CurtPalme.com Home Theater Forum

[jmcmahon7]

Hi Folks, I just acquired a Runco 750 and the quaility made me research CRT's more. I have to say I'm impressed, cars looked amazing on it! We'll be using this one for movies outside during the summer (when I finally get it setup/calibrated for 10ft screen). But Im also pretty sure ill be getting a CRT for the Home theater too, just the ability to "read" the life of the tubes is a big plus.

So, I have a question on the Runco 750....Ive downloaded the manual, however I do have one question.......can anyone tell me how to adjust the raster (I think thats what its referred to) on this unit. I cant find anything in the manual about raster. By raster I mean position the picture on the tube(s) centrally/optimally so that its not bleeding over the edges of the tube. Im sure its probably in there I'm may not be reading it properly.

TIA! This site is an awesome resource....ill be sure to have a look over at the HTPC forum and see if I can contribute too.

[macgyver655]

Mechanical raster centering for each individual tube is on page 26 in the manual. There is also an electronic centering in the service menu ( see pages 20 and 21 ) and this affects all 3 tube at the same time. It is a master centering.

[jmcmahon7]

Thanks for the speedy reply. I'll re-read those pages. I assume I should start with the "individual" ratsers first? Do they all three need to be in the same position within the tube?

I Here's what I was thinking of doing, let me know your thoughts.....

1 Remove the lenses
2 Check the wear on the tubes
3 adjust the raster on the tubes
4 Setup the toe for the size screen I want (10ft)
5 do the whole convergence "thing"
6 Drink beer and watch movies, play Super Mario 3 on the NES.

Any potiential pitfalls that come to mind? I noticed a lot of the adjustments are done at or near the tube while the unit is powered on, I assume I need to be careful just like with any other CRT?

[AnalogRocks]

[AnalogRocks]

[Curt Palme]

Hah, I think you emailed me through eBay this afternoon, I just emailed you back all of the links... and here you already are..

Forget about raster centering, that's more or less already done in the Zenith.

Do check for wear and fungus, DO NOT pull off more than the 4 screws for each lens, otherwise you'll dump out a pint of cooling fluid if you take the metal ring under the lens off.

You'll need an external test pattern like the AVIA disc to generate the crosshatch needed for convergence. Try and do it with some moving source, and you'll drive yourself nuts with it.

As I said in the email, I have all the parts you ever need for this set, tubes are $200 each from VDC if they're badly burnt. You'd need to change all three if they are, as the Zenith has an auto color tracking circuit in it, and dropping in one new with two used tubes will get you a really green screen, since the tube emission of the green tube (the most worn one) is way higher than the older tubes.

I spent 2 days trying to overcome that 'feature', and you can't do it. (at least I can't!).

have fun with it, it's a good set!

[Curt Palme]

Hah, I think you emailed me through eBay this afternoon, I just emailed you back all of the links... and here you already are..

Forget about raster centering, that's more or less already done in the Zenith.

Do check for wear and fungus, DO NOT pull off more than the 4 screws for each lens, otherwise you'll dump out a pint of cooling fluid if you take the metal ring under the lens off.

You'll need an external test pattern like the AVIA disc to generate the crosshatch needed for convergence. Try and do it with some moving source, and you'll drive yourself nuts with it.

As I said in the email, I have all the parts you ever need for this set, tubes are $200 each from VDC if they're badly burnt. You'd need to change all three if they are, as the Zenith has an auto color tracking circuit in it, and dropping in one new with two used tubes will get you a really green screen, since the tube emission of the green tube (the most worn one) is way higher than the older tubes.

I spent 2 days trying to overcome that 'feature', and you can't do it. (at least I can't!).

have fun with it, it's a good set!

[Tom.W]

Also read this...

http://www.moesrealm.com/hometheater/crt-focus-guide.html

[macgyver655]

Hey Tom. I think I'm going to start calling you the linkmaster !!!!!!

[AnalogRocks]

[AnalogRocks]

[jmcmahon7]

[AnalogRocks]

[AnalogRocks]

[jmcmahon7]

[AnalogRocks]

[AnalogRocks]