Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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  #1   Report Post  
woodward_electric
 
Posts: n/a
Default Rca ctc203aa5

This set is totally dead. I did the repairs on L14101

Power supply chirps when line cord is plugged in.

Have followed the trouble shooting guide. I do not have a chipper checker and the set will not start with the menu,power, vol command

The 5v regulated voltage is present at all times. When the power button is pressed the 2.5v appears on j13301 pin 18 and the 12v appears on the 12v regulator u 14404. Both voltages disappear within a second or two and they do not pulse they just die. Set has to be unplugged before it will respond to the power button again. when power button is pushed
5.2v is present on j13104 pin 7
1.6v is present on pin 10
4.8v is present on pins 4, 6, and 8

unsoldered output collector and j10303 pin 13 will show the 12v for 2 seconds and it disappears it does not pulse at all

Help would be greatly appreciated

Thanks in advance

Lance




  #2   Report Post  
Jason D.
 
Posts: n/a
Default Rca ctc203aa5

unsoldered output collector and j10303 pin 13 will show the 12v for 2 =
seconds and it disappears it does not pulse at all

Help would be greatly appreciated

Thanks in advance

Lance


Lance,

First: MODEL NUMBER!?

If you have measured the resistance of that Q14401 (horizontal
transistor), it is shorted hence the chirping power supply.

What blew this transistor was the bad solder joint on the L14401 a
ferrite rod wrapped with wire (coil) because of glue. Remove that
L14401 and clean glue off, unplug one hole clogged with glue.
Reinstall coil and new horizontal transistor.

This should fix up that set.

Cheers,

Wizard

Cheers,

Wizard
  #3   Report Post  
Jason D.
 
Posts: n/a
Default Rca ctc203aa5

unsoldered output collector and j10303 pin 13 will show the 12v for 2 =
seconds and it disappears it does not pulse at all

Help would be greatly appreciated

Thanks in advance

Lance


Lance,

First: MODEL NUMBER!?

If you have measured the resistance of that Q14401 (horizontal
transistor), it is shorted hence the chirping power supply.

What blew this transistor was the bad solder joint on the L14401 a
ferrite rod wrapped with wire (coil) because of glue. Remove that
L14401 and clean glue off, unplug one hole clogged with glue.
Reinstall coil and new horizontal transistor.

This should fix up that set.

Cheers,

Wizard

Cheers,

Wizard
  #4   Report Post  
Lance Dyer
 
Posts: n/a
Default Rca ctc203aa5

Hi Jason
the model is a F27649

This set is totally dead. I did the repairs on L14101

Power supply chirps when line cord is plugged in.

Have followed the trouble shooting guide. I do not have a chipper checker
and the set will not start with the menu,power, vol command

The 5v regulated voltage is present at all times. When the power button is
pressed the 2.5v appears on j13301 pin 18 and the 12v appears on the 12v
regulator u 14404. Both voltages disappear within a second or two and they
do not pulse they just die. Set has to be unplugged before it will respond
to the power button again. when power button is pushed
5.2v is present on j13104 pin 7
1.6v is present on pin 10
4.8v is present on pins 4, 6, and 8

unsoldered output collector and j10303 pin 13 will show the 12v for 2
seconds and it disappears it does not pulse at all

as stated I already did the coil L14401 and the horizontal output is good
even subbed it just in case. The chirp I was refering to is the chirp of
the power supply when pluged into the line voltage. It will chirp just once
with startup surge. On the collector of the horizontal output is 138v
regulated voltage. Could this be a problem with the Gemstar module as
system control is integrated to it or do I have a data clock line problem.
I unplugged j13104 to try and isolate problen and had the same results on
the above tests.

"Jason D." wrote in message
...
unsoldered output collector and j10303 pin 13 will show the 12v for 2 =
seconds and it disappears it does not pulse at all

Help would be greatly appreciated

Thanks in advance

Lance


Lance,

First: MODEL NUMBER!?

If you have measured the resistance of that Q14401 (horizontal
transistor), it is shorted hence the chirping power supply.

What blew this transistor was the bad solder joint on the L14401 a
ferrite rod wrapped with wire (coil) because of glue. Remove that
L14401 and clean glue off, unplug one hole clogged with glue.
Reinstall coil and new horizontal transistor.

This should fix up that set.

Cheers,

Wizard

Cheers,

Wizard



  #5   Report Post  
Lance Dyer
 
Posts: n/a
Default Rca ctc203aa5

Hi Jason
the model is a F27649

This set is totally dead. I did the repairs on L14101

Power supply chirps when line cord is plugged in.

