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  #1  
Old 11-17-2019, 04:37 PM
vortalexfan vortalexfan is offline
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Quote:
Originally Posted by Kevin Kuehn View Post
If you haven't already it might be educational to see an actual test pattern on that set. You can download and burn a DVD from this site.

http://www.mytvtestpatterns.com/

Don't go crazy trying to center the DVD patterns on the screen, because I've noticed they vary depending on the source and how they were produced. Still they are great for checking linearity.
Thanks, downloading right now.

UPDATE: Unfortunately I couldn't get the test pattern DVD to work.

Also I completely lost my perfectly setup screen when I went to put the chassis back into its cabinet because when I readjusted the picture tube position in the chassis it made the picture tube stick out too far for the chassis to fit in the cabinet properly, so I had to readjust the picture tube's position in the chassis so it sat back further than I had it which resulted in me losing my perfect picture adjustments and now I'm having a hard time getting the picture to look right with the new picture tube position.
The adjustments are nearly impossible to do with the chassis in the cabinet but I don't want to fiddle around with taking the chassis back out of the cabinet either because its a pain in the behind to get it out and then back in again because the mount that the vertical output transformer attaches to bends and snags really easy and I've just about broke the mount off a couple of times trying to get the chassis into the cabinet.

Any ideas as to how I can go about readjusting this TV properly without having to remove the chassis out of the cabinet, or an easier way to remove and reinstall the chassis back into the cabinet without damaging it?

Last edited by vortalexfan; 11-17-2019 at 06:45 PM.
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Old 11-17-2019, 07:17 PM
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init4fun init4fun is offline
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Originally Posted by vortalexfan View Post
.....Any ideas as to how I can go about readjusting this TV properly without having to remove the chassis out of the cabinet....
Old TV repairman trick ; set up a mirror in just the right spot that you can see the TV screen from the back of the set . This works when the needed controls are all on the top or back of the chassis . If there are any under the chassis you may still need to end up pulling it , again , ah the joys of vintage TV repair ..
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Old 11-17-2019, 07:45 PM
vortalexfan vortalexfan is offline
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Originally Posted by init4fun View Post
Old TV repairman trick ; set up a mirror in just the right spot that you can see the TV screen from the back of the set . This works when the needed controls are all on the top or back of the chassis . If there are any under the chassis you may still need to end up pulling it , again , ah the joys of vintage TV repair ..
thanks, I'll give that a shot, I believe all of the adjustments I need to adjust are on the back of the TV only, none on the bottom of the set as far as I know.
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Old 11-17-2019, 11:22 PM
vortalexfan vortalexfan is offline
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OK so quick question about this TV, is the brightness and contrast controls supposed to affect the focus circuit of the TV?

I'm asking because whenever I adjust the brightness and contrast controls on the TV the screen's focus adjustments go haywire in that the screen's focus centering goes way out of whack like instead of the picture being correctly centered in the picture tube it goes way off to the right hand side of the screen and produces a large shadow on the left hand side of the screen and then the screen goes black until you turn the brightness and contrast controls almost all the way to the bottom to the point that the image is barely visable on the screen, any higher than that then I get scanslines on the screen and too high the screen goes completely black.

any ideas as to why or what would be causing this issue?

Its only been doing this since I relocated the picture tube back to its "original" position in the chassis from where I had it previously where it was providing an excellent picture and just needed its vertical size and linearity readjusted to the appropriate size for the shadow mask behind the safety glass in the cabinet.

Last edited by vortalexfan; 11-18-2019 at 12:50 AM.
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Old 11-18-2019, 01:04 AM
vortalexfan vortalexfan is offline
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OK so a little update, I dug out an old B & K Precision DynaJet 666/606 Tube Tester that a friend of mine gave me and I used that to test some of my tubes in my TV including my 1B3GT tubes.
Apparently the most crustiest nastiest looking 1B3GT tube I had in my tube stash which was a Sylvania 1B3GT tube turned out to be the best 1B3GT Tube I had in my stash and all the other ones (including the one that was in the TV when I got it that was marked "VEE" on it that I thought was actually the best tube of them all) turned out to be bad.
The B & K DynaJet 666/606 Tube tester puts a load on the tubes as if they are in circuit when testing the tubes so you get a real world test result as to whether or not the tube is actually good or not so the test results are more accurate.

