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-   -   Rca 21tc205 (http://www.videokarma.org/showthread.php?t=269936)

Gregb 01-01-2018 06:04 PM

Rca 21tc205
 
I am working on my RCA 21TC205 and have it all recapped and pretty much all new resistors and it is working pretty good but there is one issue I was hoping you guys might help me with. When ever some text appears on the screen it has what I will call a shadow following it. This also occurs when a square object appears, trails or shadows follow the corners. I did an alignment per the RCA manual I have for it and some adjustment was needed and it does get very good reception other than this issue.
Any thoughts?

Gregb

Electronic M 01-02-2018 12:08 PM

That is probably smearing or ringing.
Did it do it before the alignment?
If so have you tested your RF signal source with another CRT TV that is known to work and confirmed there is no smearing in the signal source?
If not can you put the adjustments back?

Have you tried the fine tuning adjustment?

On vintage TVs it is best NOT to align the video IF (and to an extent the tuner) unless they are not allowing a reasonably good picture. It takes a good deal of skill, experience and calibrated signal generation equipment to make an improvement on the original alignment.

Does your set have a DC restoration circuit or DC coupled video circuits between the detector and CRT? Sets that lack DC video coupling and restoration sometimes have a certain degree of smearing on sharp monochrome transitions by design...We get used to modern color TVs that have all have DC restoration and forget what it looks like on monochrome sets where it was not considered a standard design requirement.

Gregb 01-02-2018 07:28 PM

I have a number of other sets that don't do this so I think my source is OK. It did not get very good reception before the alignment and there was almost no sound. The sound and picture are now very good other than this issue. Its not annoying by any means so I am not overly concerned but thought if there was something easy to try I would give it a go.

Gregb

Penthode 01-02-2018 08:29 PM

Can you provide some screen shots?

Gregb 01-03-2018 06:41 PM

I will try to get a shot of it tonight.

Gregb

Penthode 01-09-2018 08:51 PM

Quote:

Originally Posted by Gregb (Post 3194224)
I will try to get a shot of it tonight.

Gregb

Still curious and waiting for a picture or two :banana:

Gregb 01-09-2018 10:34 PM

I have tried and can't seem to catch the issue with my camera. I think I will just leave it as is and not worry about it. The couple friends that have seen it say it looks great so maybe I am being to picky.

Gregb


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