Have followed the trouble shooting guide. I do not have a chipper checker
and the set will not start with the menu,power, vol command

The 5v regulated voltage is present at all times. When the power button is
pressed the 2.5v appears on j13301 pin 18 and the 12v appears on the 12v
regulator u 14404. Both voltages disappear within a second or two and they
do not pulse they just die. Set has to be unplugged before it will respond
to the power button again. when power button is pushed
5.2v is present on j13104 pin 7
1.6v is present on pin 10
4.8v is present on pins 4, 6, and 8

unsoldered output collector and j10303 pin 13 will show the 12v for 2
seconds and it disappears it does not pulse at all

as stated I already did the coil L14401 and the horizontal output is good
even subbed it just in case. The chirp I was refering to is the chirp of
the power supply when pluged into the line voltage. It will chirp just once
with startup surge. On the collector of the horizontal output is 138v
regulated voltage. Could this be a problem with the Gemstar module as
system control is integrated to it or do I have a data clock line problem.
I unplugged j13104 to try and isolate problen and had the same results on
the above tests.

"Jason D." wrote in message
...
unsoldered output collector and j10303 pin 13 will show the 12v for 2 =
seconds and it disappears it does not pulse at all

Help would be greatly appreciated

Thanks in advance

Lance


Lance,

First: MODEL NUMBER!?

If you have measured the resistance of that Q14401 (horizontal
transistor), it is shorted hence the chirping power supply.

What blew this transistor was the bad solder joint on the L14401 a
ferrite rod wrapped with wire (coil) because of glue. Remove that
L14401 and clean glue off, unplug one hole clogged with glue.
Reinstall coil and new horizontal transistor.

This should fix up that set.

Cheers,

Wizard

Cheers,

Wizard





  #6   Report Post  
john
 
Posts: n/a
Default Rca ctc203aa5

This was picked up from another site
some very useful info .
You will need Chipper Checker for this..

CTC203
#1

*IIC "Run" Bus Servicing Strategies
This Phrase means, I squared C
Preface

This chassis incorporates 3 two wire IIC system control buses. They are;
Standby, Run, and Gemstar. This article only addresses the Run Bus issue.
There is no reason why the same approach cannot be used to isolate troubles
in either Standby or Gemstar IIC Buses. However the Run Bus occupies far
more landscape in this chassis making it harder to analyze and isolate.

It is assumed by this writer that the technician using this information
possesses a reasonable & fundamental knowledge on usage of the Chipper
Checker, IIC bus system controlling, and logical troubleshooting skills.

The following is a strategy to help the technician troubleshoot of the "Run"
Data or Clock Bus in the new Thomson CTC203 consumer television chassis. My
findings so far have found the Thomson's Chipper Checker has helped to
diagnose several intermittent, and "Hard" failures in this chassis. Chipper
Checker is not the cure-all, Tell All instrument in the case of this IIC
problem. It was instrumental in indicating an error code of "16". This
error code indicated the Run Bus was being held to a Logic "0". The
following text and an antidote might be help tech localize and isolate the
device responsible for this condition.

The next step after using the Chipper Checker, is to measure the "Run" IIC
buses on U13101(3 & 4) at the instant the power is applied. There should be
communications sustained for at least 45 Milliseconds on each IIC bus. At
turn on there will be continuos activity on the RUN/CLK bus. These
communication signals will be 5 volts peak to peak. If you discover either
one of these are stuck low proceed with the following steps.

Some precautions before starting.....

Loose the solder wick. Please! In order for solder wick to be effective the
iron temperature must be very hot between 700~800 degrees. The practice of
using high soldering temperatures and the solder wick tends to retain too
much heat.. These high temperatures are too high and will break down the
adhesive used on the copper traces. Once the adhesive is broken down the
trace lifts off the board and then your are left with mess.

The Hakko 471 is an excellent choice for desoldering the components on this
board. Just keep the temperature between 600 ~ 625 degrees and avoid
prolonged contact to the traces. If wick must be used, use only thin stuff,
and keep it trimmed back so only fresh braid contacts the trace the needs to
be desoldered.

