- We may have Color TV within another decade. - 5 Updates
- Cleaning rubber rollers - 3 Updates
- Ray-49e VHF receiver not receiving - 2 Updates
| granpa78@dontask.com: Oct 25 03:00PM -0400 Since the beginning of television, people have dreamed about seeing a color image on their picture tube. Scientists and engineers have been working on this for years, and it appears that in another decade or so, we may begin seeing COLOR TV. Until then, there are some colored cellophane filters that can be taped to the front of the screen on any black and white tv, which makes the picture appear colored, but it's not actual matched color. Personally, I have watched black and white television for so many years, that I will probably have a difficult time getting used to watching it in color, but the concept is appealing and fascinating. Yet, it's hard to imagine that the actual colors of images can be reproduced in life-like color at the speed that images are traced onto our picture tubes. I guess time will tell !!! |
| jurb6006@gmail.com: Oct 25 01:53PM -0700 And stereophonic sound ! Two actual separate channels ! Stay away from all that shit though or else cars will be running this rickety software called Windows and people will be able to hack into your brakes and steering via your tracking device. (that has actually happened) Eventually they will send a rocket to the moon, and then later forget how to build rockets. They will build things that simply cannot be fixed at any price. So stick with Madman Muntz and drive that Model T Ford. And that Philco radio on the kitchen table is enough for anybody. |
| Roger Blake <rogblake@iname.invalid>: Oct 26 01:22AM > Since the beginning of television, people have dreamed about seeing a > color image on their picture tube. It's inconceivable. Sounds like a lot of BS to make people unhappy with their current sets. I'll believe it when I see it. -- ----------------------------------------------------------------------------- Roger Blake (Posts from Google Groups killfiled due to excess spam.) NSA sedition and treason -- http://www.DeathToNSAthugs.com Don't talk to cops! -- http://www.DontTalkToCops.com Badges don't grant extra rights -- http://www.CopBlock.org ----------------------------------------------------------------------------- |
| "pfjw@aol.com" <pfjw@aol.com>: Oct 26 05:27AM -0700 > Stay away from all that shit though or else cars will be running this rickety software called Windows and people will be able to hack into your brakes and steering via your tracking device. (that has actually happened) > Eventually they will send a rocket to the moon, and then later forget how to build rockets. They will build things that simply cannot be fixed at any price. > So stick with Madman Muntz and drive that Model T Ford. And that Philco radio on the kitchen table is enough for anybody. Still playing that Tired Tune, eh? I guess from here on out, we are going to have to start calling you "Cassandra". It is knowledge that is never developed that is often deadlier than what is supposedly forgotten. Nor were the Luddites much more than an historical footnote. Peter Wieck Melrose Park, PA |
| MJC <gravity@mjcoon.plus.com>: Oct 26 04:50PM +0100 In article <c1e41960-3366-440f-b418-f565d230b1c0@googlegroups.com>, pfjw@aol.com says... > ... Nor were the Luddites much more than an historical footnote. I suppose all saboteurs could be called a footnote :-) Mike. |
| Jeff Liebermann <jeffl@cruzio.com>: Oct 25 01:11PM -0700 >are failing in the same way. I'm assuming they are not of the same batch >at manufacturing and then the same ageing failure but some gas or >biological vector moving about inside a casing Sorry, no clue. I have seen the problem, but simply assumed that there was some kind of gaseous attack on the rubber and that all the rubber parts were equally affected. This might offer a clue as to what is happening: <https://en.wikipedia.org/wiki/Tire_recycling#Tire_pyrolysis> However, I don't see how heating in an oxygen free environment explains the deterioration found in consumer electronics. I really wished that I knew the mechanism, because I could then make a fortune devulcanizing rubber automobile tires and recycling the resultant "goo" into new tires. <https://en.wikipedia.org/wiki/Vulcanization#Devulcanization> Incidentally, there are bacteria that eat rubber: <https://en.wikipedia.org/wiki/Vulcanization#Microbial_degradation> <http://www.rubbernews.com/article/19950710/ISSUE/307109993/tire-eating-bacteria-under-study> and eat other hydrocarbons (plastic, fuel, sewage, etc): <https://en.wikipedia.org/wiki/Microbial_corrosion> or the nightmare of having our plastics dominated civilization eaten alive by GMO bugs: <http://www.extremetech.com/extreme/224678-plastic-eating-bacteria-set-to-revolutionize-waste-disposal> <http://www.sciencealert.com/new-plastic-munching-bacteria-could-fuel-a-recycling-revolution> -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| "pfjw@aol.com" <pfjw@aol.com>: Oct 25 02:00PM -0700 On Tuesday, October 25, 2016 at 4:11:42 PM UTC-4, Jeff Liebermann wrote: > >are failing in