Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Early Television Foundation CRT Rebuilding Project

We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #1  
Old 10-26-2014, 01:24 PM
N2IXK's Avatar
N2IXK N2IXK is offline
Technohippie
 
Join Date: Apr 2011
Location: Sittin' on the "Group W" bench...
Posts: 801
Unfortunately, just robbing the gun from a 7JP1 scope tube won't work.

Once the tube is let down to air, the cathode needs to be replaced, because the active oxides become contaminated. If you are going to go through all that trouble, you might as well just rebuild the 7JP4 guns themselves...
Reply With Quote
  #2  
Old 10-27-2014, 03:33 PM
Electronic M's Avatar
Electronic M Electronic M is offline
M is for Memory
 
Join Date: Jan 2011
Location: Pewaukee/Delafield Wi
Posts: 14,820
Quote:
Originally Posted by N2IXK View Post
Unfortunately, just robbing the gun from a 7JP1 scope tube won't work.

Once the tube is let down to air, the cathode needs to be replaced, because the active oxides become contaminated. If you are going to go through all that trouble, you might as well just rebuild the 7JP4 guns themselves...
I was NOT trying to say that if the cathode is dead in a 7JP4 to just swap the gun from a 7JP1. I understand that the cathode would need to be rebuilt. Someone earlier insinuated that the guns on 7JP4s were very fragile and may be damaged in shipping despite the rest of the CRT being fine, and I was responding to that by saying that if the gun is damaged beyond rebuild-ability one that could be rebuilt and installed might be obtained from a scope CRT....That and one could potentially make new 7JP4s by rebuilding a 7JP1 and rephosphoring it with P4 phosphor.
__________________
Tom C.

Zenith: The quality stays in EVEN after the name falls off!
What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
Reply With Quote
  #3  
Old 10-27-2014, 08:19 PM
WISCOJIM WISCOJIM is offline
VideoKarma Member
 
Join Date: Sep 2005
Location: Grand Chute, Wisconsin
Posts: 2,456
I'm hoping someday they can make a bunch of 3KP4s out of all the 3KP1s I've been saving.

.
Reply With Quote
  #4  
Old 10-27-2014, 09:51 PM
Electronic M's Avatar
Electronic M Electronic M is offline
M is for Memory
 
Join Date: Jan 2011
Location: Pewaukee/Delafield Wi
Posts: 14,820
Quote:
Originally Posted by WISCOJIM View Post
I'm hoping someday they can make a bunch of 3KP4s out of all the 3KP1s I've been saving.

.
That has the potential of being even more lucrative than doing the same with the 7" CRTs. There would be a lot of happy Pilot TV owners...
__________________
Tom C.

Zenith: The quality stays in EVEN after the name falls off!
What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
Reply With Quote
Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 01:43 AM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.