OK..... Here's the Strategy for Isolating Error "16"

Place a short between the Q14104(C & E) located @ Q7 of main CBA. This
turns "ON" the necessary B+ to all the peripheral IC's in the chassis. It
must be done otherwise the "Run" Data and Clock buses will be loaded down
because all of the peripheral IC's are are loading them down.
Next float U13101 (3 & 4) these are the "RUN" data and clock pins from the
U13101 CPU.
Next apply power to the set. No need to turn on the television.
Next measure the solder foils or lands where U13101 (3 & 4) were connected.
The buses are supposed to be pulled high by one external pull up resistor
R13166 and R13169 on the each line. They both lines should measure between 5
~ 5.3 volts. If not, you will need to find out why. It has been my
experience that one or the other is low. It is possible both may be low too
but if so you will probably find as common reason. I.E. cracked board, board
contamination, missing B+ to a peripheral.
Finding the load can be tricky. On two out of five occasions these lines did
not measure a low resistance to ground. Instead they measured about 13K each
using a Fluke 78 meter. But an analogue meter gave different readings on the
bad line, 3K on the bad compared to 10K on the good line. The other two
televisions had solder bridges in the tuner assembly that caused the lines
to be held to ground, and the last Television had a defective Audio MTS
decoder IC U11601. Apparently on the last chassis the Stereo decoder did not
send an acknowledgment to the CPU after the first polling of the
peripherals. Note: If this chassis does not receive a ACK from each
peripheral the set will not turn on and it will log an error relative to the
defective peripheral.
Once it has been determined which bus is low, locate jumper wires that
relate to the appropriate bus and desolder them one at a time. Always
checking the condition on the land of U13101. The best way is to attack this
problem is to "half" the circuit. This means measure one side, and break the
line somewhere in the middle of the circuit between the CPU and the
furthest point away. Obviously always monitor the line that's in trouble.
Disconnecting the jumpers will make it easier in the localize the branch &
isolation the peripheral or passive component responsible for the defect. Be
careful to limit movement the free end of these jumpers it may weaken the
foil on the soldered end and the pad will tear from the board.

Begin As soon as you see the troubled line go high (5.0 ~ 5.2) volts you
have found the branch. At this point you will need to follow the schematic
and isolate the active components i.e. F2PIP module, T-4 chip, Stereo
decoder. If all else fails then you may have a passive components. Chip
capacitors should not be ruled out as potential suspects.

Jumpers related to "Run" Data are JW13122, JW13124, JW13128, and JW12112
Jumper related to "Run" Clock are JW13120, JW13123, JW13127, **JC12103

** A "JC" is a Jumper Component. It may look like a small chip resistor with
the number "0" printed on it. Some manufactures call them zero ohm
resistors.




Example of a Logic "0" Data Bus Problem

I was recently involved in troubleshooting a model F36445 CTC203 where it
was determined the IIC bus was held to logic "0". After lifting jumper wire
JW12112 on the data line, the load on U13101 (4) climbed from 1.9 to 5.2
volts. This jumper coupled the data line to several passive components, in
the tuner and Stereo decoder circuit, along with active components U16601(
9) MTS decoder, and the U17401(19) tuner PLL controller. A decision had to
be made to cut a trace ( see silk screen) located adjacent to the tuner
shield, in order to isolate the short. If you have the Thomson ESI schematic
locate the tuner section. The short was located along the data bus that
controls the tuner PLL. Capacitor C17416 in the silk screen was the
culprit. Removing the capacitor and reconnecting the cut trace allowed the
data line to finally go high and the set was operating again.. Capacitor was
replaced wit part# 214029 a 43 pf surface mounted capacitor.




Clipped from another source..

#2

Place a jumper between Q14104(E & C) This will turn on the Switched 12
volts and apply power to the all the peripherals. Next, carefully remove the
pins of U13101(3 &4) and apply power to the set. Both traces on the data and
clock must be 5 volts. If it is 5 volts then no excessive loads on the Data
or clock lines exist. In this case U13101(3) was 1.9 volts. This indicated
that something that connected to the Data line was loading it down. All ICs
were isolated by removal of the data and clock pins. It was discovered that
once capacitor C17416 part # 214029 was removed the load went away. It is a
43 pf capacitor. The mystery is this capacitor did not measure leaky. It is
believed the glue that held the device in place became conductive and causes
the trouble.



Good luck

kip


  #7   Report Post  
john
 
Posts: n/a
Default Rca ctc203aa5

This was picked up from another site
some very useful info .
You will need Chipper Checker for this..

