View Full Version : Opinions on RCA's CTC-38 chassis
drh4683 01-09-2008, 12:15 PM Im curious as to how good the picture quality is on other collectors CTC-38 sets?
The picture is OK, but "soft" like a motorola. RCA tvs always seemed to have a nice sharp picture.
I have two CTC-38's and both have strong crt's but wish the quality of the picture could be better. I also do not like that the CTC-38 does not use a HV control. I had a table model CTC-38 that I sold to chad a few years ago and that had the same soft picture.
Is this a characteristic of this chassis? I have a couple CTC-31's, but the picture is excellent on those. Anyone remember CTC-38's when they were new, or still in every day use?
sampson159 01-09-2008, 08:13 PM i have one that has a soft picture also. tube checks excellent,so i expect it to be as good as some other rcas. high voltage is on the money ,but it just looks soft. i had the same issue on an old accucolor. great tube,soft picture. the very next rca(xl-100) had a great picture with essentialy the same tube,sans the safety glass. been there.
jstout66 01-09-2008, 08:43 PM Doug, The CTC-38 is a set I DO remember well.
When I worked in my Uncle's shop in 1979, these would have been 10-11 years old. There were a TON of them on the service route. They were a money-maker for the TV repair people back in the day. They were the sets that would be guarenteed to eat a flyback EVERY summer. They also were known for IF problems. I can honestly say I never remember one having an outstanding picture. Not a horrid picture, but never outstanding. I even had one that I liked because of the cabinet style, but was not happy with the picture. I had my Uncle install a NEW Chromacolor replacement tube and it still didn't look good. The chassis just wasn't built to put out a good picture. The CTC-38 and more deluxe 39 were RCA's LAST tubed console and RCA really cut corners. Look in 1968/1969 magazines and you will see that they were bargain priced and a value leader for RCA. Those chassis were pushed to the limit on high-voltage to produce the picture they had and that was why they went thru so many flybacks. My Uncle would only use Thordarson as replacements, because the RCA ones would NOT hold up.
I'm sure anyone that was working in a repair shop in the mid to late 70's will back me up on this.
radiotvnut 01-09-2008, 08:59 PM I was showing my CTC38 that I'm looking for a fly for to an old repairman friend and he said he changed MANY flybacks in these. Anyway, my Aunt had either a 38 or 39 console. I was about ten when it finally died and said "no more" in '86 or '87; but, it seems like the picture was a little on the soft side. Her set was the newer version with the block RCA logo and tilt out control bin. The colors seemed OK; it just was not quite as sharp as the XL-100 that came out in the early '70's. In fact, I've seen a solid state XL-100 in the exact same style cabinet as her tube set. If I find a flyback for mine, we'll see how it looks!
Chad Hauris 01-09-2008, 09:41 PM It's been a little while since I have used the CTC-38's, need to get them back into service. I have two 22" table models plus a console and, at my parents' house I have a CTC-39.
It seems like the performance of the 38 and 31 are pretty similar. Some of my examples I think have somewhat weak CRT's so I may not be getting the best from them.
The CTC-39 really seems to work the best of all of them but it is a school model which had very little use plus a black-matrix CRT.
As far as I know the HV/horizontal output circuits are almost the same on the CTC 31, 38 and 39...the 38 and 39 have transistorized IF and a different chroma circuit.
The later CTC-38/39 seemed to use zener diodes or something in the 6BK4 circuit although I seem to remember one of the 38's having an adjustable HV control.
sampson159 01-10-2008, 08:06 AM i used a sylvania crt in a 38 once and it still had a soft picture. you are right,it was a very low quality set. i have used sylvania 25vamp22 in rca xl100 a and colortraks and they really look good and hold up well.i think it is a perfect swap. in that 38,it just looked bad.soft focus,no sharpness,color was okay.disappointment. i think all of them had flybacks replaced. i replaced 2-3 i remember. just a really bad set from a good manufacterer.
kx250rider 01-10-2008, 11:32 AM I don't have a schematic in front of me, but I thought that the 38s did have a pot for HV adjust. Maybe some early or late production?
I worked on a zillion of them, and I agree that their weak spot was the IF circuit. Also a lot of FBTs. Most of the problems were bad solder connections, though. Not a great performer. I had one in the late 70s when I first started as a TV hobbyist, and it was our daily watcher for a year or 2. Like popular opinion on this thread, it was a bit soft. I also had a Packard-Bell roundie that had a deeper, more crisp picture.
The CTC-39 added a peaking control to the front panel, which helped a bit.
Charles
drh4683 01-10-2008, 09:13 PM thanks for the replys. I just wanted to make sure that I wasnt missing something about this chassis. Ive never seen one with a great sharp picture. Ive gone over circuits and everything seems to be as good as possible.
