Jorges : I had already disconnected the collector from
board, and the snubber and diode that goes to pin 1 of fly back and still there
is short to that pin from ground. Sir this is hard. Do you think maybe I go
check elsewhere else, or is it time to do voltage testing...although there is
short?
Humphrey: Components that can short on that line are very
few...and the way you put it it’s like the short is after the fly back...These
include HOT, snubber capacitor. The yoke (horizontal), dis- connect the yoke connector at the
circuit board and test again...short gone?
Jorges: Sir I have done this. Just in case I also disconnect
the lines from board to CRT Neck too. Still there is a Short.
Humphrey: just follow that line removing one leg of the
component at a time until the short disappear...Very few components
though...and come back to me.
Jorges: Ok Mr. Humphrey, This is what I did. After I check
from ground to (secondary) cathode of diode and next way there was a short on
the b+. This line goes to pin 2 of FBT. Before it reaches FBT it passes the
white resistor 3.9 ohm that got hot. It’s like the surge but this is on the
line to pin2 of fly back.
When I disconnect all component after the secondary diode
which test good (when I lift one leg) up to Pin2 the short is still there. So I
lift pin2 and the short on the line is gone. But when I touch the probe to pin2
that is disconnected it shows short. Because there should be ohms to Pin1 to
Pin2, I disconnect the collector of hot from pin one and also the snubber,
diode, and another capacitor from this line. If I now touch pin 2 with the
probe it still shows short to ground.
I de solder pin1 (collector) and test and Pin1 and Pin2
still show short to ground.
I removed the fly back from board and there is short from
the ground pin5 to Pin1 and Pin2 of fly back. Also when the light was blinking
(TV was on) there is a tic, tic sound in fly back. I don't understand fly back
much, but you can bet sir that I am going over that Chapter in your book again
for the fourth time. Thanks.
Humphrey: or could it be the culprit is the fly back itself?...I smell a rat here... there is no
way the B+ pin on the fly back resistance to the ground have continuity.
Jorges: Thanks for the tip on smelling a rat. I opened the
FBT and what do you know, it is leaking all inside. I went to an old TV repair
shop and got a used replacement. What do you know, like my teacher I like what
my ears heard.. And I had to adjust focus and brightness a bit and I like what
my eyes see. Thanks
I find it strange that the HOT is good, since I didn't
replace it or the snubber, I tell the owner there is chance TV will only run
for a while, but he is in too much hurry to wait for part, so he knows the
risk.
This eBook has made me learn in 2 weeks, what I wanted to do for so long.
It is so practical and now I am even checking HOT Out from IC's, the Horizontal
Yoke, and directly go to suspect Filter Caps on VCC Power IC, Current sense
resistor and more. Thank you!!!
Wishing you all the Best Jorges...
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