CTC203
#1

*IIC "Run" Bus Servicing Strategies
This Phrase means, I squared C
Preface

This chassis incorporates 3 two wire IIC system control buses. They are;
Standby, Run, and Gemstar. This article only addresses the Run Bus issue.
There is no reason why the same approach cannot be used to isolate troubles
in either Standby or Gemstar IIC Buses. However the Run Bus occupies far
more landscape in this chassis making it harder to analyze and isolate.

It is assumed by this writer that the technician using this information
possesses a reasonable & fundamental knowledge on usage of the Chipper
Checker, IIC bus system controlling, and logical troubleshooting skills.

The following is a strategy to help the technician troubleshoot of the "Run"
Data or Clock Bus in the new Thomson CTC203 consumer television chassis. My
findings so far have found the Thomson's Chipper Checker has helped to
diagnose several intermittent, and "Hard" failures in this chassis. Chipper
Checker is not the cure-all, Tell All instrument in the case of this IIC
problem. It was instrumental in indicating an error code of "16". This
error code indicated the Run Bus was being held to a Logic "0". The
following text and an antidote might be help tech localize and isolate the
device responsible for this condition.

The next step after using the Chipper Checker, is to measure the "Run" IIC
buses on U13101(3 & 4) at the instant the power is applied. There should be
communications sustained for at least 45 Milliseconds on each IIC bus. At
turn on there will be continuos activity on the RUN/CLK bus. These
communication signals will be 5 volts peak to peak. If you discover either
one of these are stuck low proceed with the following steps.

Some precautions before starting.....

Loose the solder wick. Please! In order for solder wick to be effective the
iron temperature must be very hot between 700~800 degrees. The practice of
using high soldering temperatures and the solder wick tends to retain too
much heat.. These high temperatures are too high and will break down the
adhesive used on the copper traces. Once the adhesive is broken down the
trace lifts off the board and then your are left with mess.

The Hakko 471 is an excellent choice for desoldering the components on this
board. Just keep the temperature between 600 ~ 625 degrees and avoid
prolonged contact to the traces. If wick must be used, use only thin stuff,
and keep it trimmed back so only fresh braid contacts the trace the needs to
be desoldered.

OK..... Here's the Strategy for Isolating Error "16"

Place a short between the Q14104(C & E) located @ Q7 of main CBA. This
turns "ON" the necessary B+ to all the peripheral IC's in the chassis. It
must be done otherwise the "Run" Data and Clock buses will be loaded down
because all of the peripheral IC's are are loading them down.
Next float U13101 (3 & 4) these are the "RUN" data and clock pins from the
U13101 CPU.
Next apply power to the set. No need to turn on the television.
Next measure the solder foils or lands where U13101 (3 & 4) were connected.
The buses are supposed to be pulled high by one external pull up resistor
R13166 and R13169 on the each line. They both lines should measure between 5
~ 5.3 volts. If not, you will need to find out why. It has been my
experience that one or the other is low. It is possible both may be low too
but if so you will probably find as common reason. I.E. cracked board, board
contamination, missing B+ to a peripheral.
Finding the load can be tricky. On two out of five occasions these lines did
not measure a low resistance to ground. Instead they measured about 13K each
using a Fluke 78 meter. But an analogue meter gave different readings on the
bad line, 3K on the bad compared to 10K on the good line. The other two
televisions had solder bridges in the tuner assembly that caused the lines
to be held to ground, and the last Television had a defective Audio MTS
decoder IC U11601. Apparently on the last chassis the Stereo decoder did not
send an acknowledgment to the CPU after the first polling of the
peripherals. Note: If this chassis does not receive a ACK from each
peripheral the set will not turn on and it will log an error relative to the
defective peripheral.
Once it has been determined which bus is low, locate jumper wires that
relate to the appropriate bus and desolder them one at a time. Always
checking the condition on the land of U13101. The best way is to attack this
problem is to "half" the circuit. This means measure one side, and break the
line somewhere in the middle of the circuit between the CPU and the
furthest point away. Obviously always monitor the line that's in trouble.
Disconnecting the jumpers will make it easier in the localize the branch &
isolation the peripheral or passive component responsible for the defect. Be
careful to limit movement the free end of these jumpers it may weaken the
foil on the soldered end and the pad will tear from the board.

Begin As soon as you see the troubled line go high (5.0 ~ 5.2) volts you
have found the branch. At this point you will need to follow the schematic
and isolate the active components i.e. F2PIP module, T-4 chip, Stereo
decoder. If all else fails then you may have a passive components. Chip
capacitors should not be ruled out as potential suspects.

