Television question... - diyAudio
Go Back   Home > Forums > General Interest > Everything Else

Everything Else Anything related to audio / video / electronics etc) BUT remember- we have many new forums where your thread may now fit! .... Parts, Equipment & Tools, Construction Tips, Software Tools......

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 23rd October 2012, 05:18 PM   #1
toptip is offline toptip  Turkey
diyAudio Member
 
Join Date: Dec 2004
Location: Istanbul
Default Television question...

I know this is the "audio" forum but I have to start somewhere and our members have such varied interests. So here goes...

One of my interests is renovating old B&W TVs, ones of some design interest. That represents a relatively small world: as someone said, "As soon as TV was invented it became a high-tech commodity" -- there was tremendous competition for technological improvement combined with downward pressure on price, so design was largely ignored. Nevertheless there are maybe some 50-100 interesting TVs.

So, I restore these TVs cosmetically and often also the electronics. But sometimes I do not want to, the electronics that is. It is painful -- you have to replace may be a hundred capacitors in tight spaces AND it is dangerous, you are dealing with 600 to 25K volts!

So my question: are / were there any "generic" TV chassis made that can power any CRT -- ones that can be adjusted for coil impedances, voltages, etc.

This would sate my craving to see the TV running without orphaning my kids!

I would appreciate any suggestions.
  Reply With Quote
Old 23rd October 2012, 05:33 PM   #2
Pano is offline Pano  United States
diyAudio Moderator
 
Pano's Avatar
 
Join Date: Oct 2004
Location: Kona, Hawaii
Blog Entries: 4
Not for Black and White that I've found. I searched and searched for something for my old Predicta TV with no luck.

I hope someone here can prove me wrong!
  Reply With Quote
Old 23rd October 2012, 05:47 PM   #3
diyAudio Member
 
jackinnj's Avatar
 
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
There were generic chassis re-branded for some department stores, or you could purchase one in a plain black steel cabinet. (That's the one which shocked me so badly I was thrown across the room.)

I used to take them apart for the tubes, power supply caps and power transformers. Still have the Weller Gun which could unsolder an electrolytic from the chassis.

My first ham transmitter used a 6DQ6 and trafo from a discarded TV.
  Reply With Quote
Old 23rd October 2012, 06:40 PM   #4
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Some chassis designs were re-used with different external styling but there is no such thing as a generic design. They were all similar, but all different.
  Reply With Quote
Old 23rd October 2012, 06:51 PM   #5
diyAudio Member
 
Osvaldo de Banfield's Avatar
 
Join Date: Dec 2011
Location: Barrio Garay,Almirante Brown, Buenos Aires, Argentina
It is almost impossible, the horizontal deflection stage is tuned, and the yoke coil is the most important part in this tuned circuit, so replacing one yoke by other may cause severely malfuction in the receiver, including red plate in the HO tube, and or power supply damages.
__________________
LW1DSE
  Reply With Quote
Old 23rd October 2012, 07:38 PM   #6
toptip is offline toptip  Turkey
diyAudio Member
 
Join Date: Dec 2004
Location: Istanbul
Quote:
Originally Posted by Osvaldo de Banfield View Post
It is almost impossible, the horizontal deflection stage is tuned, and the yoke coil is the most important part in this tuned circuit, so replacing one yoke by other may cause severely malfuction in the receiver, including red plate in the HO tube, and or power supply damages.
This is true -- is it not called "flyback?" Also there is some distorting of the waveform towards the edges and corners of the picture tube to correct for distortions introduced by the angle of the ray.

But, as a slight non-sequitor, I have recently learned that all stereo FM transmission today is done by DSP, meaning, I assume, the waveform that is finally applied to the transmitter is produced by digital manipulation rather than -- oh so complicated -- analog means.

I presume this is possible for TVs too and the most recent CRT TVs before their demise (especially those with completely flat screens) must have used some sort of DSP to generate the sawtooth patterns rather than relying on analog tuning and resonance networks.
  Reply With Quote
Old 23rd October 2012, 07:50 PM   #7
diyAudio Member
 
Osvaldo de Banfield's Avatar
 
Join Date: Dec 2011
Location: Barrio Garay,Almirante Brown, Buenos Aires, Argentina
No, yoke and Fly Back transformer (It defines its function, no its name), are both parts of the horizontal output stage, but are inter-depending between them. In fact, all capacitances in the circuit (including parasitic ones) and all the inductances (HOT, yoke, width and linearity coils if they exist) are all part of a 5th harmonic tuning in the entirely output stage.
__________________
LW1DSE
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Those Magnificent Television Tubes JohanB Tubes / Valves 371 8th December 2014 12:02 PM
Surround sound amp, Sub woofer and television warrennyc Subwoofers 4 3rd January 2005 11:33 AM
distance from television ALFIrE Multi-Way 2 30th March 2004 07:46 AM
Television broken Bull Everything Else 3 21st January 2003 01:08 AM


New To Site? Need Help?

All times are GMT. The time now is 12:19 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2