This past January I purchased a Col-R-Tel contraption and had it in storage until last week. I bought a 12 inch Philco (50-T1404) at this past ETF convention and restored it and shipped it here to California. I recapped the converter a few days ago and got it working yesterday. It doesn't look too bad and the wheel stays synced very well. In fact, I just finished watching it for the past hour and it did not go out once. As you can see the convergence is perfect!

Steve

Wow...Just- Oh, Wow....That thing's even more "Majic" than a REAL color set...

weird....

I'm envious. I've been looking for one.

John

And that set was full of mouse crap amongst other horrors, wonderful restoration and excellent use of the Col-R-Tel. I'm very happy this all worked out for you. Looks awesome Steve!

this is so cooooooooooooooooool

Great pictures. I'm amazed that these things work as well as they do. Good picture on the Philco. I've got a 16" with the split chassis that may someday produce a picture. :)

Although the technology is back in a modern form - DLP sets use a color wheel in much the same fashion. Guess everything old is new again sometime.

How well does this system deal with motion? Although I'd have to agree with Sandy - MAGIC.

-Jim

Steve,

Super restoration on both the Philco and the Col-R-Tel. That picture tube really provides a nice bright picture through those color filters. The sync is really locked in.

-Steve D.

Looks great Steve! Very nice job on the restoration of that rough Philco.

Darryl

your Col-R-Tel look fabulous, Steve. One just has to love anything with a spinning color wheel! Great Job.

Hi Steve,

this is a wonderful restoration project, thank you very much for sharing it with us. Can you post a photo of the color wheel?

What chroma signal do you use for input? NTSC or CBS field sequential?

More photos and reports are wellcome!

Kind regards,
Eckhard

interesting topic, but I do not understand how to operate the color wheel in sync with the signal "all electronic" as far as I remember broadcaster must have the same standard. clarifications are welcome

Motion has very little to do with it as the picture is "already there". The disc spins fast enough to accomodate the color shift. If done right, you almost cannot tell that you are not watching a "real" color TV as this technology works quite well. The later ones are so good that you cannot tell as the one demonstrated at the ETF meet a few years ago with a 14" monitor was so good (and quiet) that I could not actually tell the difference if I didn't know any different.

I wish I could find the electronics for my Color R Tel. Anyone know of one??

Thank you all for the kind replies regarding the resoration!

I'll try to answer a few of the questions.

Eckhard, I did not take a photo of the wheel but it is just 6 segments of filter material glued together. It is not a rigid wheel but rather quite "floppy" as you could not stand it on end.

The converter converts NTSC to field sequential. The sync pulse is taken off the vertical and the converter knows what color is in front of the CRT from a mechanical commutator at the hub of the wheel. BTW, that arrangement causes a lot of noise in the picture.

Julian, don't confuse this with the CBS sets at ETF. This wheel runs at 600 rpm whereas CBS is over 1400 rpm. There is considerable flicker in the Col-R-Tel picture and fast movement causes the color to break up. That can even happen when the viewer blinks!

Steve

GREAT restoration!!!! I've never seen a wheel on NTSC in operation. Some time, I'd like to invite myself to come see it :)

Charles

Beautiful and how humbling when we see how far we've come in colour tv.

Reminds me when I fist saw my neighbour's 26 inch Zenith colour console in 1966.

The 1st colour program I saw was 'Let's Make a Deal'

The 1st colour program I saw was 'Let's Make a Deal'

I love that show! I watch it a lot on my '60s Zenith sets.

Hey Steve,

WCBS is still broadcasting NTSC on channel 2 here. How bout shipping that contraption to Asbury Park and I'll watch it for you, input with true OTA NTSC!

Obviously I'm jealous.

Great job. Enjoy it.

Pete

Fantastic restoration job mate! Seeing more examples of these colour converter wheels working and in action always amazes me, it's so cool this technology existed back in the day!!! It's like you can practically turn every B&W TV set into a colour set with one colour wheel. Couple of questions, I understand these wheels were probably commonly used with say 10 to 15 inch B&W sets made in the late 40s and early 50s, just wondering if there's been demonstrations of these wheels on that really large screen B&W TV that was put in production around 1951 (forgot the brand name but collectors would know what I'm talking about)? Also can these wheels easily be used on a pre-war B&W US TV set? Anyways if you could, put up a YouTube demo of your wheel in action, would be so cool to see this awesome technology in action!

