I am Mohammed alaa el din from Cairo -Egypt ,
I will be 22 years old in 12 February and I love electronic work so much and I worked in repairing CRT monitors for 3 years approximately and in main board repairing too but there is big problem in TVs here in Egypt as I think !!
when we know that fly back in the TV is bad and try to change it and because of this TVs is so old and users of it let it so dirty this makes our work specially in removing fly back so hard in some cases when we try to remove it we listen to sound of scratch and chassis may be damaged.
Mr. Humphrey when you come in Egypt you are welcomed in my new shop that I will open on 7th February.
Thank for your email and glad to hear from Cairo-Egypt, Also I have noted you have a passion in electronics and this is very good Characteristic of smart technicians.
Usually when you receive a Television in your shop it is always a good practice to clean the dust with a soft brush(like small paint brush) and do some blowing but be sure you do it outside your shop to avoid messing up your room with dust which is healthy hazard.
To remove the fly back transformer from the circuit you need higher wattage Iron gun and solder sucker (this one is a must) and be sure you suck the solder on all the fly back pins.
Then using a big flat screwdriver try to push between the fly back body and the circuit board and rotate the screw driver slowly and carefully until the fly back come out.
Please don’t use force otherwise you are going to break the board, if you find still the fly back is not coming out easily this could mean there is still a strong joint and should be checked and solder it out.
Fly back transformer can fail in many ways which includes overheating leading to cracks in the plastic and external arcing. These can often be fixed by cleaning and coating with multiple layers of high voltage sealer, Cracked or damaged core, Internal shorts in the FOCUS/SCREEN divider network, internal short circuits in the windings and open windings among others.
First, perform a careful visual inspection with power off. Look for cracks, bulging or melted plastic, and discoloration, Look for bad solder connections at the pins of the fly back as well.
If the TV can be powered safely, check for arcing around the fly back.
Please note that a short on the primary winding of the fly back can only be tested using a fly back tester, if you don’t have one you can easily make one. I have documented how to make one elsewhere on this blog you can check it out.
I wish you the best on the opening of your new shop and hope you send me some pictures on the same.
All the best Mohammed.
For those who would like to see Cairo city (Video) click this link.
DEAR AALA DINReplyDelete
if you find out that the fly back transformer is calprit
to find the exact fly back transformer is another problem for repairer . if you find a new one . you must becareful about the price of it . some time the price of a new flyback transformer is more than a tv that you are working on it in this case you have to consult with the customre about the price of total repair amount
Thank you for your contribution on this MR.Beh.ReplyDelete