The interesting thing is that the B & K Tube tester tested the crusty looking 1B3 tube as being almost NOS in the Quality Test and the Grid Emissions test showed no Deflection at all, and the other 3 tubes that my Sencore tube tester tested as "good" the B & K tester tested them as bad including the 1B3 tube that was marked "VEE" on the base (which the Sencore tester tested it as almost NOS).

So it seems I may have found my new go to tube tester...

Also when I put the Sylvania 1B3 tube into the TV the screen's brightness and contrast improved greatly and is now even brighter than it was previously and the weird focus issues that were going on with the contrast and brightness controls being rotated cleared up significantly as well.

I still need to adjust the vertical and horizontal size and linearity yet but I think Its definitely an improvement over what it was previously.

See picture below for what the picture looks like now with the good 1B3 tube in it.
Attached Images
File Type: jpg 20191118_014653.jpg (37.0 KB, 22 views)

Last edited by vortalexfan; 11-18-2019 at 01:22 AM.
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Old 11-18-2019, 10:30 AM
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Electronic M Electronic M is offline
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Quote:
Originally Posted by vortalexfan View Post
OK so a little update, I dug out an old B & K Precision DynaJet 666/606 Tube Tester that a friend of mine gave me and I used that to test some of my tubes in my TV including my 1B3GT tubes.
Apparently the most crustiest nastiest looking 1B3GT tube I had in my tube stash which was a Sylvania 1B3GT tube turned out to be the best 1B3GT Tube I had in my stash and all the other ones (including the one that was in the TV when I got it that was marked "VEE" on it that I thought was actually the best tube of them all) turned out to be bad.
The B & K DynaJet 666/606 Tube tester puts a load on the tubes as if they are in circuit when testing the tubes so you get a real world test result as to whether or not the tube is actually good or not so the test results are more accurate.

The interesting thing is that the B & K Tube tester tested the crusty looking 1B3 tube as being almost NOS in the Quality Test and the Grid Emissions test showed no Deflection at all, and the other 3 tubes that my Sencore tube tester tested as "good" the B & K tester tested them as bad including the 1B3 tube that was marked "VEE" on the base (which the Sencore tester tested it as almost NOS).

So it seems I may have found my new go to tube tester...

Also when I put the Sylvania 1B3 tube into the TV the screen's brightness and contrast improved greatly and is now even brighter than it was previously and the weird focus issues that were going on with the contrast and brightness controls being rotated cleared up significantly as well.

I still need to adjust the vertical and horizontal size and linearity yet but I think Its definitely an improvement over what it was previously.

See picture below for what the picture looks like now with the good 1B3 tube in it.
Pix looks a bit washed out and it looks like neck shadow is bugging you but otherwise not bad.

As a fellow B&K 606 owner (of roughly 17 years) I can tell you it is a good tester, and also tell you that no tester will give comprehensive real use case testing of HV rectifiers and sweep tubes....it makes a good guide to what is not worth installing but sometimes actually swapping tubes is the only way to find one the set likes.

One small nit to pick: you called the face mask for the CRT a shadow mask... that is incorrect. A shadow mask is a screen mesh found only inside the glass envelope of color CRTs. A shadow mask is placed roughly 1" behind the phosphor such that the electron gun beams must pass through its holes to hit and illuminate the phosphor....the shadow of the shadow mask prevents the beams from landing on the wrong color dots and in unphosphored screen area. You will never see a shadow mask in person unless you smash a hole in the glass of a color CRT.
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Old 11-18-2019, 11:15 AM
vortalexfan vortalexfan is offline
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Quote:
Originally Posted by Electronic M View Post
Pix looks a bit washed out and it looks like neck shadow is bugging you but otherwise not bad.

As a fellow B&K 606 owner (of roughly 17 years) I can tell you it is a good tester, and also tell you that no tester will give comprehensive real use case testing of HV rectifiers and sweep tubes....it makes a good guide to what is not worth installing but sometimes actually swapping tubes is the only way to find one the set likes.

One small nit to pick: you called the face mask for the CRT a shadow mask... that is incorrect. A shadow mask is a screen mesh found only inside the glass envelope of color CRTs. A shadow mask is placed roughly 1" behind the phosphor such that the electron gun beams must pass through its holes to hit and illuminate the phosphor....the shadow of the shadow mask prevents the beams from landing on the wrong color dots and in unphosphored screen area. You will never see a shadow mask in person unless you smash a hole in the glass of a color CRT.
Yeah, I kind of forgot about that. Anyways yes I think once I get the neck shadow and the vertical and horizontal size and linearity adjusted it should be good.
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