Riddled TV Repair Forum
Service Menu and Manual Schematics
 
   
 FAQFAQ   SearchSearch   RegisterRegister 
   Log inLog in 
Sylvania LC220SS1 blown fuse, diodes replaced, kind-of!    
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair
 
Author Message
ronald_herrera



Joined: 15 Jun 2014
Posts: 3
Location: Puerto Rico

PostPosted: Sun Jun 15, 2014 4:27 pm    Post subject: Sylvania LC220SS1 blown fuse, diodes replaced, kind-of! Reply with quote

Hello, I have changed "rectifier diodes?" d601 and d603 both 1n5397, other diodes was OK. But since, I do not have money or much spare parts, I replaced with a similar: 1n5399 diodes. And something called a zener diode d612 (1zb220-y), I replace it with a funny looking zener that looks much a like of what I could find or have at the moment: [456201]. Since this zener was on a CRT TV board and the symbol looks a like of the one that was damaged, I took a chance since I couldn't understand the specifications in a datasheet (a paper that contains a bunch of number in it).

Ok, I know how test the diodes (with a very old analog ohm meter) and managed to know it's purpose (more or less). So the TV that my neighbor was about to through away, it worked miraculously without blowing a fuse. The main question for you guys, how much it will last with the replaced parts described above considering the difference in value?

Thanks for your patience. (Sorry about my English).
Google

PostPost subject: Advertisement

kuhurdler



Joined: 28 Dec 2006
Posts: 2847
Location: Overland Park, KS

PostPosted: Thu Jun 19, 2014 9:23 am    Post subject: Reply with quote

In my opinion, it could die at any moment.

I'd be most concerned with the zener you used... you could be providing over or under voltage if it's not the same voltage rating.

If the other diodes go, they'll "probably" not cause too much damage.
ronald_herrera



Joined: 15 Jun 2014
Posts: 3
Location: Puerto Rico

PostPosted: Thu Jun 19, 2014 1:51 pm    Post subject: Reply with quote

Okay! That's what I also thought. The original rectifier diodes that makes a bridge are 1n5397 which blocks voltage that goes upto 600, but the one that I install is 1n5399 that can block 1000v. I'm guessing that a reverse voltage from the transformer can be hitting the diodes to die more quickly that it suppose to; specially when, for any reason, power voltage drops by the source in the outlet. The other two diodes are original from the circuit that I have removed just a pin and tested with a analog meter.

As you say, the zener diode is another story, because I couldn't identify it in the net. I don't really know it's real value. Since the original is a 1nzb220 and the one that is replacing it has a number: 456 201 (if numbers are right) I thought if could do the job. I also observe that other similar power boards for the same TV model they didn't include a zener, or it's empty on d612. Which makes me think that probably it's was thought to be in case of a power surge.

Anyhow, thank you for answering, if you have any other data that I should be aware, please, let me know.

My best regards.
Ron.
kuhurdler



Joined: 28 Dec 2006
Posts: 2847
Location: Overland Park, KS

PostPosted: Fri Jun 20, 2014 9:27 am    Post subject: Reply with quote

D612 DIODE ZENER 1ZB220-YBB NDWZ01ZB220Y
It's a 220V zener
http://pdf.datasheetcatalog.com/datasheet/toshiba/3586.pdf

Diodes have other design considerations besides voltage. Response time, and current ratings are two major ones I can think of. I'd assume based on the model numbers you listed, it will be fine.

here's a service manual for your model: http://www.encompassparts.com/shop/asf/syl/FL10_1_FUN_SM_AEN_072910.pdf
ronald_herrera



Joined: 15 Jun 2014
Posts: 3
Location: Puerto Rico

PostPosted: Fri Jun 20, 2014 6:03 pm    Post subject: Reply with quote

Okay good! Thank you, kuhurdler, very much; I appreciate it.

You know, this is a good TV and it was going to be thrown away because of a malfunction that, I can speculate, of a power surge short away first the zener, I'm guessing. And because of that, 2 of the 4 rectifiers of the bridge shorten out causing the fuse to blow. I make sure to use the same fuse (125V 4A) in case it happens again. I was lucky enough that is was none of the transistors (MOS q601 or the little one q602) because I really don't have those parts.

So, I placed the equipment directly to a surge protector multi-outlet thing in order to reduce the risk of getting it fried again. Something that my neighbor (the original owner) didn't do specially when his electrical house power is not that stable. Well, he bought a new one. My point here is, that this TV has now a value between $50 to $150 and at this moment I'm still enjoying it; working very well for the time been.

I'm pretty excited because I was able to be bold enough to actually repair a technology that I thought it was only for respected technicians that could have charged me $50 for the repair, plus parts (even though, I still think that will be a good idea because the TV was worth saving and the tech. could extended some guaranty for his work). The point is that I don't have any money and probably it was going to be thrown away. "And for this time", the task it was fairly simple for anyone (obviously respecting the safety to avoid personal risks) to fix it out without not knowing much of electronics.

Getting back to the issue here, thank you guys for your support and I have found some diodes that match the original values of the one that I replace with, except for the zener. That one I'm still looking for.

Sorry for my English (I'm practicing. That's why I write quite a bit, if anyone has to know). Very Happy
Google

PostPost subject: Advertisement

Display posts from previous:   
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair All times are GMT - 6 Hours
Page 1 of 1

 


Disclaimer: All information provided by RiddledTV is strictly for information purposes only. Please observe all warnings displayed on your electronic
devices. This information should only be used to help diagnose work, and all service should be performed by a qualified technician.
Contact Us       Privacy Policy       Copyright © 2015 RiddledTV.com       Advertise on RiddedTV.com