dvd - stinking retrace lines

[AudioMixer]

Hi Charlie, I didn't look at it that way, I just got over my head when I replied.
You're right, like everything we vintage guys like to do with our toys. Again . you're correct - it's been a LONG time since I saw with my own eyes the sets from our past. I bet Walter Cronkite would look great in all of the members restored set's I've seeing on this forum. In fact, I own the Apollo launches of our space program when we were sending men to the moon Walter Cronkite's original CBS NEWS broadcast of Apollos 7 thru 14 with their original commericals - Western Electric. Apollos 15 thru Skylab launch was NBC NEWS with Frank McGee all on DVD as I transfered them from VHS tapes.






[QUOTE=Charlie]I realize you directed this question at Frenchy, but you might not yet realize that nearly everyone in these vintage television forums does the same thing- connecting DVD's, VCR's, Laser Disc, Satellite Boxes, or anything else to these sets. Of course, we do this so we can watch them like any other set. No, they do not produce the resolution of HDTV, but if you have one of them tuned well, they will produce a picture just as good as any standard tv. For some of us (such as myself), we play these sets as daily watchers.

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[vintagecollect]

What IS the fix for retrace lines???





Can someone post this please for us. Awesome screen Charlie!!




These roundies have same picture size as a 27" rectangle screen, with corners taken off. Since these are classic large screen TVs, DVD still deliver the best possible resolution, sharpest picture available on these old sets.


Great to see full potential of screen quality without degrading qualities of videotape or cable signal(less than perfect signal), also cable company has annoying buzzing sound through speaker sometimes or any snow/interferance with antenna signal. Please post repair for retrace lines, ruins an otherwise perfect viewing experience, definetlty takes away from watching show.

[Charlie]

Ya know, it just occurred to me that I do not get the retrace lines on my Curtis Mathes roundie. They don't seem to reach the picture. I have the height set just barely beyond the mask as it should be, but I still don't get them. I know they're there because if I fool with the verticle hold, I'll see just a trace of them... perhaps 1/8 of an inch. This goes for protected DVDs as well as occassional lines from broadcasts.

I DO get them on my CTC15... they extend about 2 or 3 inches from the top. They are quite strong. Very annoying, but I've gotten used to them.

It makes me wonder what can be different between the two sets. The chassis are very similar. The CM chassis seems to be a cross between a 15 and 16.

[old_tv_nut]

Has to be a difference in the vertical blanking pulse. I get the lines in my 67 Magnavox, and I've just been putting up with it.

[vintagecollect]

I get these on all of my roundies. One roundie has 4 to 6 of these lines!! So there's no fix, even an engineering tweak???

[Adam]

I really second your distaste for these lines, I have several sets of DVDs I would really like to watch retrace-line free on my roundie or even one of my early rectangular color sets, or B&Ws.
I liked the idea of having some device between the DVD player and the set that could do that, that way you could use any combination of player and TV. I would think that modifications could be made to an ordinary RF modualtor, which we all have to use anyway, to just cut off the video signal during retrace. I don't think it would have to be done in the set as the video signal itself contains those sync pulses, couldn't the vertical ones somehow be used to trigger something that would cut off the video amplifier contained in the RF modulator at regular intervals corresponding to the retrace? I don't really know, while I can imagine that such a device might be possible, figuring out exactly how it would work requires much greater knowledge than I posess.

[vintagecollect]

I'm saying this because its true, I a have a CTC-5 tv and a RCA CTC-36 color TV (one of RCA's last color tube chassis). Both display retrace lines prominantly. This IS quite a spread in RCA models, still both quite similiar in design too. Fair amount of AKers with RCA tube color sets, I'm gonna start trying various patches, will post any sucess found.

I have just noticed TWO DVD movies that Showed NO RETRACE LINES at all duriing playback.

[Adam]

I just read over all of this more carefully, and there were several solutions already posted. They basically fell into two categories: some DVD players allow this to be turned off, and some devices already exist that actually do manage to remove this from the video signal (but not all of these work well).
Unfortunately, none of these are particularly cheap options, unless you already have one of the players on that list.
About half of the DVDs I have don't give me the retrace lines, so I guess this means that they just don't have the copy protection, but there doesn't seem to be a way to tell this in advance, without actually playing it.

[Charlie]

True... some DVD's do not have the copy protection and you won't get the retrace lines. Usually, the recent movies will. If you happen to already have a DVD burner drive in your PC, you can copy them and leave the copy protection files off. Kinda funny to think though... they put that in there to keep from copying them... however you still can make a copy.

Many of the DVD's we have on board our ship are burned by the second mate. We play them in a cable system we built using several DVD and VHS players. Our player is a Panasonic, and it plays the burned copies just fine.

The mate also made copies of certain movie I wanted. When I brought them home, they played here on my roundie with no lines. I will probably be shopping around for an external burner soon to use here.

[veg-o-matic]

Well, so what do you do if you get retrace lines even if you're not watching a DVD? My Sylvania consistently shows what I think are retrace lines whenever the screen goes to grey. They don't show up with a color picture on screen.

veg

[Charlie]

Veg, do you know the condition of your CRT? If the tube is a little weak, and your screen controls and bias switch are set to compinsate for a weak tube, you'll likely have those lines. They can also show up simply from having the brightness too high.

[veg-o-matic]

Charlie, you hit the nail right on the head. I think the bias control is cranked up all the way. That'll do it, huh?
Would it be better to leave the bias set high or to lower it and stick a brightener on the tube? Or would that even do the same thing?
I know it's not the original tube; it's an RCA replacement. Boy, that set musta got watched a LOT!

veg

[Chad Hauris]

I have gotten the retrace lines if the screens are set too high. Try turning down the screen controls and turning up the brightness.

You can often rejuvenate a slightly weak tube by giving it boosted filament voltage just for a few minutes. I have put switches on some sets for boosted or normal fil voltage, just giving it a boost every now and again seems to help the CRT. In a transistorized set you can wind wire around the flyback core to provide the boosted voltage but on a tube set an actual filament trans should be used to prevent overloading the flyback. You could also modify a booster to add in a switch providing normal or boosted voltage. Keeping the switch at "normal" most of the time helps preserve CRT life over offering it the 8 volt boost voltage all the time.

[Adam]

Would upping the filament voltage on a 7JP4 electrostatic tube make it any brighter? I've been considering putting an 8v filament transformer to the 7JP4 in my Motorola for some time, but avoiding it as I was worried it might damage the tube in some unforseen way.

[jpdylon]

I'm not sure about the 7jp4 in particular, but filaments are 100% overrated, and will burn safely up to 12 volts. I would step it up to 8 volts with a seperate transformer and see what results you get. However if the motorola has the crt in series with the rest of the tubes, you will need to find the appropriate load resistance to keep the rest of the tubes in balance or you'll toast some tube filaments