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| Wuerstchenhund:
--- Quote from: timb on August 13, 2016, 01:57:07 pm ---The problem with CCFLs is they have a very finite life, while for the most part CRTs don't. --- End quote --- Of course CRTs have a finite life. The average 'half-time' of a CRT tube is around 20k hrs, after which the brightness will have fallen by 50%, and after which it will decline further. In addition, the lifetime is limited by some of its parts, i.e. the heater filament. CCFL tubes have a life span of somewhere in the range of 10k to 100k hrs. --- Quote ---(Though, to be fair, I hear some of the NuColor shutters also have a finite life due to bonding issues.) --- End quote --- This is just another issue on top. --- Quote ---Just because LCDs are a cheaper technology doesn't make them better. --- End quote --- LCD is not better because it's cheaper, it is better because it is the better performing technology. The fact that it's cheaper (these days, it wasn't back in the mid-90s) is just the bonus. --- Quote ---I personally think plasma TVs have much better pictures compared to LCD sets. Unfortunately it's an expensive technology that has heat and burnin issues, that's why it's basically dead. --- End quote --- Yes, and also because modern LCDs are much better than they were ten years ago. Plasma's strenght has been its superior reproduction of black, but that was back then. The price one paid for plasma, as you said, was fragility, heat/power consumption, and a very limited service life. --- Quote ---The NuColor display on the TDS series is capable of reproducing all 256 colors of the VGA palette pretty clearly, so I don't know why you're saying it's not capable of it? --- End quote --- What makes you think the TDS uses all 256 colors? From what I remember (OK, it's been a while) the UI itself uses just 16 out of 256 colors, and color grading I believe was limited to 16 or 32 colors. --- Quote ---I'd like to see that press release from Tek talking about NuColor being cheaper than a color CRT. For some reason I just can't imagine it being cheaper. --- End quote --- I don't have the original release but I managed to find this: http://www.electronicproducts.com/Test_and_Measurement/Oscilloscope_makers_ride_the_color_bandwagon.aspx ...The substantially lower cost of the NuColor display when compared with traditional shadow-mask displays played a big part in Tektronix being able to price the scopes so aggressively. Shadow-mask displays used in color DSOs (including their additional memory, power, and circuit needs) from Tektronix, Hewlett-Packard, and LeCroy in the past have added about $2,000 to $3,000 to the cost of a color scope. The estimated added costs with the NuColor display is only about $500 or so, according to Martinez. It shows that at least Tek believed it's cheaper to do NuColor than use a color CRT. --- Quote ---Hell, HP had been using color CRTs since the 80's on their logic analyzers. LeCroy had some of those big ass 1GHz scopes with color CRTs, mid to late 90's vintage, right? (The ones with the thermal printers; they replaced the models with Amber CRTs.) --- End quote --- Yes, but that doesn't show that color CRTs were cheaper. It shows that, at that time, LeCroy and HP thought that this is the appropriate technology for their digital scopes (and other kit in case of HP). Don't forget that in the digital scope market Tek suddenly found itself surrounded by much stronger competition than in the analog scope market (where Tektronix was pretty much the technology leader). --- Quote ---Keep in mind that NuColor wasn't originally designed for use on a raster scan display. It was designed to produce a color electrostatic CRT for analog oscilloscopes. (It also commanded a $1500 premium compared to the B&W only model when it was originally released in 1984!) --- End quote --- I can't remember about NuColor for analog scopes. What scope models was it used in, and what for? --- Quote ---For use on a scope, faced with the choice between: A) NuColor Display from 1995 B) Color CRT from 1995 C) Color LCD from 1995 I'll take A every single time, with B coming in second. In fact I'd take a monochrome CRT before I took option C! --- End quote --- In 1995 there was no big brand scope with color LCD I remember of. Which means for a 1995 scope I'd probably vote B over A, mainly because I would get a larger screen (the scopes with color CRT like the HP 54700 Series had a larger screens than the TDS series). NuColor would have given me more contrast but for a scope display that is pretty irrelevant, although NuColor would also give less flickering. Going forward to say 1998, I'd go for C every time. Even back then the readability and sharpness of a LCD like the ones used in the HP 545xxC, 546xxC or the LeCroy WR LT is *a lot* better than even a mono CRT or NuColor could ever provide. Colors might not be so overly saturated as on NuColor (but then, color saturation is was still great at least when the CCFL tube was new, it's only after many hours when the lamp has faded and shifted its color temperature that colors start looking washed out), but frankly for a scope I couldn't care less. As long as the display is clear, crisp and easily readable then it's fine. --- Quote ---I guess my point is, up until the early 2000's, LCDs were not a realistic option for oscilloscopes (yes, a few had them, but they were either absolute budget models with blurry monochrome LCDs or very high end models with clear yet expensive color displays). --- End quote --- Yes, but then the TDS700 wasn't exactly a bargain bin scope, too. Price-wise it very much did compete with the HP 545xx/546xx and 547xx, or the LeCroy LC 600 and WR LTs. In fact, some of the TFT equipped scopes were notabily cheaper than the TDS700 with NuColor. It may have saved Tek some money, but they certainly didn't pass that on to the customer. |
| dxl:
