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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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JVC 55" Rear-projection TV
Our 18 year-old rear projection TV (JVC 55" Letter-box) has finally failed...
or not quite... the blue sweep only, dips dramatically in the upper middle of the screen making for some garish looking pictures... particularly on old B&W Hitchcock re-runs (playing here w/o commercials ;-) So I bought a 55" LCD (LED-backlit) at 1/4 the price of the original. The new set weighs 40#, the old one is so heavy I can barely lift one end. I had visions of throwing it on my pick-up truck and taking it to this weekend's hazardous waste at the local park. But I'd need a couple of moving-company-strength assistants. Anyone here in Arizona want it? If not I'll bust it up and dispose in liftable chunks. Also listed at... http://phoenix.craigslist.org/evl/ele/2994884637.html Contact info in the sig... ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
#2
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JVC 55" Rear-projection TV
Throw in on craigslist or whatever and get fifty bucks or something
for it. Or even give it away. It has a convergence problem and can be fixed. But if you bust it up you them waste the pollution caused to build the thing. Plus the fact that those things are ten times more reliable than the new stuff so someone without alot of money could have it for a while. T |
#3
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JVC 55" Rear-projection TV
Here it is, broken open, a couple of hidden screws "assisted" by force ;-)
http://www.analog-innovations.com/SED/Gutted_JVC.jpg Anything there worth saving? I see some nice heatsinks. The "screen" _is_ a grating (Fresnel?). Is that worth anything? ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
#4
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
Here it is, broken open, a couple of hidden screws "assisted" by force ;-)
http://www.analog-innovations.com/SED/Gutted_JVC.jpg Anything there worth saving? I see some nice heatsinks. The "screen" _is_ a grating (Fresnel?). Is that worth anything? ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
#5
Posted to sci.electronics.design,sci.electronics.basics,sci.electronics.repair
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JVC 55" Rear-projection TV
Jim Thompson wrote:
Here it is, broken open, a couple of hidden screws "assisted" by force ;-) http://www.analog-innovations.com/SED/Gutted_JVC.jpg Anything there worth saving? I see some nice heatsinks. The "screen" _is_ a grating (Fresnel?). Is that worth anything? It'd make a bodacious oscilloscope for your local technical museum. --Winston |
#6
Posted to sci.electronics.design,sci.electronics.repair
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JVC 55" Rear-projection TV
On May 7, 10:32*am, Jim Thompson To-Email-Use-The-Envelope-I...@On-My-
Web-Site.com wrote: Here it is, broken open, a couple of hidden screws "assisted" by force ;-) * * *http://www.analog-innovations.com/SED/Gutted_JVC.jpg Anything there worth saving? I see some nice heatsinks. The "screen" _is_ a grating (Fresnel?). *Is that worth anything? * * * * * * * * * * * * * * * * * * * *...Jim Thompson -- | James E.Thompson, CTO * * * * * * * * * * * * * *| * *mens * * | | Analog Innovations, Inc. * * * * * * * * * * * * | * * et * * *| | Analog/Mixed-Signal ASIC's and Discrete Systems *| * *manus * *| | Phoenix, Arizona *85048 * *Skype: Contacts Only *| * * * * * * | | Voice480)460-2350 *Fax: Available upon request | *Brass Rat *| | E-mail Icon athttp://www.analog-innovations.com| * *1962 * * | I love to cook with wine. * * Sometimes I even put it in the food. * * * * * * * * * * * * * * * * * * * *...Jim Thompson -- | James E.Thompson, CTO * * * * * * * * * * * * * *| * *mens * * | | Analog Innovations, Inc. * * * * * * * * * * * * | * * et * * *| | Analog/Mixed-Signal ASIC's and Discrete Systems *| * *manus * *| | Phoenix, Arizona *85048 * *Skype: Contacts Only *| * * * * * * | | Voice480)460-2350 *Fax: Available upon request | *Brass Rat *| | E-mail Icon athttp://www.analog-innovations.com| * *1962 * * | I love to cook with wine. * * Sometimes I even put it in the food. Copper is just NOT that expensive yet. And, don't see any gold. |
#7
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
Jim Thompson wrote:
Here it is, broken open, a couple of hidden screws "assisted" by force ;-) http://www.analog-innovations.com/SED/Gutted_JVC.jpg Anything there worth saving? I see some nice heatsinks. The "screen" _is_ a grating (Fresnel?). Is that worth anything? ...Jim Thompson Hook up wire from the harness. :-) Ed |
#8
Posted to sci.electronics.design,sci.electronics.basics,sci.electronics.repair
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JVC 55" Rear-projection TV
