Tuesday, 22 July 2014

Fernseher aus Berlin - Nr. 5

Well, I've been in Berlin for over three weeks now and I've already got too much too report... already falling behind with sharing my discoveries here.

I've collected five SCART TVs so far but I'm not going to start my Berlin with TV #1. Instead, I'll start where I'm currently working...

I picked up this (apparently) defective Loewe for it's tube only. This is a 100 Hz television and you're about to see why 100 Hz processing sucks dogs balls when it comes to retrogaming. However, the tubes used in the later model Loewes are stellar when combined with an older, analog chassis.

Before I gut this unit and chunk all but the tube, I figured I'd take the opportunity to show exactly why 100 Hz is so damn awful.

Before we get to the nasty stuff, here are some details on the unit in questions:

Loewe. Profil 3570 Z
100 Hz/Blackline
Chassis type: Q4400
Tube sticker
Tube type: A66EAK552X54
Also, I should mention that the collection of this SCART television was rather memorable. I turned up at Micheal's house (the eBay seller) with my hand cart, ready to cart this thing back on the subway. Instead, Michael loaded the TV, my trolley and myself into his car and drove me across Berlin back to my apartment. What an awesome guy!

Okay, now let my try to explain the worst that 100 Hz processing has to offer...

Red on Black

This is probably the most obvious place to start when going on a 100 Hz hate fest.

In the following example, I photographed the Taito logo from Rainbow Islands with 9 different color settings (i.e. the color balance setting in the TV's picture menu). I started with color at minimum (value of 0) and worked up to the maximum (value of 63) in steps of 8. As you'll see, the greater the color intensity, the greater the visual distortion of the Taito logo.

Note: I placed a small sticker on the glass of the tube and focused my camera at this point for each image. You can see the sticker stays in focus, assuring you that my camera wasn't simply out of focus in the later images.

Color = 00
Color = 07
Color = 15
Color = 23
Color = 31
Color = 39
Color = 47
Color = 55
Color = 63
Ouch! What a mess!

Now, did you notice how the white "CORPORATION" text stayed crisp while the red became over saturated and distorted? It took me a long time to realise that the artifacts created by by 100 Hz processing where exacerbated by the color balance setting. Later I discovered that the color balance on most SCART TVs doesn't have any effect on the incoming RGB signal. In my mind, this is a good thing. The signal passes untouched.

So, with the color set to a low value, the image is sharp and not too distorted. The problem is, of course, that then the image looks washed out and loses that classic CRT vibrancy.

When I first started out with an 80+ cm Loewe unit with a Q4400 it was very frustrating to see these artifacts. I thought maybe my my particular unit was defective or there was something wrong with my homemade VGA to SCART cable. As it was pointed out to me on a forum, the problem lies with the 100 Hz processing.

Further examples

Next, let's check out a random assortment of gruesome 100 Hz pixel murders, starting with a bunch of Rainbow Island examples:

Note the "Focus!" sticker... it's sharp! Also, white stays true.
Red on Black = Disaster
Everything is going wrong here...
Oh my... look at the ghosting!
Compare the clarity of the white text compared with the manic colors
Notice the random lines coming from the A and D characters?!
More icky red text
Check out the color distortion in the text!
Observe the distorted rainbow
Willow's title text suffering from 100 Hz processing
Check out the edges of the "Game Over" rectangle...
Street Fighter II loses its crispness
We could go on all night finding more disastrous examples of this kind of built-in image processing. It's a real shame because the focus, stability and overall clarity of this TV is amazing.

Conclusion

100 Hz. Don't do it! Unless the 100 Hz television your neighbor is giving away also has a VGA port (which would most likely bypass this digital processing debacle) or has a tube your want to plunder, say "thanks but no thanks". It's just not worth the disappointment.

And, it gets worse. The images I've shown are bad enough but seeing what this processing does to animation is just awful... I'll see if I can capture some video for a future installment.

11 comments:

  1. Are the 100hz tubes compatible with 50/60Hz chassis? I would've thought they wouldn't support 15Khz, unless you are going to swap the yoke over too?

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  2. Yes, correct. I swapped over the yoke from the old tube. Really easy to do with these Philips EAK66 tubes.

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  3. Thanks, given the rarity of Grundig TVs here in Western Australia, I think I'm not going to have too much luck finding a donor analog chassis .. was secretly hoping a Jomac chassis would work with the 100Hz yoke but I'm thinking that's not going to work.

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  4. Oh, so you already have one of these tubes? I would happily send you an older yoke... I have plenty spare here in Berlin!

    The other option is a Hantarex chassis that is designed to used these tubes (with the 100 Hz yoke). That's the direction I'll go if I can find one of these tubes in New Zealand (where I'll be returning to).

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  5. Oh, so you already have one of these tubes? I would happily send you an older yoke... I have plenty spare here in Berlin!

    The other option is a Hantarex chassis that is designed to used these tubes (with the 100 Hz yoke). That's the direction I'll go if I can find one of these tubes in New Zealand (where I'll be returning to).

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  6. One of the first Loewes I got was a Calida 5772 with a q2500 chassis. Tube looks really good but has 100hz processing. I haven't pulled the back to see what tube it has yet. I found an e3000 TV shortly after and this TV had been a backup since. With an analogue chassis I think it will topple the e3000.

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  7. Ah, yes. The 72 cm Philips tubes are pretty nice, hey? Mostly flat with a slight curve, nice dark screen.

    I have tried connecting Grundig CUC 5630 and CUC 4630 chassis to the A68ESF tubes but the image was always too wide. The chassis need modification to work with such a tube.

    I don't know if any arcade chassis were made to work with these tubes but it would be amazing if they were...

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  8. What about Joey's "universal" chassis? Would still need a compatible yoke though, and it is a bit costly. I know you had issues with geometry before, one luxury I do have is his workshop is only 20 mins away from me.

    My only hesitation with going down the universal chassis route is I'm guessing I will lose the ability to display composite video/svideo. Yeah I know it's horrible compared to RGB, but I'm not too keen on spending the money modifying my NES or N64 to output RGB.

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  9. Hi there! Considerung you once listed that model I wanted to ask, if a Contur 770 would be worth picking up if a modification isn't an option. I already got a small Loewe Concept Plus with a really great picture concerning sharpness but with a horrid geometry and wanted to know, how the 770 would probably compare to it.

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  10. I reckon a Contur 770 would be great! The one I had looked excellent.

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