CTC169 36" dead
 

Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but the
set still is dead. HOT is fine, chopper is running. I dont know what to look
for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

CTC169 36" dead
 

Mike wrote:
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but the
set still is dead. HOT is fine, chopper is running. I dont know what to look
for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

Hi...

Take a look at the 15v supply, if there's a fair bit of ac ripple there,
go ahead and change c4145.

Take care.

Ken

CTC169 36" dead
 

i used an ESR meter. the cap has very good ESR, i shoudl change it though.
but nothing makes since. the 13.3v is solid, even when you press power
button, unlike before. i thought its supposed to raise when power pressed,
it doesnt.




"Ken Weitzel" wrote in message
news:29Auh.821460$R63.244561@pd7urf1no...
Mike wrote:
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

Hi...

Take a look at the 15v supply, if there's a fair bit of ac ripple there,
go ahead and change c4145.

Take care.

Ken

CTC169 36" dead
 

im going to scope it and be sure. good point. ;-)



"Ken Weitzel" wrote in message
news:29Auh.821460$R63.244561@pd7urf1no...
Mike wrote:
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

Hi...

Take a look at the 15v supply, if there's a fair bit of ac ripple there,
go ahead and change c4145.

Take care.

Ken

CTC169 36" dead
 

i think something somewhere is funky. I scoped out the 15v standby, it looks
like sawtooth, with a ringing on the up-ramps.


when i press power, you can here the supply "tick" and the sawtooth gets
considerably larger, and then drops back down the way it does. the cycle
repeats each time i hit power.

i scoped the 26v source from the power supply, it also has this "sawtooth"
ripple, but its considerably smaller. although still preseant.


any ideas?


"Mike" wrote in message
...
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

CTC169 36" dead
 

i replaced the cap off of the 15V standby, and i still get the same ****. im
at a standstill im assuming somethign is loading the standby down, shorted
somewhere.


as the set only fired up once wiht HV. and never did it again.

the HOT tests fine.



"Mike" wrote in message
...
i think something somewhere is funky. I scoped out the 15v standby, it
looks like sawtooth, with a ringing on the up-ramps.


when i press power, you can here the supply "tick" and the sawtooth gets
considerably larger, and then drops back down the way it does. the cycle
repeats each time i hit power.

i scoped the 26v source from the power supply, it also has this "sawtooth"
ripple, but its considerably smaller. although still preseant.


any ideas?


"Mike" wrote in message
...
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

CTC169 36" dead
 

i think its the horiz circuit.


When i press power, pin26 of U1001 jumps to about 8.6 volts. holds it for
about 3 to 5 seconds, and drops back down. jumps back up each time i press
power.

there is NO drive on the HOT. on any attempt. even on plugin. no drive.
somethings up.




"Mike" wrote in message
...
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

CTC169 36" dead
 

Mike wrote:
i think its the horiz circuit.


When i press power, pin26 of U1001 jumps to about 8.6 volts. holds it for
about 3 to 5 seconds, and drops back down. jumps back up each time i press
power.

there is NO drive on the HOT. on any attempt. even on plugin. no drive.
somethings up.

Weird.... the 26 volts you mentioned was present in a previous message
is derived from horizontal scan... ???

Ken

CTC169 36" dead
 

no. from the chopper.


"Ken Weitzel" wrote in message
news:EYPuh.809791$1T2.414831@pd7urf2no...
Mike wrote:
i think its the horiz circuit.


When i press power, pin26 of U1001 jumps to about 8.6 volts. holds it for
about 3 to 5 seconds, and drops back down. jumps back up each time i
press power.

there is NO drive on the HOT. on any attempt. even on plugin. no drive.
somethings up.

Weird.... the 26 volts you mentioned was present in a previous message is
derived from horizontal scan... ???

Ken

CTC169 36" dead
 

i have nothing from the horiz circuit. the horiz circuit has failed.

i think U1001 is bad.

i removed the horiz drive xistor. when power is pressed, NO waveform on the
base of the transistor. im looking for a strong saw or square wave i assume.
well i have nothing but a little bit of noise when the power is pressed. and
i have to crank the scope up to see it.

now if i scope out pin 23, the H-drive out. i have the same type of noise,
but a little bit bigger in amplitude.

shouldnt i have a strong defined square pulse? at 15.25khz. well i get a
faint bit of noise. almost like a ring type of noise.


when power is pressed, the 9v VCC to the hoiz osc of U1001 goes present. so
whats left. U1001?



"Ken Weitzel" wrote in message
news:EYPuh.809791$1T2.414831@pd7urf2no...
Mike wrote:
i think its the horiz circuit.


When i press power, pin26 of U1001 jumps to about 8.6 volts. holds it for
about 3 to 5 seconds, and drops back down. jumps back up each time i
press power.

there is NO drive on the HOT. on any attempt. even on plugin. no drive.
somethings up.

