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Discussion Starter · #1 ·
I recently bought the Panasonic CT36HX42 as a replacement for an RCA 36" HDTV that I had bought a couple of years ago and had numerous trouble with. I have had a couple of annoying problems though with the Panasonic TV that I never had with the RCA, and I'd welcome some information.


I have the RCA DTC100 hooked up through the RCA VGA to component video adapter.

1. The TV always defaults to a 16:9 aspect ratio, even though the TV, picture source (satellite or local broadcast),and satellite box are 4:3. You can manually go into the menu and change this each time you turn the TV on, but it's a mess. Panasonic told me there is nothing they can do to make sure the TV senses the right aspect ratio or that it "remembers" the aspect ratio that you entered when you turn the TV on the next time.


I am thinking about buying a new HDTV box, but I'm not sure that would solve the problem. The output of the DTC100 is a 1080i output, which is inherently 16:9. Some of the other satellite boxes allow you to choose different outputs, such as 720P or 480P, but those should also be a 16:9 aspect ratio inherently as well, correct??? - causing the TV to still default to the incorrect aspect ratio when watching standard definition TV.


- Does anyone know whether any of the other HDTV boxes, with component video outputs and selectable outputs, would work any differently, or would I still have to change the aspect ratio of the TV each time?

-Does anyone know how to "hard-code" the TV, through the service menu or otherwise, to only be a 4:3 aspect ratio on the first input?


2. The second problem I've had with the DTC100/Panasonic combo is that when viewing certain pictures (especially when viewing a true HDTV picture) that has a substantial difference between a dark part of the picture and a bright part of the picture, such as a landscape/sky picture, the edges of the picture, right around the transition of the light/dark objects, starts waving around and shrinking from both sides of the TV edge by a couple of inches or more. The rest of the picture looks fine, and the center part of the lines that are shrinking look fine - it's just that one part of the picture that has a problem.


I've adjusted the raster on the DTC100, and I've messed with the screw on the VGA converter box, with no luck. The raster made it worse, and the screw on the converter box only shifted the picture left or right, while still maintaining the wavy edge.


- Does anyone have any suggestions of things I could try to adjust to resolve this?

- Is this a common phenomenon, and is there a name for this?
 

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Phil,


First of all, sorry you are having some problems with your new purchase.


If you get another set-top box like the new Sony SAT-200HD or the Samsung TS-165 (both model numbers are close...can't remember off the top of my head) you can specify 480p output. If you do that, your Panasonic will default to 4:3 because it will not do 16:9 for 480p like last year's model. The drawback is your obvious loss of resolution 1080 down to 480p.


The second issue sounds like poor EHT compensation, or local high voltage regulation. In other words, part of the screen breathes with changes in light output. If this is the case, you can try increasing the east-west (horizontal) width of the picture in the service menu. This will reduce the chance of seeing so much of the bending and breathing. Again, the drawback here will be cropping of the picture and losing some content. As for how common this is, with the larger CRTs 36v-40v, it can be noticeable depending on two things. the first is how much money the manufacturer spent in their power supply, and the second, how well they hide the deficiencies.
 

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Discussion Starter · #3 ·
Thanks for the info Spencer.


I was beginning to come to the conclusion that I might just have to live with manually changing the aspect ratio everytime I turn the TV on. I just can't understand why Panasonic doesn't allow you to hard code it.... Sounds like somebody wasn't thinking too much when they designed it....


On the second topic, can you explain EHT compensation and/or local high voltage regulation. What is EHT compensation, and by "local" do you mean inside the TV, or my local power company's supply? Why would either affect the width of the picture? Does it have something to do with higher power needed to display bright pictures, and the power source can't keep up with the variation? Is there an article on this anywhere that might give a detailed explanation?


I'm an Electrical Eng, but I'm lost when it comes to TV's.... If your answers are technical, I should still be able to follow it.


Thanks,

Phil
 

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The set will do the squeeze for 1080i signals but not for DVD. Maybe ther is something in the loop that is making your set think it's getting 1080i which is why it is in squeeze mode (16x9).


Wait a minute... the RCA DTC100 is a STB HDTV receiver isn't it? Then it is working correctly. Since HDTV is generally 16x9, you should be seing everything the way it is supposed to be seen. Does the aspect look off to you? Have you tries setting the receiver to 16x9. That should work.
 

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Discussion Starter · #5 ·
I believe the problem is that the DTC100 outputs a 1080i that is not a true widescreen format. When the TV is in 16:9 vs. 4:3, the picture is squeezed vertically, i.e. letterboxed, when it should fill out the whole screen vertically. If you manually change the TV to the 4:3, then the picture is at it should be - no letterboxes and no chopping of the picture horizontally or vertically.


If you change the DTC100 to 16:9 (assuming a HD signal is being received), while keeping the TV at 16:9, the result is a letterboxed letterbox, i.e. both the TV and the DTC100 are adding seperate letterboxes which results in a very small vertical picture.


