Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Early Color Television

We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #61  
Old 05-18-2011, 03:45 PM
miniman82's Avatar
miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,073
Here is my CTC-7 with grey faced 21CYP22, with Philco 21FBP22 green faced tube sitting on top. The monitor to the right is a Sony security monitor, with NTSC comb filter decoder.

http://www.videokarma.org/showthread.php?p=2998927


Grey faced 21AXP22 has similar color to the CYP tube, where anything with a green sulfide set of phosphors looks more orange-red than true red to my eye. We'll see what the green faced 21AXP22 in the CT-55 ends up looking like, I assume it will have similar response to a 15G.
__________________
Evolution...
Reply With Quote
  #62  
Old 05-18-2011, 04:37 PM
ohohyodafarted's Avatar
ohohyodafarted ohohyodafarted is offline
Bob Galanter
 
Join Date: Sep 2005
Location: Whitefish Bay, Wi (Milwaukee)
Posts: 939
Nick,

I guarantee you it will be nothing short of DAZZLING! I hope some day you can get up here with Mark (he needs to make a trip to get his 21" roundie safety glass) so you can see first hand what a wonderful picture a CT55 will produce. But Murphy's law says if you come by it will blow a fuse.

Bob
__________________
Vacuum tubes are used in Wisconsin to help heat your house.

New Web Site under developement
ME http://AntiqueTvGuy.com
Reply With Quote
  #63  
Old 05-18-2011, 07:29 PM
old_tv_nut's Avatar
old_tv_nut old_tv_nut is offline
See yourself on Color TV!
 
Join Date: Jul 2004
Location: Rancho Sahuarita
Posts: 4,276
[QUOTE=Tomcomm;3003530]...I read somewhere the modern SMPTE phosphors are more orange/red since they produce better "flesh tones" with less accurate chroma demodulators...QUOTE]

I was on the SMPTE monitor committee, and I can tell you that the colors were standardized based on what was available in the tubes made with controlled phosphor batches and supplied in Conrac monitors. In "SMPTE C primaries," the "C" stands for Conrac. The relatively slight variations in red phosphors over the years has little effect on flesh tones compared to the changes in green and blue, especially green.
Reply With Quote
  #64  
Old 05-18-2011, 07:35 PM
cbenham's Avatar
cbenham cbenham is offline
VideoKarma Member
 
Join Date: May 2006
Posts: 468
Quote:
Originally Posted by old_tv_nut View Post
In "SMPTE C primaries," the "C" stands for Conrac.
I didn't know that.
Sitting on that committee must have been a very interesting time. #;^)
Cliff
Reply With Quote
  #65  
Old 05-18-2011, 07:46 PM
old_tv_nut's Avatar
old_tv_nut old_tv_nut is offline
See yourself on Color TV!
 
Join Date: Jul 2004
Location: Rancho Sahuarita
Posts: 4,276
Quote:
Originally Posted by miniman82 View Post
Here is my CTC-7 with grey faced 21CYP22, with Philco 21FBP22 green faced tube sitting on top. The monitor to the right is a Sony security monitor, with NTSC comb filter decoder.

http://www.videokarma.org/showthread.php?p=2998927


Grey faced 21AXP22 has similar color to the CYP tube, where anything with a green sulfide set of phosphors looks more orange-red than true red to my eye. We'll see what the green faced 21AXP22 in the CT-55 ends up looking like, I assume it will have similar response to a 15G.
When you have a variety of tubes running, we can measure them with the Spyder 3. It may not be as accurate as the spectroradiometer, but it should indicate the direction of the differences.
Reply With Quote
Audiokarma
  #66  
Old 05-18-2011, 09:54 PM
miniman82's Avatar
miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,073
That's the plan, anyway.

What I want to do is have the green AXP, grey AXP, CYP, and green FBP all measured. I have date codes for all of them, so it will be interesting to see the progression of phosphors through the years. Ultimately I would like to have a database of them all built up, so we can see what response they have in order to shed some light on the exact colors a person will see when they use a certain tube in their set.

That way, we can replace subjective things (what people's eyes are seeing) with something objective and concrete (at least within the limits of the instrument). Only then will we be able to say 'tube x does in fact have an orange-reddish phosphor, where tube y has a more correct color.'
__________________
Evolution...
Reply With Quote
  #67  
Old 05-22-2011, 07:28 PM
Pete Deksnis's Avatar
Pete Deksnis Pete Deksnis is offline
15GP22 demo @ ETF 2007
 
Join Date: Jan 2005
Location: Big Rapids, MI
Posts: 734
Quote:
Originally Posted by miniman82 View Post
Double post?
Sorry about that. Was on the road after ETF and just now saw the X2 flub,

Pete
Reply With Quote
  #68  
Old 05-23-2011, 02:02 PM
Username1's Avatar
Username1 Username1 is offline
Not sure how I got here.
 
Join Date: Dec 2009
Location: Orange County NY
Posts: 3,466
I think testing all those tubes would be a good idea. But you should test in a way that normalizes all the tubes. For example, use a simple light meter to set all the tubes to the same or very near the same overall brightness level. Use the same method to make a white screen on all the sets. You would have to use the same equipment on the test of each tube. I think it would also be neato to include some of the 23" and 25" tubes from the 60's through the end of crt production in the tests as well.
__________________
Yes you can call me "Squirrel boy"
Reply With Quote
  #69  
Old 05-23-2011, 04:04 PM
miniman82's Avatar
miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,073
Quote:
Originally Posted by Username1 View Post
you should test in a way that normalizes all the tubes. For example, use a simple light meter to set all the tubes to the same or very near the same overall brightness level. Use the same method to make a white screen on all the sets.