the same way. I'm assuming they are not of the same batch > >at manufacturing and then the same ageing failure but some gas or > >biological vector moving about inside a casing Three things, from the most to least common, and depending on the composition of the material: a) Ozone - Ozone will attack both synthetic and natural rubber from neoprene to latex-based materials to a greater or lesser degree depending on various admixtures. Ozone is pretty much everywhere there are motors, electrical parts that switch on and off, lightening, automobiles, fuel-fired systems and more. b) UV - Any rubber material as above exposed to UV will gradually dry out, or even melt as the hardeners are compromised. Some materials are an amalgam of celluloid based components and rubber components that will also decay very quickly when exposed to UV. Remember celluloid doll heads and other toys shrinking and crumbling over time. c) Outgassing - many products made from natural and man-made materials, especially odd mixes as were commonly used 'back in the day' are prone to outgassing as well as some level of oxidation, even if not vulnerable to UV or Ozone. The most obvious of these is Catalin, a pre-Bakelite product that is made from the same basic ingredients, but without the aggregates (typically carbon-black, lignen (sawdust) and other stabilizers. Many soft rubbers used as platens were made from specialized mixtures with peculiar admixtures to give them specific properties. Which evaporated over time - sometimes (as with catalin) a very, very long time. Chemical restorers attempt to undo/repair damage by replacing volatiles. That is about all that can be done without adding non-OEM materials. The ideal is to stay ahead of the damage rather than to try and recover once started. This, in some ways, is similar to White Metal disease, which is due to environmental exposure to trace amounts of such things as formaldehyde - present (back in the day) in insulation, glues, plywood and much more. It is a matter of specific material, types of exposure, local environmental conditions and several other factors, no single one being the single cause. Peter Wieck Melrose Park, PA |
| Jeff Liebermann <jeffl@cruzio.com>: Oct 26 07:48AM -0700 On Tue, 25 Oct 2016 14:00:49 -0700 (PDT), "pfjw@aol.com" >That is about all that can be done without adding non-OEM materials. >The ideal is to stay ahead of the damage rather than to try and >recover once started. Thanks for the detailed reply. I once found a paper that discusses rubber roller life in copier service. To obtain reliable operation, the oil impregnated in the roller must be maintained. It seems that the roller changes diameter when the oil is lost. The heat in the fuser section makes evaporation a serious problem. Here's a patent for one system for replacing the oil while the copier is running: "Oil secreting supply roller for an electrophotographic printer" <https://www.google.com/patents/EP1350142A2> While not a practical solution for turntables and tape machines, it might be adapted to laser printers. I found another article a few months ago on roller life versus roller oil content, but can't find it. maybe later. gotta run... -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| Jeff Liebermann <jeffl@cruzio.com>: Oct 25 01:33PM -0700 >><http://www.ebay.com/itm/200974082569> >while de soldering one of them, the case fall apart and find green >sign of oxidation inside, as described in the above link. The Icom radio I saw did not show any signs of corrosion. However, the cover was loose and wiggling it caused the signal to rise and fall dramatically. >This is a sort of blind repair (no schematic and no RF equipment). The Raymarine RAY49E is a fairly new product and should still be under warranty. Have you checked? Sorry, I couldn't find any schematics. >Is the LTM 450DW a correct replacement? I think it's the same part. Finding specs on the filter has not been very productive, so I can't compare data sheets. <https://www.aliexpress.com/item/20PCS-Radio-communication-machines-ceramic-filters-455KHZ-LTM455GW-5-feet-2-3-ceramic-crystal-5P/32357096260.html> I provided an eBay part that looks like an exact replacement: <http://www.ebay.com/itm/200974082569> Note that the listing shows that it's used in a wide variety of low end radios. Good enough methinks. More: <http://www.ebay.com/itm/261283232312> <http://www.dhgate.com/wholesale/m50fw+filter.html> The only problem is that there's no guarantee that the replacement part will be any better quality than the original. You might want to buy one or two from different vendors. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| 6dinopaoloREMOVE@gmail.com: Oct 26 09:19AM +0200 On Tue, 25 Oct 2016 13:33:46 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote: >The only problem is that there's no guarantee that the replacement >part will be any better quality than the original. You might want to >buy one or two from different vendors. I'll follows your suggestion to source parts from different supplier. Ciao, Dino |
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