RCA PFR100 Projection set

rcaman do you know what the R11** knobs do on the convergence board? How is the quality on the 2 sets that you still own? What kind of quality can I expect with the right tweaking?

OK, I took the lenses off and am going to give them a good cleaning, can I clean the glass on the crts, and if so what should I use. Anyways I can see the raster which is slightly brown, almost rectangular in shape, the blue crt seems to have the lightest brown area, is this area the burn? other than the brown I don't see anything that looks like a burn within that area.

Ok the blue crt is a 4 and the other 2 are a 5 on this webpage http://home.centurytel.net/rshannon/AVS/crtburn.htm, so it looks like I will probably be wanting to replace them sooner than later.

[rcaman]

i always cleaned them with windex. they do play better with clean lenses and crt faces.

[rcaman]

hi, i would have to locate my schematic. the 2 sets i have were heavy used, to me they dont have a good picture. but i am used to watching a 61" hdtv now. in terms of the technology of that ere i guess they still do pretty good. havent turned them on in a long time. they were a sight to see when new. steve

[rcaman]

by the way i never had to replace a crt in those sets. hitachi didnt run their tubes a hot as the competition did. i used to have an ad that touted hitachi projection sets will last 7 times longer than the mitsubishi sets. mga ran their tubes almost to the max. in 87 i was hitachi,s biggest projection dealer in the memphis tn. distribution area.

I've heard a couple of people say that these sets last forever, reasuring to hear it from someone who sold them. They are built like a tank. How easy is it to change a crt, I have a basic understanding of electronics and have heard that crts can hold a charge for a very long time and am afraid of getting electrocuted. Any chance I could get you to scan your schematic if you can find it? Thanx for all your help

I have one last thing to ask, I am having a slight problem getting the convergence right, would it be possible for someone who owns one of these tvs to take a picture of the convergence board so I can see the proper position of the convergence pots. It is located under the top panel on the left hand side.

[andy]

The positions of the convergence pots will vary from set to set, so a picture of another set won't help. They have to be adjusted for the exact CRTs, yokes, lenses and mirror position in your set. You have to adjust things in the correct order because the control interact. If you've never done it before, it would be a good idea to find the convergence instructions of a projection TV. They are all pretty similar once you know what to do.

The basic steps are:

1. Turn off the red and blue and adjust the green for good size and geometry.
2. Turn on the red, or blue and adjust along the center line for a well converged 'plus' sign across the screen.
3. Put up a full cross hatch and adjust for corect size and linearity along the center lines.
4. Adjust for best convergence in the corners.
5. Repeat steps 2-4 until it's as close as it can get.
6. Repeat 2-5 for the remaining color.

If you replace a CRT you will also have to adjust the centering and rotation on the deflection yoke.

It's not that bad, but you need something to tell you what all the controls do. You can't get good results by randomly tweeking to pots.

I have the avia home theatre dvd with the convergence test patterns, but as you say I am not sure what the pots do exactly, would these be the same for most projection tv's.
here are the pots:

H-SIZE H-LIN V-BOW H-BOW V-LIN V-SIZE H-SKEW H-KS V-KS
R1191 R1182 R1183 R1158 R1157 R1136 R1137 R1141 R1121

* * * * * * * * *

R1190 R1180 R1181 R1160 R1159 R1138 R1139 R1255 R1120

* * * * * * * * *

[andy]

The functions of those pots are pretty much the same on all projection TVs. I don't have time right now to describe all of them, but I will post back later.

[kc8adu]

you need a plumb bob and level
the level lets you stretch a string exactly level across the center of the screen.
the bob does the same vertically.
use these as a reference when setting the green geometry as perfectly as possible.
once you get the green perfect you adjust the red nd blue to it.
think of the controls as size,width center,lin ect.forget what you know about old delta gun work for now.
cover red or blue and work on getting it one with the green.
repeat for the other.
take your time and it should come out near perfect.

using string is a great idea, I was thinking that I would have to use tape, but I like the string idea. I noticed when messing with the pots that the green moved on its own, and the blue and red moved with the same pots, is this normal? It sounds about right from what you guys are saying. Anyways thanx a lot for the help its really appreciated.

OK, so i've measured the screen and attached a string cross hatch to it, i'm using the convergence test patterns on the avia dvd and I am noticing a couple of things, first this tv has a curved screen tilted forward so I am not sure how to take the keystoning into account when I measure the screen, up close the 4 sections look even, but from a distance they don't look right. The second is when I adjust the convergence I can get it right on one side but the other side is off. I ve figured out that the top row of 9 pots is for the red and blue, while the bottom row of 9 is for the green. There are 3 more pots inside the tv under the green crt, they are very hard to get at, and I no longer feel very comftorble sticking my hand in there with the tv on since I got shocked adjusting the drive on the blue crt.

[rcaman]

i forgot to tell you. there is a slide switch on the convergence alignment board. flip it and you have a full crosshatch screen when you push the align button on the front panel. my 2 sets does not have great convergence. but i have seen some that had great convergence. good luck steve