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  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 140
Default Hitachi DP 27 chassis

Now this is really driving me nuts, and the first thing tomorrow it
gets stowed and we can make some money maybe.

OK, set comes in, shuts down immediately, with scope I find offset in
the convergence output, a pretty healthy one.

I pulled all that out of circuit, even the module.

Now I am troubleshooting the shutdown, it has everything, I know the
current shutting down the HV is from RN10. I have persued that, but no
matter what I disable, there is still votage at the cathode of DN09 (I
think, but that's the one that clamps the pulses to the trigger input
of the HVOT driver IC an M625 something).

Intermittently the SMPS on the right (from the back of set) cycles
intemittently. I assure you the STKs are gone, I literally took them
out.

Now when this is happeneing, the SMPS cycles on and off, and the light
for the -28 stays lit well after you unplug it, but then the
convergence ICs have been removed. Now, the light next to it must be
for the +28, it would seem logical. That one drops like a rock when
the SMPS shuts down.

What else runs off the +28 ? Also there is the smell of heat, but I
have let it run until it happened and then just about touched every
component on the chassis. The CRT sockets are already unplugged.

This thing is running me around here, I think it would be useful to
know what else runs off that +28, I have all kinds of things unplugged
left and right, and even though I can smell the heat, I can't seem to
find it. I have run my finger around that chassis and the warmest
thing is the jungle IC, and it ain't hot, just warm. It probably runs
off the other part of the power supply anyway.

So what all else does the +28 feed in that thing ?

Any help appreciated, it is late, I must go.

Be well.

JURB

  #2   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 140
Default Hitachi DP 27 chassis

Oops, I think that is DP24 chassis, not 27.

Sorry.

JURB

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
Hitachi AP62 Chassis Flyback Needed Shoreline Electronics Electronics Repair 3 January 28th 06 04:26 PM
HITACHI 37U59B CHASSIS M9LXU gudule Electronics Repair 1 September 21st 05 11:24 PM
19" Hitachi tv model:CT2033B,chassis:FH89XS-2 Sidney Electronics Repair 3 September 27th 04 12:52 AM
27" Hitachi tv model:TN-77032,chassis:G9LXU Sidney Electronics Repair 0 September 2nd 04 03:30 AM
27" Hitachi tv model:TN-77000,chassis:G9LXU Sidney Electronics Repair 2 September 29th 03 05:35 AM


All times are GMT +1. The time now is 02:04 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"