Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Redbone
 
Posts: n/a
Default Quasar Projection TV and AN5521 Vertical Problems

I have a Quasar Projection TV with a very unusal vertical problem.
This unit uses an AN5521 vertical IC. I have checked ALL of the
electrolytic capacitors for value and ESR all check o kay. The vertical
problem I have is that this unit will have full raster and no vertical
foldover....after 20 minutes this unit will still have a picture or
raster but with a faint line which is horizontal. Someone told me that
this may be caused by oscillation of the vertical IC ( AN5521 ). I was
also told that this could be fixed by putting a 560 PF capacitor on
pins 2 & 5 of the vertical IC and if this did not work the try a 1, 000
PF capacitor. I am confused because this was to fix only vertical
instability. And the chassis that were affected bu this problem a
AMEDP 807, YAMEDP 807, AEDP 807, and YALEDP 807.

Since Matsu****a made this chassis, the Panasonic models affected
by this problem a

PTP - 4586, PTP - 4588 , PTP - 5189.

The measurements on the pins of the AN5521 read as follows:
Pin # 1................ Ground
Pin # 2............... Output 16.5 v DC and about 54 v Peak to Peak
Vertical output
Pin # 3.............. Boost about 29.8 v DC.
Pin # 4.............. Input 0.7 v DC and about 0.8 v Peak to Peak
input.
Pin # 5.............. Feed Back Pin reads about (-) minus 0.2 volts
Pin # 6.............. Amp pin .... 2.56 v DC
Pin # 7............. Vcc about 28 volts DC

This unit has no convergence problems noted with a cross hatch
patteren. Could this be in the Jungle IC or Processor IC. Or else
where? Any ideas will be greatly appriciated.

Pat Green
Cowboy's Appliances
Beaumont, Texas



Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Zienth Vertical Squish (How do I find and test the Capacitor?) Kevin Cornwell Electronics Repair 8 September 15th 03 03:17 PM


All times are GMT +1. The time now is 12:12 PM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"