On May 7, 10:32*am, Jim Thompson To-Email-Use-The-Envelope-I...@On-My-
Web-Site.com wrote: Here it is, broken open, a couple of hidden screws "assisted" by force ;-) * * *http://www.analog-innovations.com/SED/Gutted_JVC.jpg Anything there worth saving? I see some nice heatsinks. The "screen" _is_ a grating (Fresnel?). *Is that worth anything? * * * * * * * * * * * * * * * * * * * *...Jim Thompson snip And don't tell me, the new set picture is MASSIVELY better than the old one even on its best day. Try Craig's list and then dismantle it. RIP JVC. Why didn't you replace it sooner? G² |
#9
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On 5/7/2012 12:32 PM, Jim Thompson wrote:
Here it is, broken open, a couple of hidden screws "assisted" by force ;-) http://www.analog-innovations.com/SED/Gutted_JVC.jpg Anything there worth saving? I see some nice heatsinks. The "screen" _is_ a grating (Fresnel?). Is that worth anything? ...Jim Thompson http://www.ebay.com/itm/49-FRESNEL-L...em2a1c02 1708 $80.00 http://www.ebay.com/itm/38X24-SOLAR-...em27c5d1 0b13 $34.00 http://www.ebay.com/itm/56-FRESNEL-L...em27c551 aca7 $97.50 That's going three pages deep on ebay. Some have a frame built and installed. Mikek |
#10
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On Mon, 07 May 2012 23:57:09 -0400, ehsjr wrote:
Jim Thompson wrote: Here it is, broken open, a couple of hidden screws "assisted" by force ;-) http://www.analog-innovations.com/SED/Gutted_JVC.jpg Anything there worth saving? I see some nice heatsinks. The "screen" _is_ a grating (Fresnel?). Is that worth anything? ...Jim Thompson Hook up wire from the harness. :-) Ed Full knock-down... http://www.analog-innovations.com/SE..._KnockDown.pdf They don't make them like that anymore. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
#12
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
Jim Thompson wrote: Full knock-down... http://www.analog-innovations.com/SE..._KnockDown.pdf They don't make them like that anymore. Maybe an astronomy club would want those lenses. -- Reply in group, but if emailing add one more zero, and remove the last word. |
#13
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On 09/05/2012 20:19, Tom Del Rosso wrote:
Jim Thompson wrote: Full knock-down... http://www.analog-innovations.com/SE..._KnockDown.pdf They don't make them like that anymore. Maybe an astronomy club would want those lenses. They would be nothing like diffraction limited or monochromatic so the best bet is to donate them to the scouts for fire starting with the sun. -- Regards, Martin Brown |
#14
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On Wed, 9 May 2012 15:19:55 -0400, "Tom Del Rosso"
wrote: Jim Thompson wrote: Full knock-down... http://www.analog-innovations.com/SE..._KnockDown.pdf They don't make them like that anymore. Maybe an astronomy club would want those lenses. I suspected they might be good for something. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
#15
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On Wed, 09 May 2012 13:31:30 -0700, Jim Thompson
wrote: On Wed, 9 May 2012 15:19:55 -0400, "Tom Del Rosso" wrote: Jim Thompson wrote: Full knock-down... http://www.analog-innovations.com/SE..._KnockDown.pdf They don't make them like that anymore. Maybe an astronomy club would want those lenses. I suspected they might be good for something. ...Jim Thompson Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
#16
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. -- You can't have a sense of humor, if you have no sense. |
#17
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On Wed, 09 May 2012 16:39:51 -0400, "Michael A. Terrell"
wrote: Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. And optical interface between CRT face and lens... cute! ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
#18
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
Jim Thompson wrote: On Wed, 09 May 2012 16:39:51 -0400, "Michael A. Terrell" ? wrote: ? ?Jim Thompson wrote: ?? ?? Note that there are only two CRT's shown... the third was the failure ?? mechanism... leaking oil ;-) ? ? ? Glycol based coolant. That was a common failure, and fairly easy to ?fix. And optical interface between CRT face and lens... cute! Another problem with it was something growing in the coolant, witch causes it to run hotter, and affecting the focus or having a dim area in that color. -- You can't have a sense of humor, if you have no sense. |
#19
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
Michael A. Terrell wrote: Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. Too late now. -- Reply in group, but if emailing add one more zero, and remove the last word. |
#20
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
