View Single Post
  #6  
Old 11-12-2021, 09:06 PM
Yamamaya42's Avatar
Yamamaya42 Yamamaya42 is offline
VideoKarma Member
 
Join Date: Nov 2018
Location: Round Rock TX
Posts: 3,176
Quote:
Originally Posted by Electronic M View Post
I think what Yamamaya42 is getting at is that despite the monitor generating it's own horizontal and raster, the video stage is designed to bias off all gun emissions until there is a video signal.

Some projection televisions have similar circuits to prevent screen burn if deflection fails.
Correct, by design, w/o any input from the card, all flow of electrons to the screen are cut off.
this is so they can get as sharp as a display of the letters as they can, this is NOT like any analog display. but under TTL input control.
https://tunneler.org/files/IBM-Techn...2-Hardware.pdf

that shielded link you are seeing is NOT and RF cable, but most likely a shielded path for the TTL coding to the amp on the CRT pcb.

the early IBM mono cards were VERY limited in what they could display, having on/ off reverse or underline or combo there of, that was until The Hercules Graphics Card (HGC) and changed everything.

They found a way to cheat and show graphics on a monochrome monitor.
__________________
=^-^=
Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte.
いとおしい人のために
Reply With Quote