AVS Forum banner
Status
Not open for further replies.
1 - 11 of 11 Posts

·
Registered
Joined
·
8,359 Posts
Thanks, but I've already been in touch with a person who makes these for sale over the net. He himself has suggested first trying to change things in the service menu. The red push thingy was built for the 25% push of the Mitsubishi, and according to Avia, my push was a bit less than that at around 20%. Furthermore, it doesn't correct the problem for TV broadcasts, just for component video (ie. my DVD). The Radio Shack one is an option (and cheap) but I've been told that it can introduce some undesirable artifacts.


Anyways, I've set a couple of things differently according to some specs I've found on the net and it's helped a bit, but it hasn't solved my problem. (I've not remeasured the push yet.) I'm not sure exactly what settings to change to fully address the problem. Changing the RCUT field didn't help. Colour intensity changed, but the push was still there.
 

·
Registered
Joined
·
8,359 Posts
My TV is a cw34xc2 but I'd appreciate sites on any of the widescreen Toshibas.
 

·
Registered
Joined
·
8,359 Posts
In the service menu I mean.
 

·
AVS Forum Special Member
Joined
·
11,139 Posts
Discussion Starter · #7 ·
Haven't put as much effort into fixing a moderate red push problem with my Philips 64PH9905 as Mitsubishi owners have, BuGsArEtAsTy. Just as my warranty expired in June I had two non-Philips service techs (different companies) in to look at it. Neither wanted to tackle it. (The dozen-odd Philips-authorized servicers I called wouldn't even visit, or return calls.)


I can adjust color/tint for seemingly normal flesh tones, but a large red object such as a jacket is clearly too red; also, strong blues have too much Navy hue (presence of red), and magentas or purples are often 'off'. So far I haven't seen comments from other 64PH9905 owners with a similar problem.


Since my set has a built-in NTSC and HDTV tuners, and most of my viewing is OTA, a resistor network at the red component-in jack won't help me. I concluded the only potential fix was to increase the value of the equivalent internal resistor--believe it's the red-matrix output on my color-amp board, but haven't studied the schematic that closely yet. My approach would be to parallel that resistor with a higher-value potentiometer, tweak the pot until the Avia red-push test was okay, then tack on a fixed resistor at the pot's value (to avoid possible board damage with unsoldering). One of these days. Meantime, like you, I'm looking for alternatives. -- John


[This message has been edited by John Mason (edited 08-07-2001).]
 

·
Registered
Joined
·
8,359 Posts
Quote:
Haven't put as much effort into fixing a moderate red push problem with my Philips 64PH9905 as Mitsubishi owners have, BuGsArEtAsTy. Just as my warranty expired in June I had two non-Philips service techs (different companies) in to look at it. Neither wanted to tackle it. I can adjust color/tint for seemingly normal flesh tones, but a large red object such as a jacket is clearly too red; also, strong blues have too much Navy hue (presence of red), and magentas or purples are often 'off'. So far I haven't seen comments from other 64PH9905 owners with a similar problem.


Since my set has a built-in NTSC and HDTV tuners, and most of my viewing is OTA, a resistor network at the red component-in jack won't help me. I concluded the only potential fix was to increase the value of the equivalent internal resistor--believe it's the red-matrix output on my color-amp board, but haven't studied the schematic that closely yet. My approach would be to parallel that resistor with a higher-value potentiometer, tweak the pot until the Avia red-push test was okay, then tack on a fixed resistor at the pot's value (to avoid possible board damage with unsoldering). One of these days. Meantime, like you, I'm looking for alternatives.
I've been told by a few people now that for the Toshiba's much of the red push problem can be corrected solely from the service menu, and my friends with Toshiba RPTVs say their red is bang on. Indeed, the menu seems extremely flexible... I've already been able to correct some of my pixel cropping problem, at least vertically. However, I have not been able to fix my horizontal pixel cropping nor my red push. There are a bazillion settings, and I don't know what most of the mean, even with the guides out there. I won't hazard to soldering - I have zero experience in this sort of thing.


As for greyscale, I shall wait for my Video Essentials to arrive, since I've been told it's not correct using Avia. Eyeballing with VE is said to be much better than eyeballing with Avia.
 

·
AVS Forum Special Member
Joined
·
11,139 Posts
Discussion Starter · #9 ·
I've seen service-menu fixes for red push in Sonys at one of the links I provided above, but not for Toshibas. Other than a few skilled do-it-yourselfers, I get the impression lots of folks tinkering with service tweaks just mess things up. There's still misunderstanding about gray scale vs. red push. See Chuck Williams' reply in this short thread . Also, see Guy Kuo's (Avia's designer) writeup here . If you turn your color off, and/or view several b&w movies, and you don't see any color hues in dim and bright image areas, you shouldn't touch gray scale adjustments. -- John
 

·
Registered
Joined
·
8,359 Posts
Well, I have no idea what my colour temp truly is, and I have not attempted to really change my greyscale either. It looks fine with black and white movies anyway. (Strangely enough, my TV has a B&W setting... it certainly solves all my red push problems. http://www.avsforum.com/ubb/wink.gif It also has a negative and sepia setting. http://www.avsforum.com/ubb/confused.gif Whatever for I have no idea.)


Anyways, it looks like for right now I'm not going to get too far. I've been told that for the Toshiba one must set about 5 different variables to correct the red push (while keeping greyscale OK). Since I don't know which variables to change, I'm out of luck. I can only change 1 or 2 variables at a time in my trial an error method, which obviously hasn't helped. So for the time being, I've settled for partially correcting minor issues. http://www.avsforum.com/ubb/frown.gif
 

·
AVS Forum Special Member
Joined
·
11,139 Posts
Discussion Starter · #11 ·
Quote:
Originally posted by BuGsArEtAsTy:
Since I don't know which variables to change, I'm out of luck.
You might try posting at both hometheaterforum and ***************. If there really is a reliable menu sequence, you'd think all the menu tinkerers would know. (BTW, I got the supposed 8500 temp for my set both from its designer and an early ISF-type review. I theorized a 'bluer' temp might be causing some of my blue-hue problems, but believe now it's linked to red push.) -- John

 
1 - 11 of 11 Posts
Status
Not open for further replies.
Top