Tom Del Rosso wrote: Michael A. Terrell wrote: Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. Too late now. Some people never do any P.M. ;-) -- You can't have a sense of humor, if you have no sense. |
#21
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
Michael A. Terrell wrote: Tom Del Rosso wrote: Michael A. Terrell wrote: Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. Too late now. Some people never do any P.M. ;-) Preventive maintenance on a picture tube? I tried fixing a TV from the 90's once. I'm sure I could have done it, if it had been the least bit designed for mantenance. The damned back and bottom were molded together, so if you took off the back then it had no bottom (or support for the board, which was left dangling) and it kept threatening to fall back and crack the neck off. I decided it wasn't worth the bother or danger. -- Reply in group, but if emailing add one more zero, and remove the last word. |
#22
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
Tom Del Rosso wrote: Michael A. Terrell wrote: Tom Del Rosso wrote: Michael A. Terrell wrote: Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. Too late now. Some people never do any P.M. ;-) Preventive maintenance on a picture tube? On tube type TVs. I did that for about nine months, in the US Army. They were used as video monitors/TVs in classrooms & Air Traffic Control Towers. where you wanted them to work to their design. Since those projection CRTS are know to leak after so many years, what is wrong with replacing them before they fail and damage the circuit boards? I tried fixing a TV from the 90's once. I'm sure I could have done it, if it had been the least bit designed for mantenance. The damned back and bottom were molded together, so if you took off the back then it had no bottom (or support for the board, which was left dangling) and it kept threatening to fall back and crack the neck off. I decided it wasn't worth the bother or danger. It isn't that difficult, if you really want to fix one. That problem didn't start in the '90s, and was done on computer monitors as well. -- You can't have a sense of humor, if you have no sense. |
#23
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On Thu, 10 May 2012 01:33:44 -0400, "Tom Del Rosso"
wrote: Michael A. Terrell wrote: Tom Del Rosso wrote: Michael A. Terrell wrote: Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. Too late now. Some people never do any P.M. ;-) Preventive maintenance on a picture tube? I tried fixing a TV from the 90's once. I'm sure I could have done it, if it had been the least bit designed for mantenance. The damned back and bottom were molded together, so if you took off the back then it had no bottom (or support for the board, which was left dangling) and it kept threatening to fall back and crack the neck off. I decided it wasn't worth the bother or danger. Same here. The only easy access was to that alignment board (with those ~100 pots and the backside of the CRT's... the rest was accessible only by disassembly of the particle-board-bonded-vinyl case. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
#24
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On 5/10/2012 11:07 AM, Jim Thompson wrote:
On Thu, 10 May 2012 01:33:44 -0400, "Tom Del Rosso" wrote: Michael A. Terrell wrote: Tom Del Rosso wrote: Michael A. Terrell wrote: Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. Too late now. Some people never do any P.M. ;-) Preventive maintenance on a picture tube? I tried fixing a TV from the 90's once. I'm sure I could have done it, if it had been the least bit designed for mantenance. The damned back and bottom were molded together, so if you took off the back then it had no bottom (or support for the board, which was left dangling) and it kept threatening to fall back and crack the neck off. I decided it wasn't worth the bother or danger. Same here. The only easy access was to that alignment board (with those ~100 pots and the backside of the CRT's... the rest was accessible only by disassembly of the particle-board-bonded-vinyl case. ...Jim Thompson Have you melted any coins or started a fire yet with the Fresnell lens? Wear two pairs of sun glasses or some cutting goggles, the hot spot is extremely bright. Mikek |
#25
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On Thu, 10 May 2012 13:26:49 -0500, amdx wrote:
On 5/10/2012 11:07 AM, Jim Thompson wrote: On Thu, 10 May 2012 01:33:44 -0400, "Tom Del Rosso" wrote: Michael A. Terrell wrote: Tom Del Rosso wrote: Michael A. Terrell wrote: Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. Too late now. Some people never do any P.M. ;-) Preventive maintenance on a picture tube? I tried fixing a TV from the 90's once. I'm sure I could have done it, if it had been the least bit designed for mantenance. The damned back and bottom were molded together, so if you took off the back then it had no bottom (or support for the board, which was left dangling) and it kept threatening to fall back and crack the neck off. I decided it wasn't worth the bother or danger. Same here. The only easy access was to that alignment board (with those ~100 pots and the backside of the CRT's... the rest was accessible only by disassembly of the particle-board-bonded-vinyl case. ...Jim Thompson Have you melted any coins or started a fire yet with the Fresnell lens? Wear two pairs of sun glasses or some cutting goggles, the hot spot is extremely bright. Mikek I haven't tried it yet. But it's not circular... JVC calls it "lenticular". http://en.wikipedia.org/wiki/Lenticular_lens It's what I would call a "grating". So I'd guess it would focus a line rather than a spot. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
#26
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On 5/10/2012 1:39 PM, Jim Thompson wrote:
On Thu, 10 May 2012 13:26:49 -0500, wrote: On 5/10/2012 11:07 AM, Jim Thompson wrote: On Thu, 10 May 2012 01:33:44 -0400, "Tom Del Rosso" wrote: Michael A. Terrell wrote: Tom Del Rosso wrote: Michael A. Terrell wrote: Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. Too late now. Some people never do any P.M. ;-) Preventive maintenance on a picture tube? I tried fixing a TV from the 90's once. I'm sure I could have done it, if it had been the least bit designed for mantenance. The damned back and bottom were molded together, so if you took off the back then it had no bottom (or support for the board, which was left dangling) and it kept threatening to fall back and crack the neck off. I decided it wasn't worth the bother or danger. Same here. The only easy access was to that alignment board (with those ~100 pots and the backside of the CRT's... the rest was accessible only by disassembly of the particle-board-bonded-vinyl case. ...Jim Thompson Have you melted any coins or started a fire yet with the Fresnell lens? Wear two pairs of sun glasses or some cutting goggles, the hot spot is extremely bright. Mikek I haven't tried it yet. But it's not circular... JVC calls it "lenticular". http://en.wikipedia.org/wiki/Lenticular_lens It's what I would call a "grating". So I'd guess it would focus a line rather than a spot. ...Jim Thompson I think you will find two layers, they come apart, one just lays over the other, one is a grating the other will be a Fresnell lens. The grating is on the viewing side the Fresnell is on the inside. Be careful where you store it, I'll bet there has been a fire somewhere from poor placement of a large Fresnell lens. Mikek |
#27
Posted to sci.electronics.design,sci.electronics.basics,alt.binaries.schematics.electronic,sci.electronics.repair
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JVC 55" Rear-projection TV
On 5/10/2012 1:53 PM, amdx wrote:
On 5/10/2012 1:39 PM, Jim Thompson wrote: On Thu, 10 May 2012 13:26:49 -0500, wrote: On 5/10/2012 11:07 AM, Jim Thompson wrote: On Thu, 10 May 2012 01:33:44 -0400, "Tom Del Rosso" wrote: Michael A. Terrell wrote: Tom Del Rosso wrote: Michael A. Terrell wrote: Jim Thompson wrote: Note that there are only two CRT's shown... the third was the failure mechanism... leaking oil ;-) Glycol based coolant. That was a common failure, and fairly easy to fix. Too late now. Some people never do any P.M. ;-) Preventive maintenance on a picture tube? I tried fixing a TV from the 90's once. I'm sure I could have done it, if it had been the least bit designed for mantenance. The damned back and bottom were molded together, so if you took off the back then it had no bottom (or support for the board, which was left dangling) and it kept threatening to fall back and crack the neck off. I decided it wasn't worth the bother or danger. Same here. The only easy access was to that alignment board (with those ~100 pots and the backside of the CRT's... the rest was accessible only by disassembly of the particle-board-bonded-vinyl case. ...Jim Thompson Have you melted any coins or started a fire yet with the Fresnell lens? Wear two pairs of sun glasses or some cutting goggles, the hot spot is extremely bright. Mikek I haven't tried it yet. But it's not circular... JVC calls it "lenticular". http://en.wikipedia.org/wiki/Lenticular_lens It's what I would call a "grating". So I'd guess it would focus a line rather than a spot. ...Jim Thompson I think you will find two layers, they come apart, one just lays over the other, one is a grating the other will be a Fresnell lens. The grating is on the viewing side the Fresnell is on the inside. Be careful where you store it, I'll bet there has been a fire somewhere from poor placement of a large Fresnell lens. Mikek Hey Jim, did you find a Fresnell in the 55" tv? Mikek |
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