All the tubes would have proper greyscale tracking before the test, along with purity and the whole bit. Every effort will be made to ensure a valid test occurs.
__________________
Evolution...
Reply With Quote
  #70  
Old 05-23-2011, 05:31 PM
old_tv_nut's Avatar
old_tv_nut old_tv_nut is offline
See yourself on Color TV!
 
Join Date: Jul 2004
Location: Rancho Sahuarita
Posts: 4,276
Just got outbid on a used I1 spectroradiometer on ebay - would have been a good price if it sold where I stopped. Maybe some other time...
Reply With Quote
Audiokarma
  #71  
Old 05-24-2011, 12:40 AM
miniman82's Avatar
miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,073
That sucks. Oh well, this is already going to happen it's just a matter of when!
__________________
Evolution...
Reply With Quote
  #72  
Old 05-24-2011, 12:48 AM
miniman82's Avatar
miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,073
Back to the subject at hand...


I recently discovered that I hate metal polishing.

But I can't argue with the results. The trim around the CRT window is badly tarnished, so I set about fixing it. First I tried a buffing wheel and compound, but that didn't even faze it. The stuff is just too old, and covers 100% of the trim. Plan B- I wet down some paper towels with vinegar, and draped them over the trim overnight. It looked like hammered dog crap when I woke up, but some polishing stuff buffed the light surface corrosion right off. After that, I hit it with some Never Dull and holy cripes does it look good now! I mean, it's literally a MIRROR SHINE. It's gonna take many more hours of work to get the rest of the trim pieces done, but results like this are well worth it in my book.

Think it's a good idea to hit it with clear laquer after I'm done? I don't want to do this every year...

Apologies for the pics, they don't do the brass justice. A shine like this is hard to capture with a camera.
Attached Images
File Type: jpg IMGP4460.JPG (74.9 KB, 42 views)
File Type: jpg IMGP4462.jpg (59.9 KB, 39 views)
__________________
Evolution...
Reply With Quote
  #73  
Old 05-24-2011, 02:41 AM
Phil Nelson's Avatar
Phil Nelson Phil Nelson is offline
VideoKarma Member
 
Join Date: Jan 2006
Posts: 3,875
Clear lacquer can keep brass nice for a long time. It may be a little trickier to spray lacquer on shiny metal than on wood. Little uh-ohs jump out at you.

This may sound nutty, but wax can also be used. When I had a guy restore some antique light sconces, he added a couple of little new switches. He dipped those in gun bluing to make an aged color and then used Howard's Feed 'n Wax over all of the brass, old and new. I was skeptical, but this was about 10 years ago, and they look exactly the same.

Phil Nelson
Reply With Quote
  #74  
Old 05-24-2011, 09:38 AM
zenithfan1's Avatar
zenithfan1 zenithfan1 is offline
Mark
 
Join Date: Jan 2008
Location: Kenosha, Wisconsin
Posts: 4,140
Lookin' good Nick! That trim looks new!!
__________________
My TV page and YouTube channel
Kyocera R-661, Yamaha RX-V2200
National Panasonic SA-5800
Sansui 1000a, 1000, SAX-200, 5050, 9090DB, 881, SR-636, SC-3000, AT-20
Pioneer SX-1500TD, ER-420, SM-B201
Akai 4000DS Mk-II
Motorola SK77W-2Z tube console
Reply With Quote
  #75  
Old 05-24-2011, 03:58 PM
ohohyodafarted's Avatar
ohohyodafarted ohohyodafarted is offline
Bob Galanter
 
Join Date: Sep 2005
Location: Whitefish Bay, Wi (Milwaukee)
Posts: 939
Nick,

Although this method does not produce a Bright High Mirror shine, this is what I do.

To get a nice brushed satin finish, I remove the tarnish and corrosion using 3M Scotch bright wheels on a polishing arbor. It leaves the finish looking like it has been buffed with steel wool, sort of a satin finish. This process takes about 1 hour on the polishinhg arbor for the exact same trim as on your 21CT55. I did the trim for the Hallicrafters CTC4 clone in just this manor yesterday.

If you however want a higher luster, the next step is to hit it with 0000 steel wool. Then I always spray with clear nitroceluolose lacquer. I have also used clear ACE brand enamel from Ace hardware with good results. The Ace brand leaves a heavier coat, but it is a bit trickier to work with on a high luster finish.

The trim I polished up yesterday had been subjected to moisture over a long period of time. As a result there are microscopic pits in the surface that are the color of copper. (brass is mostly copper, usually 90% or more) The tiny pits show up more if the surface is polished to a bright luster mirror finish so, I dedided to use a brushed satin finish because it looked better and the pits are less noticable.

I am not sure what the correct finish is. Is it a bright mirror finish or a brushed satin finish? In any event I have used the brushed satin finish on a couple other sets and it looks quite nice.

Bob
__________________
Vacuum tubes are used in Wisconsin to help heat your house.

New Web Site under developement
ME http://AntiqueTvGuy.com
Reply With Quote
Audiokarma
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 02:25 PM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
ęCopyright 2012 VideoKarma.org, All rights reserved.