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From: Meatman on 9 Jul 2010 02:34
32" RCA Entertainment Series CRT. Had popping noise w/ no pic or
sound. Replaced HOT and FBT. Now A-OK except: At start-up, every start-
up, contrast/brightness is way low/very dark picture. After 3-5 secs
it corrects and is normal. I even let it run for 30 hrs straight to
see if it would freak-out in other ways. It didn't. Problem is quite
sufferable, but I'd like to chase it down. Ideas? Thanks again!
From: Arfa Daily on 9 Jul 2010 04:43


"Meatman" <KevinLee33(a)comcast.net> wrote in message
news:6f199bd8-ac89-41ee-a6e0-6aae02e397cd(a)y11g2000yqm.googlegroups.com...
> 32" RCA Entertainment Series CRT. Had popping noise w/ no pic or
> sound. Replaced HOT and FBT. Now A-OK except: At start-up, every start-
> up, contrast/brightness is way low/very dark picture. After 3-5 secs
> it corrects and is normal. I even let it run for 30 hrs straight to
> see if it would freak-out in other ways. It didn't. Problem is quite
> sufferable, but I'd like to chase it down. Ideas? Thanks again!

Wrongly set 'screen' control on your new FBT ? Taking a while for the beam
limiter to assess what's going on and correct for it ? If original FBT was
faulty, beam limiter sense resistor in ground return gone high ?

Arfa

From: Meatman on 10 Jul 2010 02:37
On Jul 9, 3:43 am, "Arfa Daily" <arfa.da...(a)ntlworld.com> wrote:
> "Meatman" <KevinLe...(a)comcast.net> wrote in message
>
> news:6f199bd8-ac89-41ee-a6e0-6aae02e397cd(a)y11g2000yqm.googlegroups.com...
>
> > 32" RCA Entertainment Series CRT. Had popping noise w/ no pic or
> > sound. Replaced HOT and FBT. Now A-OK except: At start-up, every start-
> > up, contrast/brightness is way low/very dark picture. After 3-5 secs
> > it corrects and is normal. I even let it run for 30 hrs straight to
> > see if it would freak-out in other ways. It didn't. Problem is quite
> > sufferable, but I'd like to chase it down. Ideas? Thanks again!
>
> Wrongly set 'screen' control on your new FBT ? Taking a while for the beam
> limiter to assess what's going on and correct for it ? If original FBT was
> faulty, beam limiter sense resistor in ground return gone high ?
>
> Arfa

BTW: RCA MODEL F32450 CHASSIS: ATC113CA1

I just dialed in the FBT by eyeball with it turned on. Tweaked both
settings til I had what I thought was best picture. Then adjusted
from menu settings. Should it be done another way? Everything else
is kosher except for prob described. THX!!!
From: Meatman on 10 Jul 2010 02:45
<<
beam limiter sense resistor in ground return gone high ? >>

And where would I locate this little beast...approximately?
From: Arfa Daily on 10 Jul 2010 04:49


"Meatman" <KevinLee33(a)comcast.net> wrote in message
news:3fd25b30-022b-48ff-87c6-4499945051d6(a)u7g2000yqm.googlegroups.com...
> <<
> beam limiter sense resistor in ground return gone high ? >>
>
> And where would I locate this little beast...approximately?

The setting of the screen control can be very critical, depending on the
circuitry design, and the condition of the CRT. Usually, there is a point to
measure a voltage on, and a critical voltage to set on that point, using the
control. A service manual will usually be helpful for that. The beam current
sense resistor, assuming that it has one in the position I indicated, is
usually physically quite close to the FBT itself.

Please note though that the observations I am making are general to CRT TV
sets from the last 20 years, and not necessarily specific to your make and
model, which I am not intimately familiar with, it being a U.S. model, and
my practical experience all being with U.K. models. However, that said, the
circuitry design from what I've seen, is generally pretty similar in all but
the front-end low level signal and colour processing circuitry.

Arfa

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