My TDS754 has a TFT, but only because i had to replace the NuColor Display. The Picture was almost invisible after the tube had being overdriven for 15 Years or so. That's one of the downsides on NuColor: The Shutter display 'eats' a certain amount of light, so Tek decided to crank up the brightness of the Tube which decreases it's life span. Another thing i never liked on the TDS700 series is the glossy shutter. Put the TDS700 in a Room where there's a window on the other side of the room. You have a reason to be happy every day when you have the Sun as Scope background ;) I don't have much devices from the 90s with color display. But i can say for sure that even the HP70004A display from my Spectrum Analyzer doesn't look bad compared to NuColor. But that display has a Sony Trinitron tube, which was probably way more expensive then a normal Color tube. |
| timb:
--- Quote from: Wuerstchenhund on August 13, 2016, 03:22:27 pm --- I don't have the original release but I managed to find this: http://www.electronicproducts.com/Test_and_Measurement/Oscilloscope_makers_ride_the_color_bandwagon.aspx ...The substantially lower cost of the NuColor display when compared with traditional shadow-mask displays played a big part in Tektronix being able to price the scopes so aggressively. Shadow-mask displays used in color DSOs (including their additional memory, power, and circuit needs) from Tektronix, Hewlett-Packard, and LeCroy in the past have added about $2,000 to $3,000 to the cost of a color scope. The estimated added costs with the NuColor display is only about $500 or so, according to Martinez. It shows that at least Tek believed it's cheaper to do NuColor than use a color CRT. --- Quote ---Keep in mind that NuColor wasn't originally designed for use on a raster scan display. It was designed to produce a color electrostatic CRT for analog oscilloscopes. (It also commanded a $1500 premium compared to the B&W only model when it was originally released in 1984!) --- End quote --- I can't remember about NuColor for analog scopes. What scope models was it used in, and what for? --- End quote --- The 5116 was the first use of Tek's NuColor technology. The purpose was to allow different channels to be displayed in different colors. (And for the readout to be color coded as well.) As for that article you linked, I imagine a lot of that cost they estimate was in the memory itself (which would have been hundreds of dollars per MB in the early to mid 90's), but I don't see why a color CRT would require any more memory than a NuColor display? The power requirements should be similar as well. It would need additional circuitry, but so does the NuColor shutter! After thinking about it, I guess a small color CRT could have been expensive to produce. Most color TVs started out at 13" and color monitors at 12" so going below that would have increased cost, especially since they didn't have the economy of scale to bring the cost down. By that time Tek would have been making the NuColor shutter for over 10 years, so $500 seems like a reasonable figure. I just think it was an interesting technology. Re: TDS color depth... I don't think the TDS displays more than 20 different colors on the screen at any one time; however each color can be selected from any in the VGA palette. You can go into the display menu and scroll through the color list to see for yourself. This isn't a limit of the NuColor hardware, there's just no need to display more than that on this particular scope. The proof that the hardware is capable of a full color gamut is evident when you look at other products using the technology: Tek made a NuColor computer monitor; JVC made portable color video monitors using the NuColor system, which is capable of displaying any color a normal color CRT TV can. I do agree the technology is a dead end now and LCDs are clearly better, but like I said earlier, it's fun to speculate what if. I think, as another poster mentioned, the big disadvantage to them is how much light the shutters eat up, requiring you to overdrive the CRT. It's a shame as with 10 more years of development, I think they could have improved on that a lot. Ah well. Oh, one more thing. Even a modern LCD still struggles to get the black levels of a 10 year old plasma. I also imagine they could have corrected a lot of the deficits, had it continued to be developed like LCDs have. No display technology that needs a backlight will ever be as good as one that produces its own light. Period. That's why I'm keeping my fingers cross and waiting for OLED sets to be perfected before I replace my plasma. Edit: I almost wonder if the reason I like the NuColor display so much is because of the high refresh rate, which eliminates the 60Hz flicker found on most other raster scan style CRTs of the era. (I had to run my gaming monitor at 85Hz, minimum.) |
| siggi:
--- Quote from: timb on August 13, 2016, 10:16:21 pm ---The 5116 was the first use of Tek's NuColor technology. --- End quote --- Wow, that was a pretty fun read. Toward the end it says "As time goes on then, it is reasonable to assume that the color shutter will be used in a wide variety of products and applications.". Even as the cover photo in the article demonstrates how the trace intensity is skewered by the LCD shutter :). |
| Jwalling:
--- Quote from: siggi on August 13, 2016, 10:46:16 pm --- --- Quote from: timb on August 13, 2016, 10:16:21 pm ---The 5116 was the first use of Tek's NuColor technology. --- End quote --- Wow, that was a pretty fun read. Toward the end it says "As time goes on then, it is reasonable to assume that the color shutter will be used in a wide variety of products and applications.". Even as the cover photo in the article demonstrates how the trace intensity is skewered by the LCD shutter :). --- End quote --- +1 I had no idea that this technology was around in 1984. I have fond memories (no pun intended) of both Radio Electronics and Popular Electronics. (Still have a bunch of the old magazines) I especially remember the Cosmac Elf 1802 project - my first (big) project I ever did; don't remember what happened to it, but wish I kept it... I always loved the back pages with all the surplus sellers such as PolyPaks, etc. EDIT: Link https://en.wikipedia.org/wiki/COSMAC_ELF Mine didn't look that nice, though :) Jay |
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