Hi Steve,

The converter converts NTSC to field sequential. The sync pulse is taken off the vertical and the converter knows what color is in front of the CRT from a mechanical commutator at the hub of the wheel. BTW, that arrangement causes a lot of noise in the picture.

What is the converter? Is it part of the Col-R-Tel, or do you use an Aurora converter?

Best regards,
Eckhard

Thank you all for the kind replies regarding the resoration!
There is considerable flicker in the Col-R-Tel picture and fast movement causes the color to break up. That can even happen when the viewer blinks!

Steve

Fantastic to see this--kudos for an amazing job--and interesting to hear about the color break-up when blinking. The same problem occurs with DLP projectors, which is why I can't stand them, especially if black-and-white material is being projected.

Now I'd like to see a replication of the DuMont demonstration of a 24" set with a color wheel, that supposedly knocked out the power at an FCC hearing. Or that's the way I heard it...did that actually happen?

Pete: Send me your good CT-100 and we'll talk!

Eckhard: By converter I am refering to the chassis that sits on top of the TV cabinet behind the disc.

I think there was a discussion some time ago about a color wheel for the 30 inch Dumont. I don't remember if it was ever reallt attemted or not.

Aussie: I believe that a wheel could be used on a prewar set. Actually there was experimentation of mechanical color before the war. If the Col-R-Tel would work on a prewar I do not know. I have no idea how to put something on YouTube- sorry.

Steve

Also can these wheels easily be used on a pre-war B&W US TV set?

There is certainly nothing unique about a pre-war set that would preclude the use of a color wheel. Somewhere I have documentation of a pre-war RCA TRK9 with an internal color wheel.

Darryl

Attached are two pix from my Col-R-Tel from about 2 years ago attached to a Philco also. Brave attempts were made to use a RCA, but it narrowed the bandwidth in the video amp section which would not pass NTSC information. Philco does much better at that.

Looking at the pix, you can see the obvious degredation of the pix with this Rube Goldberg contraption, but it does work. Forget resolution in the final viewing. You can see the shift of the color in mine because there is no delay line to line up the color processing with the luminance like a color set of the day would use. So it goes for fake color. And then there is the debate of adding delay in the set which would make it not factory original. I opted for original as viewed in 1956, errors and all. And the blue information is more to the turquoise side due to the filters used.

Changing the CRT to an aluminized version helps with the brightness to get through those filters. I did this as it was a 1956 possibility

Steve K...you note about the commutators inducing noise is spot on. I found that if I pulled the wheel and buffed up the circuit traces the bent wire brushes ride on, things cleaned up right away.

The aluminum band around the shell is one of the most important parts of the assembly. It keeps the spinning disc from interacting with atmosphere outside the shell. The Bernoulli effect kicks in here. The wheel is a soft plastic and will compress against the inside of the wheel shell if unprotected and drag it down. Think old Bernoulli drives where the disc was forced down to a head as it spins.

And there is a small secondary chassis to attach to the yoke of larger CRT (more than 12") size sets to shrink the pix to a useable size for the shell opening.

A broken brush has mine sitting on the sidelines until I send the assembly to a genius for rebuilding when I find the time. Pete Y, I have not forgotten you.

Dave A

Pete: Send me your good CT-100 and we'll talk!

Eckhard: By converter I am refering to the chassis that sits on top of the TV cabinet behind the disc.

I think there was a discussion some time ago about a color wheel for the 30 inch Dumont. I don't remember if it was ever reallt attemted or not.

Aussie: I believe that a wheel could be used on a prewar set. Actually there was experimentation of mechanical color before the war. If the Col-R-Tel would work on a prewar I do not know. I have no idea how to put something on YouTube- sorry.

Steve

Ahh yes, that's right, CBS were experimenting with the colour wheel with their field sequential system as early as 1940, forgot about those experiments.

I hope there will be an experimentation on setting up a large colour wheel for the 30 inch 1951 Dumont Royal Sovereign TV set http://www.earlytelevision.org/dumont_ra119.html as it would be real cool to see colour pictures out of that great TV set.

Dave:

I did bend the contact wires and cleaned the traces which did help. I should have also cleaned the ends of the contacts but didn't. I hate to think about pulling that all apart again!

