I meet a gentleman on my way to my place work and mentioned
to me that he has a television which need repair and therefore I can pick it up
on my way home.
I passed by his place and the television was already send to
the store since he has another small size which he was now using to keep up
with the news since we have elections here in Kenya around the corner.
So I had no time to test the television on site to confirm
what he said was the problem, initially he has told me the television was just
dead.
I took the television and within ten minutes I was in my
workshop, I applied power and the television fired well but there was a
horizontal line across the screen as you see below.
With that even before opening I concluded the problem was on
the vertical circuit and therefore proceeded to open the set and my attention
was focused on the vertical circuit.
The television was using I.C LA78040N, I scanned around this
circuit and did not see any suspect,
I continued scanning around the circuit and I noted a small
capacitor with the top slightly swollen and I was interested to see if it is
part of the vertical circuit.
The capacitor reference was C515 (1000uF/25V) as you can see
below.
I googled this model to see exactly which circuit this
capacitor serves and here is what I got…
Yes, this capacitor is part of the vertical circuit and
right at the output of the vertical circuit and therefore failure on this
capacitor is capable of causing the symptoms above.
I pulled it out of the circuit and tested its ESR and this
is what I got 77.6 ohms!!…usually a good capacitor of this value (1000uF/25V)
should be less than 0.5 ohms.
I also decided to do further test using my multi-component
tester and this what is got.
As you can see the capacitor was rated 1000uF but now it is
reading on 27pF, SAD!
I replaced the capacitor with a new one rated 1000uF/50 V
from my capacitor kit (120 Pcs 15 Value50V Electrolytic Capacitor 1UF-2200UFohm Assortment Kit) I have ordered online
and having found no other culprit around that circuit I decided to test the
television to see if the problem has gone or not and this is what I saw.
IAAF WORLD U18 CHAMPIONSHIPS NAIROBI 2017 at Kasarani sport
center LIVE
THANKS LIKE YOUR ESR METER PLEASE LET ME KNOW HOW MUCH IT COST AND FROM WHERE CAN I BUY ONE.
ReplyDeleteTHANKS
BASHEER
Hi Khan, this model is no longer in the market but now we have MK-328 multi component tester which is listed for sale on this blog.
DeleteRegards Humphrey