Jumpers related to "Run" Data are JW13122, JW13124, JW13128, and JW12112
Jumper related to "Run" Clock are JW13120, JW13123, JW13127, **JC12103

** A "JC" is a Jumper Component. It may look like a small chip resistor with
the number "0" printed on it. Some manufactures call them zero ohm
resistors.




Example of a Logic "0" Data Bus Problem

I was recently involved in troubleshooting a model F36445 CTC203 where it
was determined the IIC bus was held to logic "0". After lifting jumper wire
JW12112 on the data line, the load on U13101 (4) climbed from 1.9 to 5.2
volts. This jumper coupled the data line to several passive components, in
the tuner and Stereo decoder circuit, along with active components U16601(
9) MTS decoder, and the U17401(19) tuner PLL controller. A decision had to
be made to cut a trace ( see silk screen) located adjacent to the tuner
shield, in order to isolate the short. If you have the Thomson ESI schematic
locate the tuner section. The short was located along the data bus that
controls the tuner PLL. Capacitor C17416 in the silk screen was the
culprit. Removing the capacitor and reconnecting the cut trace allowed the
data line to finally go high and the set was operating again.. Capacitor was
replaced wit part# 214029 a 43 pf surface mounted capacitor.




Clipped from another source..

#2

Place a jumper between Q14104(E & C) This will turn on the Switched 12
volts and apply power to the all the peripherals. Next, carefully remove the
pins of U13101(3 &4) and apply power to the set. Both traces on the data and
clock must be 5 volts. If it is 5 volts then no excessive loads on the Data
or clock lines exist. In this case U13101(3) was 1.9 volts. This indicated
that something that connected to the Data line was loading it down. All ICs
were isolated by removal of the data and clock pins. It was discovered that
once capacitor C17416 part # 214029 was removed the load went away. It is a
43 pf capacitor. The mystery is this capacitor did not measure leaky. It is
believed the glue that held the device in place became conductive and causes
the trouble.



Good luck

kip


  #8   Report Post  
john
 
Posts: n/a
Default Rca ctc203aa5

Here are a few possibles..


RCA F31317YX53

Dead , F14201 = 5 Amp Blown. Customer Said There Were Sparks Inside Tv .

Slidewire Electronics

Resolder L14401 . Replaced Q14401 H.O.T. #237470 .
Replaced Smoked Parts In Ps. Q14101 = #244223 , Q14102 = #147665 ,
Q14103 = #232218 , R14107 = 43 Ohm 1/4 W , R14109 = 750 Ohm 1/4 W .

Chassis Ctc203ad5 , Sam'S 4600 .

---------------------------------------------------------------

RCA P46810LV

Dead. Wont Power Up

Chambers Electronic Service

Replaced Defective Mosfet Q14101 (237469). Replaced Burned Resistor R14125
(241258) 36 Ohm 1/4 Watt. Replaced Defective Low Voltage Regulator U14101
(237476). Replaced Shorted Smd 3v Zener Diode Cr14108 (238099). Set Powered
Up And Worked Fine

---------------------------------------------------------------

RCA CTC203

Dead

Computer & Communication Solutions Www.Ccsinc.Com 804-642-9731

Replace Q14101 P/N 244223, & Q14103 P/N 232218 Both Should Be Done Together

---------------------------------------------------------------

RCA CTC203

Dead

Sam Oyler : Electric Medic

Replace Q14101,Q14102,Q14103,R14107 & 5 A Gma Fuse

---------------------------------------------------------------

RCA CTC203

Dead Shorts Regulator At Plug In

Bryn Mawr Tv

Cr14109 Shorted (243626) Causing Q14101 (244223) To Fail When Plugged

---------------------------------------------------------------

RCA CTC203

Dead. Blows New Q14101

Consumer Service

R14107 43 Ohm Off Gate Of Q14101 Open
Q14101 # 244223

---------------------------------------------------------------

RCA CTC203

Dead. Fuse Blown

Dash2666

F14201 Main 5 Amp Fuse, Q14101 P/N 244223, R14107 43 Ohm, Q14401 2sd2578,
R14103 1 Megohm, Q14102 Mps8599=Nte159. Resolder L14401, Connects H. Drive
To H.O.T. Base

---------------------------------------------------------------

RCA CTC203

Dead. Squealing Noise When Plugged In

Bryn Mawr Tv

Shorted Q14401 # 242224 (2sd2578) Q14101 # 244223
Open R14107 # 244214 (43 Ohm 1/4 Watt)
Give Main Cba Good Solder Up Many Poor Solder Connections

