CurtPalme.com Home Theater Forum

GREG1292 · Joined: 10 Oct 2006 Posts: 417 Location: indiana

Am I better off going with VDC rebuilt tube or holding out
for good conditioned used blue tube. Also if I get the tube
from VDC do I need to use John Wittmans guide and drain the
glycol.

Also are there some short throw lens that will fit a G70?

Thanks

gjaky · Joined: 05 Jun 2010 Posts: 2802 Location: Budapest, Hungary

Blue tubes are usually lasts longer than the greens so I would think there are many bare blue tubes out on the used market if you look for a cheap solution, an original VDC tube probably costs 10x more than a good used one.

For short throw there is only one solution, get HD117-24 lenses from barco retro sets, but I'm affraid in this case you'd have to change the C-elements as well, and barco C-elements are all clear.

GREG1292 · Joined: 10 Oct 2006 Posts: 417 Location: indiana

GREG1292 · Joined: 10 Oct 2006 Posts: 417 Location: indiana

Maybe this is a dumb question but I will ask anyway.

Can a red tube be stripped down and converted to a green tube? By swapping the colored elements and if so
just use the tube swap guide on the forum?

ecrabb · Posted: Fri Sep 28, 2012 3:01 pm Post subject:

No, you can't do that, Greg... The phosphor on the tube face (when the electron beams strikes it) is where the spectral emission comes from; it's the particular makeup of the phosphor which determines the color. Each tube has an inherent color, regardless of whether it has color-fitering glycol (in AC) or a color-filtering C-element (in LC).

Bottom line is, red is red, and always will be red.

SC

gjaky · Joined: 05 Jun 2010 Posts: 2802 Location: Budapest, Hungary

No, you can't do that. The colored C-element is only a fiter, but the color comes from the phosphor of the CRT. You might think they are similar by visual sight, but they reacts differently to electron ray that's why they emitt different colour.

GREG1292 · Joined: 10 Oct 2006 Posts: 417 Location: indiana

Thanks for the great replies. Nice to learn something new about an old technology.
I actually thought it was the pinout of the tube! Just received a minty blue and red tube
with no need of the red at this time hence the question.

CIR Engineering · Posted: Sat Sep 29, 2012 5:41 pm Post subject:

If you do a rebuild tube, you can have a red tube converted to green when the phosphor is changed. But you obviously can't do that yourself.

craigr

GREG1292 · Joined: 10 Oct 2006 Posts: 417 Location: indiana

Couple of quick shots from a cell phone on 128" curved screen 1920x800 silver fire 2.0 sony g 70[/img]