CTC-5 almost there! - Videokarma.org TV - Video

Ralph S · #1 06-24-2009, 05:56 PM

I thought you might like to see the progress on this CTC-5U. I took the screen shots this afternoon after an initial convergence. I find the convergence on the CTC-5U to be very sensitive to any line voltage variations. It's also much tougher to get dead on the mark compared to later sets and I haven't got it licked yet. Anyway, many thanks to those who offered helpful comments on this set as it came back to life after 53 years.

Tony V · #2 06-24-2009, 07:16 PM

Fine job Ralph!

*zenithfan1* · #3 06-24-2009, 08:18 PM

Nice Job! I don't think I've ever seen a CTC 5 chassis so shiny. I see the printing and labels on it by the fuses, was it that shiny to start or did you polish around them? Great looking set.

Sandy G · #4 06-24-2009, 09:03 PM

Wish we had an "OMIGAWD !!!" smiley...

Ralph S · #5 06-24-2009, 10:34 PM

The CTC-5U was quite clean when I got it, but there was a moderate layer of evaporated bee's wax over the chassis along with a light to moderate layer of dust and grime. It was nowhere near as bad as some sets I've worked on - the worst of which had been underwater and was covered with dried-on mud. I think the wax et al was just from normal use over the years in an otherwise remarkably clean home. I cleaned the surface with Grease Grizzly followed by several damp rag rinses. When things were dry I removed the wax residual with Xylene and polished the surface. There aren't too many people who're concerned with dirt inside the TV set, but I like a clean set when I'm working on it!

I put the ID tags on the tube sockets and PC boards because I hate jumping back and forth between the chassis and the schematic when I'm working and want to find a location fast. They're Kroy labels and can be taken off pretty easily if you want to but I usually leave them on.

Also, for those of you who are eagle-eyed, you'll spot an added terminal board and a switch labeled "Operate/Test." The terminal board is where I can clip on my voltmeter to check the HV regulator current through a 1k resistor. When the switch is in "test" the 1k is in the circuit. "Operate" shorts out the resistor and puts things back to normal. The point of this is so I don't have to yank the chassis to check regulator current. The terminals are also useful to check ~B+.

jeyurkon · #6 06-24-2009, 11:03 PM

The labels are a great idea. I spend too much time looking at the location chart.

John

ChrisW6ATV · #7 06-25-2009, 12:19 AM

Fantastic pictures and chassis work, Ralph.

ohohyodafarted · #8 06-25-2009, 12:27 AM

Beautiful job Ralph. Looks great.

I wish I could find the time to get around to recapping my ctc5 Wingate and get it running. It is opperational, but for reliability sake I want to recap it. The cabinet has been professionally refinished by a furniture refinisher. I didn't want to do this one myself because there is too much curved wood trim and that stuff is a pain to strip.

Contratulations on a fine job. Your workmanship is top drawer!

BTW I like the labeling you do. How do you do that??

Bob G.

Ralph S · #9 06-25-2009, 11:17 AM

The labeling is made on a Kroy Duraype 240SE that I picked up at an auction years ago. I have no idea what the current version is or if there is one. The tape supply cartridge is: "Industrial Labeling (Black on White) P/N 2357516 L/N H286". The machine lets you have 3 different fonts in 6 different sizes - so you can have rather large type or much smaller versions that you can fit onto a circuit board.

This is probably more than you ever wanted to know about Kroy machines, but I've always found them very useful.

yagosaga · #10 06-26-2009, 12:44 PM

Congratulations to this excellent work!

Eckhard

Tomcomm · #11 06-26-2009, 02:35 PM

Great chassis clean up, its a shame that it'll be hidden in a cabinet. The color bars are virtually perfect, correct color with no bar-transition dot crawl. My CTC5 schematics show it has a 21AXP22A, has it been replaced? Does it still use the original NTSC correct phosphor or some brighter type? I'd like you to consider installing an external composite video input so you can play DVDs and really show the CTC5's potential picture quality.............Tom

Ralph S · #12 06-26-2009, 04:26 PM

Thanks for all the kind words! Tomcomm: I didn't realize that you were from Santa Ynez. What a great place that is. I've been there many times.

Re the tube: Yes, it is a 21AXP22 and I believe that it is original. I don't know if it's an "A" version. I'll let you know. There is no evidence that it has been regunned. Below the tube number is an "NBC" printed with the same material as the tube markings. I've suspected that it and this set were owned by NBC management or there was some other direct connection with NBC -but I have no proof of this. The tube checks as excellent on my Sencore CRT tester. I can send you pictures of the tube neck on Monday, when I get back to my office.

As far as putting a comp video input on this, I'm for it. The video source you saw for the color bars was a Newtek "pencil" generator via a modulator. The off the air stuff was from a digital converter box. I'd like to be able to jump the VHF tuner and IFs and get some good signal directly into the 1st video. What are your thoughts?

Tomcomm · #13 06-26-2009, 05:03 PM

Go for it! Send me a private message with your address and I'll send you a schematic of the one I use in my "55". I'll even include the chip and hope it survives through letter mail.....Tom

old_tv_nut · #14 06-26-2009, 08:43 PM

pretty darn GORGEOUS! - Congrats!

Pete Deksnis · #15 06-27-2009, 07:39 AM

Wow, you did a great job on that chassis. Clean tubes. Shiny cans. Bright chassis. Love it! Note to Steve McVoy: would you consider a 'show off your chassis' area for clean lovable chassis' like this one at the '10 ETF convention?

Don't want to rain on the parade, but is the CTC5 similar to the CTC4 in that its video amplifier has a sloped response? If so, and I do not know the answer, then a composite interface adapter suitable for the CTC2 and CTC2B would not be appropriate for the CTC5. Perhaps the CTC4 is the only odd ball in terms of nonlinear response.