Magnavox CCR190AT03 (Funai)

[Michael Fiedler]

I am working on a 19" Magnavox TV/VCR combination. At first the set
would shut off as soon as it turned on. I replaced a number of bad
capacitors (ESR) and then the set had a high pitched oscillation and
no picture. I then found that the HOT was shorted, so I replaced it.
When I first turned the TV on after replacing it, the picture was
extremely bright, and then it went into broken dashed oscillations
across all of the scan lines; then the picture went black. I had
sound throughout this process. The HOT is still good, but the voltage
reading is 176 volts, which I believe, is shutting down the High
Voltage. Since I am working without a schematic, I am kind of flying
blind. I do believe the flyback is good. I have seen a couple of
other posts on these beasts. Can anyone out there provide me with
potential things to look at and/or voltage readings to check? Or
maybe someone has seen the same problem and has THE solution?
Thanks in advance for any help.

Mike

 

[Jerry G.]

The G2 voltage from the flyback assy may be too high, there may be a high
voltage regulation fault, or the CRT may be shorted, and or the flyback assy
may also require replacement. It is possible that there is other damage as
well, and the new HOT may be also damaged again when this happens.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
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I am working on a 19" Magnavox TV/VCR combination. At first the set
would shut off as soon as it turned on. I replaced a number of bad
capacitors (ESR) and then the set had a high pitched oscillation and
no picture. I then found that the HOT was shorted, so I replaced it.
When I first turned the TV on after replacing it, the picture was
extremely bright, and then it went into broken dashed oscillations
across all of the scan lines; then the picture went black. I had
sound throughout this process. The HOT is still good, but the voltage
reading is 176 volts, which I believe, is shutting down the High
Voltage. Since I am working without a schematic, I am kind of flying
blind. I do believe the flyback is good. I have seen a couple of
other posts on these beasts. Can anyone out there provide me with
potential things to look at and/or voltage readings to check? Or
maybe someone has seen the same problem and has THE solution?
Thanks in advance for any help.

Mike

 

[Ol' Duffer]

The HOT is still good, but the voltage reading is 176 volts,
which I believe, is shutting down the High Voltage.

IIRC, the voltage should be around 114, so it sounds like
the supply has lost its feedback path, and is running solely
on current limit. If so, it won't last long. I think the
last one of these I had to chase down turned out to be a
shorted little glass diode, but it could be any one of a
number of parts in the regulation loop.