---------------------------------------------------------------

RCA CTC203

High Voltage No Go. Hums. Remove L14401 And Clean Leads To Prevent Repeat
Hot Failure



Q14101 Regulator (244223), Hot (242224), R14107 (43 Ohm),Q14102 (Mps8599)


---------------------------------------------------------------

RCA CTC203AD5

Dead

Bryn Mawr Tv

Q14101 (244223) Q14102 (147665) Q14103 (232218) R14107 (244214)
Q14401 (242224) F14210 (175425/Gma5)
Resolder L14401 Base Of Horiz Output

---------------------------------------------------------------

RCA CTC203AS

Repeat Failure Of Hot

Doug - Vision Video Labs, Inc

Power Supply Screams And Hot Shorts 2hrs After Rebuilding Power Supply For
Dead. Q14101 Drain Measured 159v. Hot Had 136v B+. Found T14301 Horz Driver
Xformer Had Changed Value. Replace Transformer (#252843) To Fix.

---------------------------------------------------------------

RCA CTC203AX

Dead

Ken Stolpman

Q14101 #244223, F14201 5a/250v, And An Open Trace At Pad On Pin 9 Of
T14101 Causing Q14101 To Short At Plug In.

kip


  #9   Report Post  
john
 
Posts: n/a
Default Rca ctc203aa5

Here are a few possibles..


RCA F31317YX53

Dead , F14201 = 5 Amp Blown. Customer Said There Were Sparks Inside Tv .

Slidewire Electronics

Resolder L14401 . Replaced Q14401 H.O.T. #237470 .
Replaced Smoked Parts In Ps. Q14101 = #244223 , Q14102 = #147665 ,
Q14103 = #232218 , R14107 = 43 Ohm 1/4 W , R14109 = 750 Ohm 1/4 W .

Chassis Ctc203ad5 , Sam'S 4600 .

---------------------------------------------------------------

RCA P46810LV

Dead. Wont Power Up

Chambers Electronic Service

Replaced Defective Mosfet Q14101 (237469). Replaced Burned Resistor R14125
(241258) 36 Ohm 1/4 Watt. Replaced Defective Low Voltage Regulator U14101
(237476). Replaced Shorted Smd 3v Zener Diode Cr14108 (238099). Set Powered
Up And Worked Fine

---------------------------------------------------------------

RCA CTC203

Dead

Computer & Communication Solutions Www.Ccsinc.Com 804-642-9731

Replace Q14101 P/N 244223, & Q14103 P/N 232218 Both Should Be Done Together

---------------------------------------------------------------

RCA CTC203

Dead

Sam Oyler : Electric Medic

Replace Q14101,Q14102,Q14103,R14107 & 5 A Gma Fuse

---------------------------------------------------------------

RCA CTC203

Dead Shorts Regulator At Plug In

Bryn Mawr Tv

Cr14109 Shorted (243626) Causing Q14101 (244223) To Fail When Plugged

---------------------------------------------------------------

RCA CTC203

Dead. Blows New Q14101

Consumer Service

R14107 43 Ohm Off Gate Of Q14101 Open
Q14101 # 244223

---------------------------------------------------------------

RCA CTC203

Dead. Fuse Blown

Dash2666

F14201 Main 5 Amp Fuse, Q14101 P/N 244223, R14107 43 Ohm, Q14401 2sd2578,
R14103 1 Megohm, Q14102 Mps8599=Nte159. Resolder L14401, Connects H. Drive
To H.O.T. Base

---------------------------------------------------------------

RCA CTC203

Dead. Squealing Noise When Plugged In

Bryn Mawr Tv

Shorted Q14401 # 242224 (2sd2578) Q14101 # 244223
Open R14107 # 244214 (43 Ohm 1/4 Watt)
Give Main Cba Good Solder Up Many Poor Solder Connections

---------------------------------------------------------------

RCA CTC203

High Voltage No Go. Hums. Remove L14401 And Clean Leads To Prevent Repeat
Hot Failure



Q14101 Regulator (244223), Hot (242224), R14107 (43 Ohm),Q14102 (Mps8599)


---------------------------------------------------------------

RCA CTC203AD5

Dead

Bryn Mawr Tv

Q14101 (244223) Q14102 (147665) Q14103 (232218) R14107 (244214)
Q14401 (242224) F14210 (175425/Gma5)
Resolder L14401 Base Of Horiz Output

---------------------------------------------------------------

RCA CTC203AS

Repeat Failure Of Hot

Doug - Vision Video Labs, Inc

Power Supply Screams And Hot Shorts 2hrs After Rebuilding Power Supply For
Dead. Q14101 Drain Measured 159v. Hot Had 136v B+. Found T14301 Horz Driver
Xformer Had Changed Value. Replace Transformer (#252843) To Fix.