Weird.... the 26 volts you mentioned was present in a previous message is
derived from horizontal scan... ???

Ken

CTC169 36" dead
 

Mike wrote:
i have nothing from the horiz circuit. the horiz circuit has failed.

i think U1001 is bad.

i removed the horiz drive xistor. when power is pressed, NO waveform on the
base of the transistor. im looking for a strong saw or square wave i assume.
well i have nothing but a little bit of noise when the power is pressed. and
i have to crank the scope up to see it.

now if i scope out pin 23, the H-drive out. i have the same type of noise,
but a little bit bigger in amplitude.

shouldnt i have a strong defined square pulse? at 15.25khz. well i get a
faint bit of noise. almost like a ring type of noise.


when power is pressed, the 9v VCC to the hoiz osc of U1001 goes present. so
whats left. U1001?

Hi...

What's the voltage on pin 16 u4101? (power on, let it run for a few
seconds while you watch - wandering around?)

Take care.

Ken

CTC169 36" dead
 

no. stays a solid 51.6vdc



"Ken Weitzel" wrote in message
news:JMTuh.814133$5R2.803438@pd7urf3no...
Mike wrote:
i have nothing from the horiz circuit. the horiz circuit has failed.

i think U1001 is bad.

i removed the horiz drive xistor. when power is pressed, NO waveform on
the
base of the transistor. im looking for a strong saw or square wave i
assume.
well i have nothing but a little bit of noise when the power is pressed.
and
i have to crank the scope up to see it.

now if i scope out pin 23, the H-drive out. i have the same type of
noise,
but a little bit bigger in amplitude.

shouldnt i have a strong defined square pulse? at 15.25khz. well i get a
faint bit of noise. almost like a ring type of noise.


when power is pressed, the 9v VCC to the hoiz osc of U1001 goes present.
so
whats left. U1001?

Hi...

What's the voltage on pin 16 u4101? (power on, let it run for a few
seconds while you watch - wandering around?)

Take care.

Ken

CTC169 36" dead
 

i moved my ground probe to the negative side of the primary, i had it on the
negative side of the secondary, this time i get a rock solid 10.2v



"Ken Weitzel" wrote in message
news:JMTuh.814133$5R2.803438@pd7urf3no...
Mike wrote:
i have nothing from the horiz circuit. the horiz circuit has failed.

i think U1001 is bad.

i removed the horiz drive xistor. when power is pressed, NO waveform on
the
base of the transistor. im looking for a strong saw or square wave i
assume.
well i have nothing but a little bit of noise when the power is pressed.
and
i have to crank the scope up to see it.

now if i scope out pin 23, the H-drive out. i have the same type of
noise,
but a little bit bigger in amplitude.

shouldnt i have a strong defined square pulse? at 15.25khz. well i get a
faint bit of noise. almost like a ring type of noise.


when power is pressed, the 9v VCC to the hoiz osc of U1001 goes present.
so
whats left. U1001?

Hi...

What's the voltage on pin 16 u4101? (power on, let it run for a few
seconds while you watch - wandering around?)

Take care.

Ken

CTC169 36" dead
 

Mike wrote:
i moved my ground probe to the negative side of the primary, i had it on the
negative side of the secondary, this time i get a rock solid 10.2v

Right where it should be; indicates that the set "isn't turning on" as
opposed to being held off by its own protection circuits.

My address is good; send me an email from an address that can take a
few megs of attachment. And if necessary, do whatever you have to so
that attachments from me are acceptable

Take care.

Ken

CTC169 36" dead
 

ok.

maybe a picture is worth a thousand words.


here is the scoped output of the 15v standby. also the same waveform is
present on all the outpus of the power supply. the waveform gets a little
bit larger when the power button is pressed.

http://pubserver1.ath.cx/scope.jpg

Also, you see the ringing on the peaks? well when i scope the output of the
U1001 to the driver transistor, i get a flat line, with the same exact
ringing. but no square output. horiz VCC goes to 9v when power is pressed,
and drops back to 0v approximately 3 to 4 seconds later.

im not sure what the issue is. looks liek something is seriosuly loading the
supply. but im not sure. all 4 caps in the primary have been replaced, and
the cap on the 15v CR4118 was replaced, along wiht CR4118.


"Ken Weitzel" wrote in message
news:_Wrvh.818822$5R2.368620@pd7urf3no...
Mike wrote:
i moved my ground probe to the negative side of the primary, i had it on
the negative side of the secondary, this time i get a rock solid 10.2v

Right where it should be; indicates that the set "isn't turning on" as
opposed to being held off by its own protection circuits.

