I just “inherited” a 51" Hitachi projection HDTV (#51F510) that has a dimming screen. :edit: Jay’s right - no bulbs, only 3 guns. One gun failing apparently will cause a color shift, not a fade.
Now I’m scratching my head…
TIA :tup:
Sounds like an old school rear projection HDTV like I have, in which case it isn’t a single bulb it’s 3 color guns. Each bulb will be $200+ even if you find a deal on them. Single easily replaced bulbs are in the new DLP sets.
Might be better off just taking it apart and seeing what you can clean up. Chances are the color gun lenses have a nice coating a dust, along with the main mirror and inside of the screen.
This is the guy right here. Looks to be under three years old according to the review dates.
Jay, you’re right - it has three guns. Wonder if it’s power supply - hmm.
[quote]Quote:
Originally Posted by nwgirl123
Update - I just spoke with a repair guy and he said my picture tube was blown and that I would have to replace all three (not just the one blown) for $479 per tube! WTH?? Does this sound right to anyone out there? (Doesn’t include his labor costs.)
Did they take your Tv to thier shop? THE most important thing when choosing a servicer and/or policy is get one that does in-home repair.
The red tube not working can be bad tube, bad IC on the crt pcb, or no red drive from the signal board/jungle chip. If they found a bad crt, they can certainly replace just one, but if the other two are aged/fading then they will never get the grayscale to set up correctly. A two year old set should not need all three replaced.
Hammer[/quote]
The biggest problem with the CRT-gun based rear-projections is that replacing the guns out-of-warranty is usually not worth the cost.
Sony had to come replace all three of my guns under a warranty/recall. The service guy said it was $1000 in parts alone for the three guns + the 2.5 hours he was at my house replacing them and re-doing the convergence.
If it needs more than just taking it apart and cleaning everything you’re probably much better off putting your money into a new set.
That being said, these three gun projection sets sure seem to hold up well. Mine is 6+ years old and is on 5pm to 11 or so most nights. I took about an hour this weekend and redid the 64 point convergence and it still looks amazing. I was just looking at my neighbors new plasma and can honestly say mine looks just as good. It can’t upconvert nearly as well as a new set though.
Here’s one reply I got from an electronics site:
By premtech
Rank: Guru
Rating: 88%, 377 votesThe procedure for correcting dark picture is EXTREMELY dangerous… If you’re not sure about what you’re doing call a qualified technician or you could seriously hurt yourself or get killed!
Picture Dark, abnormal, Changing Color Temperature
Clean the Spark Gaps on each CRT PWB. Remove the Cap, clean the contacts with thin fine sand paper, blow out, reseal.
Remove the CRT Sockets, clean the pins on the CRT. Push the CRT socket on and off several times.
Make really sure before you sttart this process that the Tv has been unplugged for several hours and that you discharge the crt as you remove the anode. There is some extremely high voltage present for hours after the Tv has been off…
Or get a reputable shop to come out and do the procedure for you - - might just save picking yourself up of the opposite wall.
Bill
Alright, potentially lethal doses of power! TV’s been unplugged for about 5 days now, I just worry bout those caps holding the juice in.
Does make sense though, if the gap’s not clean you’ll get lower lumen output.
IB4 your hair catches on fire.
i had to replace parts on a JVC projection TV.
I HATED IT.
replacing the IC’s and resistors was cake, but fixing the
totally screwed convergence took me 2 hours.
when I started it was bowed like you were in some theater with a curved screen.
on the JVC, there was an adjustment for the intensity of each tube.
try to find service manuals if you can.
[quote=“TrueBlue,post:6,topic:40147"”]
Here’s one reply I got from an electronics site:
Alright, potentially lethal doses of power! TV’s been unplugged for about 5 days now, I just worry bout those caps holding the juice in.
Does make sense though, if the gap’s not clean you’ll get lower lumen output.
[/quote]
it makes sence. additional electrical resistance means less power for the desired connection.
not sure what the “gap” is though… i dont fix TVs 
More goodies. I am really getting more and more excited to work on this thing. Almost as fun as engine teardowns. 