---------------------------------------------------------------

RCA CTC203AX

Dead

Ken Stolpman

Q14101 #244223, F14201 5a/250v, And An Open Trace At Pad On Pin 9 Of
T14101 Causing Q14101 To Short At Plug In.

kip


  #10   Report Post  
Jason D.
 
Posts: n/a
Default Rca ctc203aa5

This set is totally dead. I did the repairs on L14101

Hi Lance,

Ah.

Power supply chirps when line cord is plugged in.


Like normal start up? Are you getting correct voltages in standby
for appox 140V B+, etc?

The 5v regulated voltage is present at all times. When the power button is
pressed the 2.5v appears on j13301 pin 18 and the 12v appears on the 12v
regulator u 14404. Both voltages disappear within a second or two and they
do not pulse they just die. Set has to be unplugged before it will respond


This is unusual, RCA designed this way to try 3 times for any reason
even x-ray shutdown. You will hear 3 clicks from relay.

Do you happen to have plug in F2PIP module in this chassis? Remove it
and try again. Sometimes this hangs the I2C data bus due to loss of
3.3V on that F2PIP regulator circuit, somewhat rare. I came across
this 3
times so far, was cracked solder joint on one SMD resistor that sets
the voltage for the LM317 regulator. But it usually causes 3 strikes
and out syptom.

with startup surge. On the collector of the horizontal output is 138v
regulated voltage.


Good!! Power supply is fine, this confirms it. Go on to other
areas.

Could this be a problem with the Gemstar module as
system control is integrated to it or do I have a data clock line problem.
I unplugged j13104 to try and isolate problen and had the same results on
the above tests.


Is it dumb or smart chassis? Smart chassis uses only one ribbon for
gemstar and can be left off. Two big ICs (jungle & micro).
Dumb chassis relies on gemstar (has two ribbons) and only one jungle
IC. The micro is part of gemstar, hence the dumb term.

Cheers,

Wizard


  #11   Report Post  
Jason D.
 
Posts: n/a
Default Rca ctc203aa5

This set is totally dead. I did the repairs on L14101

Hi Lance,

Ah.

Power supply chirps when line cord is plugged in.


Like normal start up? Are you getting correct voltages in standby
for appox 140V B+, etc?

The 5v regulated voltage is present at all times. When the power button is
pressed the 2.5v appears on j13301 pin 18 and the 12v appears on the 12v
regulator u 14404. Both voltages disappear within a second or two and they
do not pulse they just die. Set has to be unplugged before it will respond


This is unusual, RCA designed this way to try 3 times for any reason
even x-ray shutdown. You will hear 3 clicks from relay.

Do you happen to have plug in F2PIP module in this chassis? Remove it
and try again. Sometimes this hangs the I2C data bus due to loss of
3.3V on that F2PIP regulator circuit, somewhat rare. I came across
this 3
times so far, was cracked solder joint on one SMD resistor that sets
the voltage for the LM317 regulator. But it usually causes 3 strikes
and out syptom.

with startup surge. On the collector of the horizontal output is 138v
regulated voltage.


Good!! Power supply is fine, this confirms it. Go on to other
areas.

Could this be a problem with the Gemstar module as
system control is integrated to it or do I have a data clock line problem.
I unplugged j13104 to try and isolate problen and had the same results on
the above tests.


Is it dumb or smart chassis? Smart chassis uses only one ribbon for
gemstar and can be left off. Two big ICs (jungle & micro).
Dumb chassis relies on gemstar (has two ribbons) and only one jungle
IC. The micro is part of gemstar, hence the dumb term.

Cheers,

Wizard
  #12   Report Post  
Lance Dyer
 
Posts: n/a
Default Rca ctc203aa5

Hi Jason:


Do you happen to have plug in F2PIP module in this chassis? Remove it
and try again. Sometimes this hangs the I2C data bus due to loss of
3.3V on that F2PIP regulator circuit, somewhat rare. I came across
this 3
times so far, was cracked solder joint on one SMD resistor that sets
the voltage for the LM317 regulator. But it usually causes 3 strikes
and out syptom.



