Motorola ts907 low hv

[dtvmcdonald]

Originally Posted by timmy

But if I was to get that pattern perfect color wise does that mean color in video would be good also.

Probably, assuming the video connection was done correctly.

[Electronic M]

Originally Posted by timmy

I got the color pattern to help assist, it was tough to tune it in but I did but regular tv has color bars just waiting to drop on to a picture . this IF business really sucks trial and error but the pattern started out with no color at all. Using a dvd with an rf modulator to the antenna terminals this is what I was able to get after adjusting but how much different is the antenna signal compared to the dvd signal.

If you can adjust the diagonal noise away with fine tuning and retain enough color signal you may be able to get away with tweaking the hue/tint control and if that isn't enough eyeballing the color demod transformer...I've had to do the old demod eyeball adjustment on my CTC-4s it's not that hard....Granted if that test pattern looks perfect hue wise with video injection (haven't seen that checked yet), but looks terrible through the IF then that would be an IF alignment issue.

[timmy]

Originally Posted by Electronic M

If you can adjust the diagonal noise away with fine tuning and retain enough color signal you may be able to get away with tweaking the hue/tint control and if that isn't enough eyeballing the color demod transformer...I've had to do the old demod eyeball adjustment on my CTC-4s it's not that hard....Granted if that test pattern looks perfect hue wise with video injection (haven't seen that checked yet), but looks terrible through the IF then that would be an IF alignment issue.

Well it is an IF alignment issue so I’m passing time screwing around with all 3 cans since it’s messed up already I have nothing to lose. But I was able to get all colors for the first time on this pattern but it looked like fine tuning it would clear it up but then lost the color lock on the colors so it appears it’s close

[Electronic M]

Originally Posted by timmy

Well it is an IF alignment issue so I’m passing time screwing around with all 3 cans since it’s messed up already I have nothing to lose. But I was able to get all colors for the first time on this pattern but it looked like fine tuning it would clear it up but then lost the color lock on the colors so it appears it’s close

Maybe all it needs is a tweak to the color osc. I typically take a fully saturated color bar pattern, crank color level to max, set fine tuning to the weakest signal level where I can still make out the barberpoling then adjust the color osc to sync. If you can rock the channel knob and not loose sync with the fine tuning at the edge of passing color then you'll never loose color lock on normal content.

[timmy]

Originally Posted by Electronic M

Maybe all it needs is a tweak to the color osc. I typically take a fully saturated color bar pattern, crank color level to max, set fine tuning to the weakest signal level where I can still make out the barberpoling then adjust the color osc to sync. If you can rock the channel knob and not loose sync with the fine tuning at the edge of passing color then you'll never loose color lock on normal content.

I seem to get all the colors in there place on the pattern except for red it shows up in the wrong place while others are right on. And trying to adjust this I don’t know if I should have the color up and the tint control up these 2 things could add to the difficulty in trying to get the color right.

[Electronic M]

If all you are doing is setting the tint/hue you want color level to be fairly low. If you have color level too high and overdrive the demodulator you'll get distortion in the demodulate hue...It's also important to have purity good before trying to watch or adjust color...I once drove myself mad for a few hours trying to figure out why the yellow bar on a SMPTE color bar pattern was wrong on a Zenith despite all other bars being right....After chasing my tail I gave up and dialed in the purity and suddenly yellow was as perfect as all the other bars.

[timmy]

The red is not where it should be but the pic is better then the last one. Purity is good got white screen.

[Electronic M]

Originally Posted by timmy

The red is not where it should be but the pic is better then the last one. Purity is good got white screen.

Besides the diagonal interference it looks good to me. The magenta/red aren't perfect, but I've watched worse.

[timmy]

Originally Posted by Electronic M

Besides the diagonal interference it looks good to me. The magenta/red aren't perfect, but I've watched worse.

Well I got it even better but tv video only has color lines running across the screen it’s not locking in.

[timmy]

This is a running video fed to the antenna input of the tv why is the video playing with perfect color but I put the cable wire on and this is what I get. What is the difference between the dvd and rf modulator and cable.

[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.

[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.