Convergence problem
 

Hitachi 50EX10B. I have the convergence looking almost perfect, except
I can't straighten out the bow (down) on the bottom of the screen
viewing cross hatch pattern. I had no control of blue, so I replaced
all the convergence amp IC's (figured good idea since the set is 11
years old). This fixed the blue problem. I can get about the center 2/3
of the bottom line to straighten, but both corners turn down, and no
conv. adjustment on the board removes this. I don't see where I can
adjust anything else to fix this. Is there another component at fault?
Thanks to all.

Bias resistors off the STK,s return .
kip
wrote in message
oups.com...
Hitachi 50EX10B. I have the convergence looking almost perfect, except
I can't straighten out the bow (down) on the bottom of the screen
viewing cross hatch pattern. I had no control of blue, so I replaced
all the convergence amp IC's (figured good idea since the set is 11
years old). This fixed the blue problem. I can get about the center 2/3
of the bottom line to straighten, but both corners turn down, and no
conv. adjustment on the board removes this. I don't see where I can
adjust anything else to fix this. Is there another component at fault?
Thanks to all.

kip wrote:
Bias resistors off the STK,s return .
kip
wrote in message
oups.com...
Hitachi 50EX10B. I have the convergence looking almost perfect, except
I can't straighten out the bow (down) on the bottom of the screen
viewing cross hatch pattern. I had no control of blue, so I replaced
all the convergence amp IC's (figured good idea since the set is 11
years old). This fixed the blue problem. I can get about the center 2/3
of the bottom line to straighten, but both corners turn down, and no
conv. adjustment on the board removes this. I don't see where I can
adjust anything else to fix this. Is there another component at fault?
Thanks to all.


Thanks for the info Kip. I'll look over the schematic to try to find
these and test(I'm fairly new in repair). I'll post with results. Do
these usually short, or drift way off value?

it would be very odd if a resistor should go short semiconductors go short
not resistors,

Resistors go high or open circuit.


wrote in message
oups.com...

kip wrote:
Bias resistors off the STK,s return .
kip
wrote in message
oups.com...
Hitachi 50EX10B. I have the convergence looking almost perfect, except
I can't straighten out the bow (down) on the bottom of the screen
viewing cross hatch pattern. I had no control of blue, so I replaced
all the convergence amp IC's (figured good idea since the set is 11
years old). This fixed the blue problem. I can get about the center 2/3
of the bottom line to straighten, but both corners turn down, and no
conv. adjustment on the board removes this. I don't see where I can
adjust anything else to fix this. Is there another component at fault?
Thanks to all.


Thanks for the info Kip. I'll look over the schematic to try to find
these and test(I'm fairly new in repair). I'll post with results. Do
these usually short, or drift way off value?

Look around the STK,s for low value about 1.2 to 2.0 ohm close tolerance
resistors.

kip
wrote in message
oups.com...

kip wrote:
Bias resistors off the STK,s return .
kip
wrote in message
oups.com...
Hitachi 50EX10B. I have the convergence looking almost perfect, except
I can't straighten out the bow (down) on the bottom of the screen
viewing cross hatch pattern. I had no control of blue, so I replaced
all the convergence amp IC's (figured good idea since the set is 11
years old). This fixed the blue problem. I can get about the center 2/3
of the bottom line to straighten, but both corners turn down, and no
conv. adjustment on the board removes this. I don't see where I can
adjust anything else to fix this. Is there another component at fault?
Thanks to all.


Thanks for the info Kip. I'll look over the schematic to try to find
these and test(I'm fairly new in repair). I'll post with results. Do
these usually short, or drift way off value?

Hey Resistors go high and low in value in those circuits

kip...

"Eric" wrote in message ...
it would be very odd if a resistor should go short semiconductors go short
not resistors,

Resistors go high or open circuit.


wrote in message
oups.com...

kip wrote:
Bias resistors off the STK,s return .
kip
wrote in message
oups.com...
Hitachi 50EX10B. I have the convergence looking almost perfect, except
I can't straighten out the bow (down) on the bottom of the screen
viewing cross hatch pattern. I had no control of blue, so I replaced
all the convergence amp IC's (figured good idea since the set is 11
years old). This fixed the blue problem. I can get about the center 2/3
of the bottom line to straighten, but both corners turn down, and no
conv. adjustment on the board removes this. I don't see where I can
adjust anything else to fix this. Is there another component at fault?
Thanks to all.


Thanks for the info Kip. I'll look over the schematic to try to find
these and test(I'm fairly new in repair). I'll post with results. Do
these usually short, or drift way off value?

kip wrote:
Hey Resistors go high and low in value in those circuits

kip...

"Eric" wrote in message ...
it would be very odd if a resistor should go short semiconductors go short
not resistors,

Resistors go high or open circuit.


wrote in message
oups.com...

kip wrote:
Bias resistors off the STK,s return .
kip
wrote in message
oups.com...
Hitachi 50EX10B. I have the convergence looking almost perfect, except
I can't straighten out the bow (down) on the bottom of the screen
viewing cross hatch pattern. I had no control of blue, so I replaced
all the convergence amp IC's (figured good idea since the set is 11
years old). This fixed the blue problem. I can get about the center 2/3
of the bottom line to straighten, but both corners turn down, and no
conv. adjustment on the board removes this. I don't see where I can
adjust anything else to fix this. Is there another component at fault?
Thanks to all.


Thanks for the info Kip. I'll look over the schematic to try to find
these and test(I'm fairly new in repair). I'll post with results. Do
these usually short, or drift way off value?

Thankyou all for the valuable info. I will post as soon as I check this out.

kip wrote:
Look around the STK,s for low value about 1.2 to 2.0 ohm close tolerance
resistors.

kip
wrote in message
oups.com...

kip wrote:
Bias resistors off the STK,s return .
kip
wrote in message
oups.com...
Hitachi 50EX10B. I have the convergence looking almost perfect, except
I can't straighten out the bow (down) on the bottom of the screen
viewing cross hatch pattern. I had no control of blue, so I replaced
all the convergence amp IC's (figured good idea since the set is 11
years old). This fixed the blue problem. I can get about the center 2/3
of the bottom line to straighten, but both corners turn down, and no
conv. adjustment on the board removes this. I don't see where I can
adjust anything else to fix this. Is there another component at fault?
Thanks to all.


Thanks for the info Kip. I'll look over the schematic to try to find
these and test(I'm fairly new in repair). I'll post with results. Do
these usually short, or drift way off value?

I checked all the resistors and all OK. I initialized the system to
reset to factory, and started from scratch. I managed to get the
covergence acceptable, (but with a slight bow on bottom still). Set
looks good. Thanks again.