, or barberpoleing if it tries to lock in color.
The only way to get this to work correctly is to run it through a time base corrector to correct the colorburst phase errors and get TRUE NTSC color out of it, which makes getting the thing rather pointless.
Bottom line, get something better.

[timmy]

This picture is what I’m using to run my flat tv but then I put a splitter in and one goes to the flat tv and the other to my b&w sets. How and what do you use for your color sets if you have a HDMI box output only. What do I have to do or buy to get the correct signal to this tv.