My address is good; send me an email from an address that can take a
few megs of attachment. And if necessary, do whatever you have to so that
attachments from me are acceptable

Take care.

Ken

CTC169 36" dead
 

im assuming the "ringing" is the power supply turning on to charge up the
caps to get the voltage back to what it shoudl be, and the steady decline is
the caps discharging, then hits the threshold, and supply starts again.



"Mike" wrote in message
...
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

CTC169 36" dead
 

for the hell of it, i disconnected the amplifier board completely from the
circuit, all plugs, and unsoldered the entire board.


the ramp pulse with ringing is still present on the power supply.

but now, when i scope U1001, when i press power, my pulse is showing up now.
it wasnt before. wtf...



"Mike" wrote in message
...
im assuming the "ringing" is the power supply turning on to charge up the
caps to get the voltage back to what it shoudl be, and the steady decline
is the caps discharging, then hits the threshold, and supply starts again.



"Mike" wrote in message
...
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

CTC169 36" dead
 

nevermind, i spoke too soon. its gone again :-(

im guessing either the ramp noise from the output of the supply is
disturbing the IC, or U1001 is intermittantly defective. :-\



"Mike" wrote in message
...
for the hell of it, i disconnected the amplifier board completely from the
circuit, all plugs, and unsoldered the entire board.


the ramp pulse with ringing is still present on the power supply.

but now, when i scope U1001, when i press power, my pulse is showing up
now. it wasnt before. wtf...



"Mike" wrote in message
...
im assuming the "ringing" is the power supply turning on to charge up the
caps to get the voltage back to what it shoudl be, and the steady decline
is the caps discharging, then hits the threshold, and supply starts
again.



"Mike" wrote in message
...
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby
is about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very
faintly, like a weak supply somewhere.

any ideas?

CTC169 36" dead
 

it was audio out board. i plugged the horiz driver xistor back in. its not
dead anymore. although somtiems it turns on now. sometimes it doesnt. but if
i plug the audio board back up. it wont work at all.



"Mike" wrote in message
...
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

CTC169 36" dead
 

Mike wrote:
it was audio out board. i plugged the horiz driver xistor back in. its not
dead anymore. although somtiems it turns on now. sometimes it doesnt. but if
i plug the audio board back up. it wont work at all.

Hi..

When it won't turn on (with audio disconnected) take a look at pin 22 of
1001. If it's more than 1.5v, something else is in protection mode.

Take care.

Ken

CTC169 36" dead
 

well then it has to be a cap or somethign liek that. because when it does
turn on, it plays beautifully. perfect pictuer. just no audio. ;-)



"Mike" wrote in message
...
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

CTC169 36" dead
 

ok i replaced the last 2 capacitors on teh secondary of the main SMPS unit,
the set now comes on and works every time. YAY. finally. but the audio is
dead. as soon as you plug in that little conenctor, to power up the audio
amp, set wont start at all. no horiz pulse, like before. the power supply is
smooth now. at least until you plug in the audio connector. then the power
supply loads down again.


"Mike" wrote in message
...
well then it has to be a cap or somethign liek that. because when it does
turn on, it plays beautifully. perfect pictuer. just no audio. ;-)



"Mike" wrote in message
...
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby is
about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very faintly,
like a weak supply somewhere.

any ideas?

CTC169 36" dead
 

i need a cross reference and/or schematic/datasheet to the audio out IC.
only markings on it is 51135, assuming a factory assy run number or some
cryptic code.




"Mike" wrote in message
...
ok i replaced the last 2 capacitors on teh secondary of the main SMPS
unit, the set now comes on and works every time. YAY. finally. but the
audio is dead. as soon as you plug in that little conenctor, to power up
the audio amp, set wont start at all. no horiz pulse, like before. the
power supply is smooth now. at least until you plug in the audio
connector. then the power supply loads down again.


"Mike" wrote in message
...
well then it has to be a cap or somethign liek that. because when it does
turn on, it plays beautifully. perfect pictuer. just no audio. ;-)



"Mike" wrote in message
...
Got this set, it would turn on and fire HV for a second, then shut back
down. it wont do it anymore, only did it one time.


I monitored C4118 while pressing the button, it would start off at 13.1
volts, and drop down to about 5 volts. when power button was pressed.


I then replaced CR4118, and replaced 2 caps in the IC chip of the power
supply. the main B+ at standby levels is about 143vdc. the 15v standby
is about 13.3 still.


but this time, when you press the power button, OR perform the manual
power-on, bypassing the micro unit, the voltage doesnt drop anymore, but
the set still is dead. HOT is fine, chopper is running. I dont know what
to look for next.

however if i hold the board in manual power on, every once in awhile the
degauss relay would start clicking on and off a little bit, very
faintly, like a weak supply somewhere.

any ideas?