Return to Uncreativelabs.net front page Uncreative Labs
PC XT and AT forums
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

 IBM 8513 making screeching noise View next topic
View previous topic
Post new topicReply to topic
Author Message
386er



Joined: 27 Jan 2007
Posts: 274
Location: USA

PostPosted: Sun May 02, 2010 2:19 am Reply with quoteBack to top

well, i had my old ibm 8513 sitting around and decided to hook it to my newest computer with the dual monitor setup, i could get it to go 640x480 and 720x480 and it ran fine with xp for a week and a half, i played games and movies, the colors ingame seem richer and deeper and i was amazed, only thing besides low max screen res is that is blurry as heck and i have to fiddle with the contrast and brightness to read text, i read some were its caused by a bad flyback transformer, yesterday when using it, i heard a loud hi pitched screech noise, it was still workin, but i turned it off, let it sit for a min and turned it on again, it still worked but screeched like a mosquito. after a day i turned it on and it dosn't screech.
is this monitor gona die soon? i can live with the blur. but the screech is makin me paronoid, whats ur opinions?
View user's profileSend private messageSend e-mailMSN Messenger
T-R-A



Joined: 02 Oct 2004
Posts: 576
Location: Western NC

PostPosted: Sun May 02, 2010 4:21 am Reply with quoteBack to top

Screeching sounds almost always mean a flyback-transformer's getting ready to go. Best bet is to consider another monitor, and soon....
View user's profileSend private message
386er



Joined: 27 Jan 2007
Posts: 274
Location: USA

PostPosted: Sun May 02, 2010 5:50 pm Reply with quoteBack to top

awww, funny thing was that i saw an 8513 like monitor at the dump months ago, unfortunetly they dont allow salvaging there. i see lots of crts get dumped at my work that are good, just that they are off brands and dont seem worth the effort, i only brought home 2 monitors from there, an old gateway 2000 that dose 1280x1024 and a 1993 ibm monitor(dont know the model) that dose 1164x768 that is my main monitor for 2 years now.
mabey i could replace the flyback my self, what type would be compatible with it?
View user's profileSend private messageSend e-mailMSN Messenger
T-R-A



Joined: 02 Oct 2004
Posts: 576
Location: Western NC

PostPosted: Sun May 02, 2010 11:07 pm Reply with quoteBack to top

Quote:
mabey i could replace the flyback my self, what type would be compatible with it?


Bigger question---how familiar are you with working on the inside of a monitor or TV? It's not a job for the inexperienced, and you could wind up with a useless monitor or fatal shock anyway. I'd strongly dissuade you from attempting this...
View user's profileSend private message
386er



Joined: 27 Jan 2007
Posts: 274
Location: USA

PostPosted: Mon May 03, 2010 2:00 am Reply with quoteBack to top

mabey ur right, well, it seems the screechin stoped. i have done a little work on tv's before, all the tv's i ever gotten were garbage picked ones i fixed. i guess i'll leave it alone for now since it stopped, thx t-r-a
View user's profileSend private messageSend e-mailMSN Messenger
ryan



Joined: 19 Apr 2006
Posts: 261
Location: WisConSin

PostPosted: Tue May 04, 2010 12:17 am Reply with quoteBack to top

386er wrote:
mabey ur right, well, it seems the screechin stoped. i have done a little work on tv's before, all the tv's i ever gotten were garbage picked ones i fixed. i guess i'll leave it alone for now since it stopped, thx t-r-a


Ah the buzz of death, remember if you did tweaking inside the monitor (like the screen was dim so you upped the voltage) that can also cause buzzing because you are going outside the spec of the screen.

Anyway, I've fixed up what seems like 100's of screens, most with very very minor issues all off the Computer renaissance dumping area, thing is I had an unlimited source in the 90's so If it had something tough (like your flyback) I didn't bother just brought it back and got another.

Now something to remember, although not necessarilly hard, are you really patient enough to rewind hundreds of coils of wire to fix? Also unless you can find a spec they need to be the same guage, # and pattern as they come off.

That said I still use an 8513 as my main screen, but mine is crystal clear and has beautiful color, I wonder why old IBMs always make the picture nicer than newer screens.

Oh and 40kv does hurt, one hand rule always applies and a good ground fault ahead of the screen . Never did bite me (and I started around 14)

Good Luck
Ryan
View user's profileSend private messageVisit poster's website
386er



Joined: 27 Jan 2007
Posts: 274
Location: USA

PostPosted: Tue May 04, 2010 12:34 am Reply with quoteBack to top

my 8513 is TOO bright. think lowering the voltage will help it? never tweaked this one before. winding up flybacks by hand sounds like fun o_O , biggest thing i ever wound up was an AM radio antene. dont realy wana junk this as i only got 3 monitors in the whole house.
View user's profileSend private messageSend e-mailMSN Messenger
ryan



Joined: 19 Apr 2006
Posts: 261
Location: WisConSin

PostPosted: Sun May 09, 2010 4:57 pm Reply with quoteBack to top

386er wrote:
my 8513 is TOO bright. think lowering the voltage will help it? never tweaked this one before.


I assume it would help, all you do is adjust the one of the dials on the big black HV voltage supply inside the screen (has the large rubber wire that goes to the tube). Generally one or two of the dials control focus and the other is the voltage fed to the screen, if the background is always washed out reducing voltage will get rid of the washout and hopefully reduce buzzing. When I have turned up the voltage too high I had buzzing and even popping if way too high,

Also remember if you turn the focus dial instead of the voltage (background brightness) dial all that happens is you have an opportunity to focus the screen Smile

I recommend a plastic screwdriver to do it (but personally never used one except at the school lab)

You normally need to do the adjustment while the screen is on with an image displayed that has both light and black areas, photos work nice. With the brightness dial about 1/3 of the way up, Turn the HV dial down until the white in the black areas of the screen dissappears. You can also adjust the color balance if you wish but I don't recommend it (normally off the gun circuit board that attaches to the tube)

Good Luck getting the IBM security screws out to do the above adjustment Smile
View user's profileSend private messageVisit poster's website
386er



Joined: 27 Jan 2007
Posts: 274
Location: USA

PostPosted: Tue Aug 10, 2010 4:24 am Reply with quoteBack to top

btw, i got another one from my temp job. e-waste bin Sad took it apart, and luckily had the security torx bits. found a small coil with white paint on it that came off a peice of ferrite material, stuck it back on and tested it. works great. no blur or screech or burning smell! date on the tag says april of 87. when these things came out?
View user's profileSend private messageSend e-mailMSN Messenger
Display posts from previous:      
Post new topicReply to topic
 Jump to:   
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001/3 phpBB Group :: FI Theme :: All times are GMT