View Single Post
  #73  
Old 04-19-2019, 10:17 PM
Yamamaya42's Avatar
Yamamaya42 Yamamaya42 is offline
VideoKarma Member
 
Join Date: Nov 2018
Location: Round Rock TX
Posts: 3,177
Quote:
Originally Posted by Electronic M View Post
Dynamic convergence tip: if the board is fine but it is pretty far off at all pot settings try moving the convergence yoke as much as 1/4" forward or rearward of it's designed position (over the end flare of the electron gun/or red dag ring if the gun is hidden). Sometimes The dynamic field overall is too strong or too weak and moving it fore/aft can act as a mechanical gain control. If the outer 1-2" radius is kinda lousy but looks decent from 15-20' viewing distance you may have optimized it. Perfect convergence to the edges on a roundy is a rare achievement.

Some focus ideas: there should be a ~3-6KV ceramic cap on the focus coil that may not be holding correct capacitance value. IIRC the 16 is tube focus rectification...I tend to switch most focus rects to modern SS HV diodes. Removing the filament load relieves the flyback, and tube focus rects are not always as stable as I like.

If you can get the HV cage open to look for arcing/corona that may help.
They did once make solid state sub for the HV rec (NTE508) if you could find one, would using one also lessen the load on the FB? ans what would one replace the focus rect (2AV2) with?

Last edited by Yamamaya42; 04-19-2019 at 10:21 PM.
Reply With Quote