Phil
 

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Phil-


I have a Panny CT32HX-41 and Panny TUHDS-20 STB and see the same thing (I think) you do when viewing HDTV material in 16:9 mode. What happens is that at the top of the picture between the black letterbox and the sky (or other bright/white colors at the top of the picture), the picture apprears to "jiggle" on the line between the black bar and actual picture. This is starting to cause me to keep the box on 480P so I don't see it.


Don't know what is causing this, have tried different component cables (Monster etc..) and also am using a Panamax surge/conditioner, so I'm pretty much clueless as to how to get it corrected. I've not tried to calibrate the set with my Avia disk yet, maybe that is something I should look at....
 

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I can't add much to this thread as most of you know my views toward old analog versus modern wide screen HDTV. I will add this though I also have a DTC-100 in my HDTV yet I can get the 4:3 foolscreen using the DTC-100. Only when using a interlaced DVD player. I can't get 4:3 foolscreen when I am using 1 of 3 progressive scan DVD players, it locks in a wide mode. :)



P.S. Although I have never used the 4:3 foolscreen format for a full program, I continually snoop to see what I can and can't do with this HDTV.
 

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Phil-


The Avia "Guide To Home Theater" DVD is a great disk to set-up any home theater! Search Google under "Avia" and you should be able to get a pretty good price on the disk, usually about $35 or so.


The disk allows you to fine-tune your audio and your video to get the most out of your system. You will also need an ANALOG sound meter, such as the one by Radio Shack to make the audio adjustments. You can then adjust each speaker for your listening area, and in addition there are many subwoofer tests also to fine tune the sub. Worth every penny!


I have not used the video tests yet, but after reading some info. on the web today I have to do that immediately to get the best picture from my Tau. That may be the problem I am having with the "jiggles" since the black levels, contrast, etc... have not been adjusted. Many times the factory settings on these TV's are way outta whack to what they should be for normal viewing. I'll post again when I get the video adjusted and let ya know if it helped! Still love the colors on the Panasonic....
 

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Phil:


I have a set up similar to yours, with a DTC-100 and a Hitachi 36" HD-ready 36SDX01S TV.

I think I understand your aspect ratio problems and can help you work around it.


If your TV component input is setting itself to 16:9 aspect ratio, then your operation is the same as mine, except that I have RGB intead of component TV input for the DTC-100 connection and I have manually set that input for 16:9 aspect ratio.


My solution uses 2 separate connections between the DTC-100 and the TV. You may or may not like how it works, but it costs little or nothing to try.


Let's compare DTC-100 settings for screen format, etc.


The DTC-100 maintains two groups of some menu settings, one group for HD output mode and a separate group for non-HD output mode. The options are set while the DTC-100 is in the mode they affect, i.e., with HD output on, the settings affect HD output; with HD output off, the settings affect S-video/composite video and RF outputs.


Since you are currently using the HD output, let's review those options.

- Be sure HD is on.

- Enter main menu.

- Press '6' to select 'Preferences'

- Press '4' to select 'Screen Format'

- Move cursor/highlight to top field and press 'Select' to choose '16:9 Widescreen'

- Move cursor down and select 'Normal' (to see 4:3 in proper aspect ratio)

- Press 'Clear' (or 'Exit' on some remotes) to leave menu.


This sets up the HD ouptut mode (16:9) to match the component input mode (16:9) of the TV.


Next, add an S-video (preferred) or composite video connection from the DTC-100 to an appropriate TV input.


Turn HD off on the DTC-100 and switch the TV input to the one you plugged the new cable into. You should have a picture from the DTC-100.


Now to set up the DTC-100 for this mode:


- Be sure HD is off.

- Enter main menu.

- Press '6' to select 'Preferences'

- Press '4' to select 'Screen Format'

- Move cursor/highlight to top field and press 'Select' to choose '4:3 Standard'

- Move cursor down and select 'Letterbox' (to display 16:9 in proper aspect ratio)

- Press 'Clear' (or 'Exit' on some remotes) to leave menu.


You now have 2 separate modes for your DTC-100/TV combination.


For HDTV program viewing, turn DTC-100 HD on and select the component input on the TV. The DTC-100 will send the 1080i signal (vertically stretched) to the TV, which will vertically compress the signal to provide highest resolution 16:9 viewing. In this mode, a 4:3 program transmitted within an HDTV signal will be reduced in size and have black or gray borders around it. To expand this reduced 4:3 picture to fill the screen you have to use the other mode (below).


For full screen SDTV program viewing, turn DTC-100 HD off and select the appropriate video input on the TV. The DTC-100 will automatically fill the TV screen for NTSC and 4:3 SDTV signals. HDTV signals will automatically be letterboxed by the DTC-100 to display as 16:9 on the TV, but not at full resolution. For a 4:3 picture transmitted within an HDTV signal in this mode, you have the option of watching the reduced size as above (Letterbox) or full screen (Cropped). You can toggle between these settings using the 'Forward' key on the remote.


This arragement works for us. Maybe it will work for you, since your component input seems to always lock into 16:9 mode with a 1080i or 540p input from the DTC-100.
 
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