dvd - stinking retrace lines

[Chad Hauris]

I think using 8v on the filament for short periods of time every now and again can help "wake up" a tube that is going weak. It seems like the improvement would last for a week or so before needing to do it again. If the effect does not seem to last after returning to regular fil voltage then you could just leave it on the 8 volts all the time but this will make a filament burn-out more likely.
It should work on the electrostatic tube but I am not sure how rare of a tube this is so be careful if it is hard to replace.
One very gentle technique involves using a variable transformer ahead of a filament transformer, or a variable DC power supply. Start out with 6.3 volts and then measure the fil voltage and increase it gradually towards 8 volts and see how the tube improves.
Using the boosted voltage temporarily and then returning to normal can help burn off trash accumulating on the cathode sleeve and thus help emission.

[frenchy]

Also the lower you have the contrast set, the more retrace lines will show, it's practically normal on really old set to see retrace if you crank the contrast down to zip, on the sets I have anyway.
In an old 1966 repair book, it claims the 'correct' setting for contrast on all but the newest color sets (for 1966 anyway) is full OFF. I find it hard to go along with that, it results in a terrible picture!

[bgadow]

I like to have the contrast turned all the way up when possible, but different people have different tastes. I know that some color sets are basically unwatchable with the control all the way down. The whole picture just turns into a muddy mess.

[frenchy]

Originally Posted by bgadow

I like to have the contrast turned all the way up when possible, but different people have different tastes. I know that some color sets are basically unwatchable with the control all the way down. The whole picture just turns into a muddy mess.

Maybe on REALLY old color ones like my ctc-5 it works, on those the picture just plain ain't very bright to begin with compared to the mid-60's pic tubes, so usually you can't crank the brightness up high enough for the low contrast to wash it out that much, because it will start blooming anyway. Or even if it isn't blooming, it might start if something realy white comes onscreen, so you have to crank the bright down even a little more.

[bgadow]

Yeah, that makes since. My -5 has something out of kilter between the contrast, brightness & the AGC, I think. Everything has to be set just right. I'm thinking an AGC problem is at the heart of it but right now I'm just tickled it works at all. Thats it in the avatar, with both brightness & contrast cranked back.

[vintagecollect]

Maybe it's my pic tube in good emissions, but my CTC-5 has plenty of brightness. I have to try control trick & see.

Awesome avatar Bgadow!! great shot of old RCA commercial, what year of commercial??

[Jonathan]

A fix for the macrovision would be to use a DVD player or firmware that won't enable it on the video signal. Since DVD is digital, the macrovision isn't encoded in the MPEG stream. Instead, it's a flag that tells the DVD player's video DAC to generate macrovision on the luma channels. With VCRs you need a box to remove the macrovision from the video signal since it's recorded onto the tape. With DVDs, the DVD player has to be told not to tell the video DAC to generate macrovision.

With that said, I found a DVD player that seems like the last player anyone will want to buy. It's the Philips DVP-642. It plays divx and xvid too which is great. Hacked firmware is available. Hope this helps.

Jonathan

[yagosaga]

Originally Posted by vintagecollect

Maybe it's my pic tube in good emissions, but my CTC-5 has plenty of brightness.

Hi folks, all of you reported good emission tubes in their ctc-5's. Does somebody here has a ctc-5 with a low emission picture tube? Can someone provide some screenshots of a working ctc-5 with a bad 21AXP22A?

[bgadow]

Originally Posted by vintagecollect

great shot of old RCA commercial, what year of commercial??

That is from the 50th anniversary of color tv special from QVC back in '04. There is a good old thread on here about it.

[yagosaga]

Originally Posted by yagosaga

I have just got these gizmos kits. After I have assembled it, I will report here the results. I expect that it will remove the retrace lines from DVD video signals.

Last weekend I assembled the UVB kit. It is now working correct. In the first attempt it only supressed the videotext retrace lines but not the DVD data retrace lines. A check revealed that these data are placed in the vertical sync burst. Wih cutting D3 (diode) these DVD retrace lines were supressed too. This kit is working very well and offers the opportunity of full video performance of today's television sources on vintage sets. I will put a documentation on my web site in the next days. Here are some photos:

http://bs.cyty.com/menschen/e-etzold...VBTohneUVB.JPG
http://bs.cyty.com/menschen/e-etzold...DVBTmitUVB.JPG

You can read the description here (only in German):
http://www.vvt-europe.de/angebote/darius/darius.htm

[Phil Nelson]

Re "burning" electrostatic CRTs (such as 7JP4) at higher than normal filament voltage, I have been told that they are impossible to rebuild at any price. I run my 7-inch TVs at normal voltage, and enjoy them for what they can do -- for better or worse -- as long as the CRTs survive.

[yagosaga]

Hi AK'ers, Darius has written an English translation of the UVB for suppressing Teletext and Macrovision retrace lines on vintage television sets, and I have created a web page of it:
http://bs.cyty.com/menschen/e-etzold.../uvb/uvb_e.htm
Please check this web page and send me corrections of the text with private email, because our English is not so well. Please have a look on the german web page. We need a translation of the headlines of the modulator pictures.

[oldeurope]

Originally Posted by yagosaga

Hi AK'ers, Darius has written an English translation of the UVB for suppressing Teletext and Macrovision retrace lines on vintage television sets, and I have created a web page of it:
http://bs.cyty.com/menschen/e-etzold.../uvb/uvb_e.htm
Please check this web page and send me corrections of the text with private email, because our English is not so well. Please have a look on the german web page. We need a translation of the headlines of the modulator pictures.

Hi Eckhard, I think they don't have teletext stateside .

Darius

[wa2ise]

We do have "closed caption" which is similar to teletext. That is, a bit stream in the vertical interval. Also, some channels do have data transmissions (stolen credit card numbers and such) using teletext methods in the vertical interval. All these can create trash in the picture if the set doesn't suppress the vertical interval well.

[yagosaga]

Originally Posted by wa2ise

We do have "closed caption" which is similar to teletext. That is, a bit stream in the vertical interval. Also, some channels do have data transmissions (stolen credit card numbers and such) using teletext methods in the vertical interval. All these can create trash in the picture if the set doesn't suppress the vertical interval well.

I have seen these data retrace lines on screenshots of vintage tv sets here in the Audiokarma forum too, when the photos in the threads still were available. But I did not know that these data lines were used for other purposes.
Here I have some more screenshots with teletext retrace lines and with teletext retrace lines suppressed.

With teletext retrace lines:
http://bs.cyty.com/menschen/e-etzold...7_ohneUVB1.JPG
http://bs.cyty.com/menschen/e-etzold...47_ohneUVB.JPG

And with teletext retrace lines suppressed:
http://bs.cyty.com/menschen/e-etzold.../MC47_UVB3.JPG
http://bs.cyty.com/menschen/e-etzold...g/MC47_UVB.JPG
http://bs.cyty.com/menschen/e-etzold.../MC47_UVB2.JPG

The UVB board for suppressing retrace lines is easy to assemble. Ask Darius (oldeurope) for kits, he sells them for a small amount of money. I am happy that I need not to change the vintage circuits for getting no retrace lines. If you have questions please ask us.