Add RCA Component Sound And Video Hook Ups
 

Just curious if anyone has had any luck trying to add a component video and sound hook up to a tube TV set like ctc 15,28,38 or other. I know this was afford for ctc 38 sets for special models think there called Lyceum which I have not been able to find a schematic for probably cause of there rarity. I am thinking about trying to do this but want to see if anyone else has or may have a schematic for a tube set that had this option.

While not a color set, the 23" Setchell Carson and Wollensak school tvs had video inputs. i have a Wollensak 2200 with inputs. i dont have a schematic for it though.

Not for component, only composite. Component would require extensive circuit changes, as you would be taking the demodulation section out of the equation.

You'd have to find the amplitude and polarity of the detected video signal in the set, and build a video amp to make the 1Vp-p baseband input video signal look like the one at the detector. Some color TV sets used one detector for the luma signal, and another to detect the chroma signal, both off the IF amps. That becomes harder to convert.

I had success with my Zenith 29jc20 set I got some help from my friend Danny and we made it work. It makes a better picture and seems to have eliminated interference I used to get which is bad at my present location and the tuner can be on any channel since it has been bypassed. No more need for a converter box to and if they ever bring back the VHF tuner I can put it back the way it was. Some how I doubt that will happen. The bar on the screen of the TV is from my camera in the picture I added. I may try this on a RCA next.

I did this with a BPC set, placing the CECB inside the cabinet, to act as the tuner/IF strip. And also the CECB becomes the now digital set's remote.
http://videokarma.org/attachment.php...3&d=1315097178

I doubt the VHF channels will ever come back. Most of the UHF TV channels (channels 14 to 52) have been auctioned off to other services, so they will never again be used for television broadcasting in this country. The remaining 38 channels may well be auctioned in the future.

The VHF channels are no longer used for telecasting, and may well be auctioned to other services before long as well. The few FM low-power stations that operate on channel 6, for example (there is one such station in Cleveland and one in Chicago; there may be others as well) will have to cease their operations some time this year, as I think the FCC is planning to reassign the entire VHF television spectrum by the end of the year. The goal seems to be to clear the entire VHF and UHF TV spectrum of all television stations, so that the frequencies can be used for other things such as land mobile, cellular telephones and the like.


I don't know how you were able to modify your Zenith chassis 29JC20 to receive digital TV signals, unless you are using a digital-to-analog converter box feeding the set's original VHF tuner, set to channel 3 or 4.

I do not know how you managed to bypass the VHF tuner if you are using a converter, as these boxes output to either of the two VHF channels I just mentioned--the VHF tuner would have to be operational and set to one of those channels before the converter would work. I seriously doubt that these converter boxes have provisions for direct input to the IF strip, or to the UHF tuner input of the VHF tuner. The latter is the only way I can think of that the box would operate without the VHF tuner; however, even then the VHF tuner would have to remain on the "UHF" position to receive the output of the converter.

Best part of this kind of "modification" is that it is entirely non-invasive and reversible. No holes drilled, no switches mounted etc.

Good job and of course, you were rewarded wit a great picture. Thanks for sharing the information.

Pretty much all converter boxes have composite video and analog audio out. Also an easy way to connect a DVD player

Sounds like OP had mixed up terms, I though he was asking if a set can accept component inputs- not composite.

I'm Bad!! I meant composite I got that mixed up.:scratch2:

Has anybody here figured out a way to modify an older set to take component video? I imagine that it would be much more difficult to accomplish, but even better picture quality might be obtained. :scratch2:

How about an isolated input circuit for use on "hot chassis" sets?

jr

IIRC user Tomcomm did that on his 21CT55 along with composite video, and S-video.....I would not be surprised if he tried do VGA as well.

I think you'll see the biggest jump in image quality if you can modify the set to accept "S video". That's separate luma and chroma, not mixed together. This would be non-trivial to do, though, you need to find the chroma luma separator (usually some sort of LC trap or bandpass circuit). Then you have to inject (with the right amplitude and polarity) the luma into the circuit that received the luma from the separator, and chroma the chroma.

As for hot chassis sets, an isolation transformer would be best, but be careful where you install it, to keep stray magnetic fields out of the CRT.

Adding a S-video input probably wouldn't be worth it because I don't think DVD players are commonly equipped with S-video.

I'd certainly like to know how to do composite though. That ball has been tossed around here before with no definite answer as far as I know. I saw a video of an XL-100 that someone had modified with a switched composite input, but the current owner hadn't done it.