There is no pip in this set

Is it dumb or smart chassis? Smart chassis uses only one ribbon for
gemstar and can be left off. Two big ICs (jungle & micro).
Dumb chassis relies on gemstar (has two ribbons) and only one jungle
IC. The micro is part of gemstar, hence the dumb term.

this set has the two ribbons from the gemstar module


This is unusual, RCA designed this way to try 3 times for any reason
even x-ray shutdown. You will hear 3 clicks from relay.



when the power button is pushed there is no click of the relay




Cheers,

Wizard



  #13   Report Post  
Lance Dyer
 
Posts: n/a
Default Rca ctc203aa5

Hi Jason:


Do you happen to have plug in F2PIP module in this chassis? Remove it
and try again. Sometimes this hangs the I2C data bus due to loss of
3.3V on that F2PIP regulator circuit, somewhat rare. I came across
this 3
times so far, was cracked solder joint on one SMD resistor that sets
the voltage for the LM317 regulator. But it usually causes 3 strikes
and out syptom.



There is no pip in this set

Is it dumb or smart chassis? Smart chassis uses only one ribbon for
gemstar and can be left off. Two big ICs (jungle & micro).
Dumb chassis relies on gemstar (has two ribbons) and only one jungle
IC. The micro is part of gemstar, hence the dumb term.

this set has the two ribbons from the gemstar module


This is unusual, RCA designed this way to try 3 times for any reason
even x-ray shutdown. You will hear 3 clicks from relay.



when the power button is pushed there is no click of the relay




Cheers,

Wizard



  #14   Report Post  
Jason D.
 
Posts: n/a
Default Rca ctc203aa5

On Fri, 9 Apr 2004 09:06:34 -0600, "Lance Dyer"
wrote:

Hi Jason:

times so far, was cracked solder joint on one SMD resistor that sets
the voltage for the LM317 regulator. But it usually causes 3 strikes
and out syptom.



There is no pip in this set


Okay,


Is it dumb or smart chassis? Smart chassis uses only one ribbon for
gemstar and can be left off. Two big ICs (jungle & micro).
Dumb chassis relies on gemstar (has two ribbons) and only one jungle
IC. The micro is part of gemstar, hence the dumb term.

this set has the two ribbons from the gemstar module


This is dumb chassis. The micro IS in the gemstar module, gemstar
module costs about 100. Ouch!! Gemstar module must have both ribbons
correctly plugged in.

Really check carefully that you have standby power to the gemstar, the
gemstar's eeprom IC is on the mainboard. Is it getting 5V? And did
I2C bus talk for short time when tv plugged in, also did I2C talk when
remote and buttons are pressed?

Also double check that I2C buses aren't shorted or open along the
tracks.


when the power button is pushed there is no click of the relay


No response to remote either?

The middle two of 4 pins female connector is I2C bus for the A/V
board, I think. Should be labeled on the solder side of chassis.
This I2C also is strung along to the tuner's two pins.

Sometimes I see cracked traces.

Cheers,

Wizard
  #15   Report Post  
Jason D.
 
Posts: n/a
Default Rca ctc203aa5

On Fri, 9 Apr 2004 09:06:34 -0600, "Lance Dyer"
wrote:

Hi Jason:

times so far, was cracked solder joint on one SMD resistor that sets
the voltage for the LM317 regulator. But it usually causes 3 strikes
and out syptom.



There is no pip in this set


Okay,


Is it dumb or smart chassis? Smart chassis uses only one ribbon for
gemstar and can be left off. Two big ICs (jungle & micro).
Dumb chassis relies on gemstar (has two ribbons) and only one jungle
IC. The micro is part of gemstar, hence the dumb term.

this set has the two ribbons from the gemstar module


This is dumb chassis. The micro IS in the gemstar module, gemstar
module costs about 100. Ouch!! Gemstar module must have both ribbons
correctly plugged in.

Really check carefully that you have standby power to the gemstar, the
gemstar's eeprom IC is on the mainboard. Is it getting 5V? And did
I2C bus talk for short time when tv plugged in, also did I2C talk when
remote and buttons are pressed?

Also double check that I2C buses aren't shorted or open along the
tracks.


when the power button is pushed there is no click of the relay


No response to remote either?

The middle two of 4 pins female connector is I2C bus for the A/V
board, I think. Should be labeled on the solder side of chassis.
This I2C also is strung along to the tuner's two pins.

Sometimes I see cracked traces.

Cheers,

Wizard
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