You have a very nice unit there, capable of greatness. PLEASE treat it right!
I don’t believe any of that written above is necessary. I believe it is massive overkill, just like cleaning the internal multiple lenses inside your lens stacks. Doable, all of it, but definitely not necessary. I have remedied dim pictures on countless CRT RPTVs, always totally effectively, and have never once done anything described above.
Tho once on a VERY old set I bridged the low impedance buffer resistor for the filaments, which also worked extremely well. But that was on VERY old tech, and won’t apply to current tech.
And you NEVER remove the anode cap on a triple-gun CRT, or where its other end plugs in, unless wanting to remove/replace the corresponding tube! Or the flyback or its HV distributor. Playing with the anode cap is TOTALLY out of bounds for the normal consumer. Stay away.
The optics are probably filthy, as is the case with any triple-gun CRT set over 3 years old. Get them professionally cleaned. And that does NOT mean by some minimum wage guy sent out on an extended warranty, even a licensed and seasoned and reasonably well paid repair tech. Optics on these babies are irreplaceable, and scratches are permanent. As are scuffs as well, which are simply thousands of tiny scratches at a time.
This will probably need to include the deeper optics.
Sub brightness can be escalated in the service menu, for balancing the dark areas and recalibrating center on your br user control, as can subcontrast as well. This is usually sufficient, in my calibrations.
If all else fails, the Screen controls might need to be goosed up a bit and rebalanced, which of course will then entail a complete ISF calibration. Which can only happen after the rebalancing of the Screen controls, and ISF doesn’t teach how to do that. You need someone who already knows that part.
I am available for phone consultation, if you want to do it yourself. Otherwise have someone on it who ALREADY knows what they are doing.
Mr Bob
throw this POS in the dumpster before somebody gets hurt.
Hey, I think I suggested just taking it apart and cleaning it long before that guy. 
Just ignore me though, I’ve only had mine for over 6 years. 
FYI, you HAVE to rpelace all 3 guns anytime there is an issue with them…
the 2 remaining guns have lost some of their brightness, if you just replace the green gun, the greens will be out of spec and you will have a green hue on your TV…
this can be compensated for a lil bit on the tV< but not if the tv is old…
repairing/replacing CRT tubes is a giant PITA and you can really shock yourself… good luck
Get it cleaned, and don’t play around with the tubes unless you are familiar with proper discharging procedures and have worked on CRT tubes before especially the anode cap advice, that just screams bad news there especially if it’s not fully discharged.
That last quote posted is the probably best advice to take. There is a reason why these have those warning labels everywhere. And more than likely it’s a simple fix.
So - I fixed it!
Awesome screen response - what you’d expect from individual CRTs firing at a polished mirror. No playing around with electrodes was needed - just a solid 5-hour cleaning/degaussing/reaiming convergence session. ran it against my cal’d HD tube Triniton Wega for accuracy. Not bad. Need my Avia back for calibration, but damn, pretty happy so far.
Jay, I rarely doubt ya anyway. It’s the quality of the cleaning that will get the job done - that and the fact that you can individually select each gun as needed for aiming that made a huge difference here. So you get a +1.
Offered the guy his set back three times this weekend and he declined politely and gracefully. Think I found a good sportsbar set. Thanks all.
:tup:
I really should tear mine apart and clean it. Been at least 2 years since I had the case apart. After we had new carpet put in last year I noticed the house was especially dusty for a couple months so I’m sure the mirror and lenses are coated.
I ran into a few good sites for cleaning tips and tactics, if you want them. I used the Lens Crafter wipes and spray (won’t hurt antiglare coatings, so it’s safe for the lenses) and a microfiber. The lenses have a digital convergence calibrtion program that I ran after.
Post those up if you would. I probably won’t have time until after Christmas but I’d like to start reading and getting any stuff I might need to pick up.
Plus, after re-doing the convergence my TV looks really good again. I don’t want to risk taking it apart before the party we’re having for the ice bowl. People have been promised 51" of HD Ice Bowl glory so I have to deliver on that one. 
I have the same TV. :tup:
Can you post or PM me those websites?