According to the 1956 Technician Circuit Digest there was a delay line option for the Col-R-Tel. I chose not to add it as well.

I've heard that RCAs do not work well with this color wheel. I did find that I get better color on the Philco by taking the video signal directly off the plate of the video output rather than at the CRT.

Steve

I have to wonder if one could build a modern "clone" of this thing using off-the-shelf ICs etc. I know I know it goes against the "all tube" mantra, but say you wanted to "colorize" one of those little 5" B/W chinese sets as a quirky project?

Check out this link:
http://www.earlytelevision.org/2009_convention_photos-benham.html

This was Cliff Benham's ETF presentation this past May. He is actually using CBS color but with modern components with excellent results. I believe he has made a modern NTSC version as well.

Nevermind, I didn't read the last post before I posted. It was about Cliff Benham's presentation. It was the best Col-R-tel EVER.

... just wondering if there's been demonstrations of these wheels on that really large screen B&W TV that was put in production around 1951 (forgot the brand name but collectors would know what I'm talking about)?

You mean on the 30-inch DuMont Royal Sovereign? Here's Allen showing it off now:

DuMont's demonstration of the color wheel needed to convert a 30" B&W set to receive CBS field sequential color was strictly a shot at CBS and how impractical the GIANT size wheel would have to be. This was, of course, not a working color wheel.

-Steve D.

Beautiful, Steve.

the Dumont demonstration was a stunt ...and CBS did have the drum set which was 17" set and looks pretty cool ...

http://www.earlytelevision.org/images/CBS_ColorDrumReceiver.jpg and which would be fun to recreate!

but the col-r-tel adaptor is amazing .... must have been even more astounding in the 1950s

Great set!!

:thmbsp:

Hey Steve,

Here's a couple of pictures of my Color-Tel. It's permanently attached to an Admiral console.

Chuck

[QUOTE=ceebee23;2850736]the Dumont demonstration was a stunt..."

Well possibly, but Dumont setup a real demonstration of CBS Color in a Philadelphia courtroom with a DuMont Royal Soverign 30 inch set and a 6 foot color wheel. They were there to protest against CBS color in favor of RCA's color system. It's an interesting story. It is written up in either 'Radio and TV news' or 'Radio electronics' in the editorial section in either 1950 or 51. I'll try to find it and post it.
Meanwhile...

Steve, your Col-R-Tel Philco looks really great! Mine is on the same set but I can't get pictures with good grayscale like your's for some reason. What's your secret?
Don't know where I've been but I missed this whole thread and want to comment on some of the posts. Attached is an early picture of my Col-R-Tel while I was restoring it after 46 years.

OOPS! Forgot to hit the upload button...

OOPS! Forgot to hit the upload button...

Don't know what I'm doing wrong???

Now I do. I had posted this image several years ago in another thread.
This is a different version of the Philco-Col-R-Tel during restoration in 2005.

I had a great visit with Steve K yesterday... My first experience seeing a live, working Col-R-Tel! It blew me away with the performance. I had imagined a flickering, dim, blurry image, but I have to say it's better color than a tube, and the flicker is not nearly as bad as I thought. And doggone STABLE too! I'm shocked that you don't have to sit there with your hands on the controls. I further suggest that this particular restoration's performance is attributed to the one who did the restoration! Thanks Steve, for the demonstration! A couple years ago on a road trip Back East, I've also seen a CBS (Oops, I forgot: I'm sworn to secrecy).

Charles

I have to wonder if one could build a modern "clone" of this thing using off-the-shelf ICs etc. I know I know it goes against the "all tube" mantra, but say you wanted to "colorize" one of those little 5" B/W chinese sets as a quirky project?

An ETF member brought his color wheel set built about as you describe to the 2008 convention and it was great. Made beautiful color.

It's possible to build one using I.C.s and circuitry that's appeared in electronics magazines over the last 20 years.

Where has that guy been? "Modern day" color wheels are alive and well and going strong. Just go to the ETF museum when they have their yearly get together and see many examples. They also look great and I saw one that you can NOT tell that it wasn't a color CRT!!

Pioneer uses the same technology with their DLP big screen systems usilng an LCD instead of a color wheel and it also lokks fantastic!