As for the HV control, late production CTC-31's didnt have it, nor did various versions of the CTC-38. I have an early production 38 and I think it does have a HV control, but the CTC-38X versions didnt have it. Its a pain, as those 1% tolerance resistors drift over the years and the HV goes up or down a few KV and there is nothing you can do about it but go over the entire circuit and test everything, or leave it alone if its close enough, as long as its not over 25KV.
nasadowsk 01-10-2008, 09:58 PM I think my grandma had one - it was a late model tube set, 25inch or so, with the flip out speaker with the controls for the color, etc.
Picture was always wavy, cooked 6ME6 constantly, roasted a flyback or two...
El Predicta 01-11-2008, 08:57 AM The 38 chassis was tough to align. I remember that RCA had dozens of pages of updates/mods. after it came out. The 39X incorporates all the changes.
Many, myself included, think other chassis' like the CTC 25X and even the 16X, had much better video and color. Bottom line is that despite RCA's huge industry status-they did not turn out consistently good products every year.
kx250rider 01-11-2008, 11:15 AM Taking this to another level, I don't think any RCA had a really good picture in the last 40 years, EXCEPT maybe the CTC-120. It had I&Q demodulation, and seemed to have really good definition. I mean the 25" direct view version; not the one that they stuck in a 45" projection set. The 25" version had some models with a smoked glass front cover, which really made nice contrast and deeper color.
Charles
vintagecollect 01-11-2008, 12:07 PM ...
Carmine 01-11-2008, 06:22 PM Those CTC-38s seemed to be the most common curbside find when I was a kid in the 80s. They were always cooked... PCB boards burnt, other major problems.
Second most common curb find was probably a Zenith 20xxxx set from the same era. Those either worked, or just needed cleaning or a few new tubes.
After a while, I just started doing horrible kid-like things to the RCAs after I stripped the tubes, and fixing/selling the Zeniths. As I recall, one RCA even ended up at my elementary school with a cinderblock inside of it. :sigh:
mhardy6647 01-11-2008, 07:16 PM I grew up with a CTC-38 :-)
radiotvnut 01-11-2008, 08:06 PM I do think a lot of older people liked the softer picture because it was easier on the eyes. I'll agree that the Zenith's were easier to fix and they also had the best picture. A lot of those were still going well into the '80's and early '90's.
Robert Grant 02-07-2008, 07:20 PM Yes, I certainly remember the CTC-38. I still have the Photofact for it (a nice even set 1000).
As a very small child, if my mon lost track of me in a department store, she knew right where to find me - where the color TVs were!
On 6 December, 1969, my parents gave us all money to see a movie at the nearby Vogue theatre. The real treat was when we got back - the old B&W Zenith was replaced by a CTC-38! (GL759WK, I think) it also had something I had never known about called UHF (and WKBD-50 changed afterschool hours for us kids drastically).
Yes, I can never remember the picture of the CTC-38 being sharp, and, it was idled for service quite often from about the third year on. After the power transformer was replaced, the 25XP22 gave out another year later (good thing Dad bought that service contract!).
It seemed from then on, things got even worse. I learned how to fix TVs, and it became up to me to keep that lemon running. It seemed that every connection on all of the PC boards failed to the point where I just had to give up.
We watched the first Space Shuttle landing on a 24" Emerson B&W that was ten years older than the RCA!
I've been thing about looking for a CTC-16 or earlier, but, are these as bad off as the CTC-38 was?
Rob
Chad Hauris 02-07-2008, 08:18 PM I have seen cases of burned wiring due to heat in CTC-16 and CTC-15's but the problems don't seem as bad on the circuit boards as the CTC-38's. Maybe because the 15's/16's had a larger chassis layout and 3 or 4 circuit boards as opposed to the 2 on the CTC-38, so the heat was not so concentrated. The CTC-15/16 are also an all tube chassis as opposed to the transistorized IF stages on the CTC-38.
There are some rectangular sets such as CTC-17, 30 etc. which use the "deluxe" chassis like on the CTC-16. These just add in the pincushion components for the rectangular tubes. The CTC-31, 38, & 39, were a smaller, cheaper chassis.
rcaman 02-07-2008, 10:22 PM Taking this to another level, I don't think any RCA had a really good picture in the last 40 years, EXCEPT maybe the CTC-120. It had I&Q demodulation, and seemed to have really good definition. I mean the 25" direct view version; not the one that they stuck in a 45" projection set. The 25" version had some models with a smoked glass front cover, which really made nice contrast and deeper color.
Charles
you are thinking of the ctc132 chassis i didnt care for then either.
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