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From: Airioch on 6 Oct 2006 09:48
In article <1160109286.411142.297540(a)m7g2000cwm.googlegroups.com>,
stratus46(a)yahoo.com says...

> test(a)test.com wrote:
> > Recently got a sony PVM-1954Q that had some bad electrolytics in
> > it.
> >
> > I recapped the A board, (132 caps, I won't be doing that anytime
> > soon again) fired it up and did the alignments according to the
> > service manual (I have that as well).
> >
> > The only issue that 'remains' is there are 3 lines, one each for
> > the red, blue, and green guns at the very top of the picture.
> > This is evident in all modes, 4:3, 16:9, and underscan. You cant
> > 'see' it in 4:3 mode as it's at the very top of the display but
> > it's there if you move the picture with the vertical centering.
> >
> > Wave forms and voltages look normal on IC506, 502, Q507 and Q505.
> >
> > Picture looks good. All other alignments appear to work correctly.
> >
> > Just can't get rid of those retrace lines. They look abnormal when
> > you use the 16:9 or underscan modes.
> >
> > Anyone ever run across anything like this ?
>
> Firts thing, you went WAY overboard on the caps thing. As others said,
> C572 and C584 are the most common bad ones. There are a couple others I
> check in the sweep area, C588, C590 and a few others. Get an ESR meter
> and you'll save scads of time.

I'll have to get an ESR meter ( I don't normally work on monitors for
folks..), always good to have tools laying about when you need them.


Checked all the component values in the vertical drive area. All of them
are well within tolerance. C576,584,587,588,589,590,591,586 (I've
replaced all the electrolytics but pulled the ones in the section and
checked them anyway..) All the resistors R1515,1522,1523,1527,1528,1531
all check out as well, almost spot on the value as stated on the
schematic and in the parts list. Q513 and 515 appear to be okay as well,
I've getting a pretty close hfe reading on both of them, 157 I believe
was the figure, no leakage.
>
> Your 'retrace' lines are not retrace lines. Those are the beam current
> feedback measurements and if you get rid of them, it will look
> terrible. In NTSC they fall on lines 17,18,19 - RGB respectively. You
> measure TP403 with a scope and set G2 until the lowest value of those 3
> lines is +1.35 volts.

Looked at that, I'm coming up with 1.35 as measured on the lowest of the
set, tried dropping it lower, still see the aforementioned lines.

Are you indicating that those lines are supposed to be there and visible
? (I've never seen this monitor or one like it run before so this is new
to me... I'm just going by what the owner was indicating, "one day they
were not there, now they are.." )

> Do you have the service manual? It explains most of this though the
> schematics are drawn poorly.

If you can call it a service manual, yes, I have it. Test points not
labeled or not listed, signals present on the test points not indicated,
heck I think I've only found one or two of them on the schematic itself.

The G2 alignment, I kept looking for the Screen VR reference, ahhhh,
look at the S board, look at the CRT, look, G2 and it's associated
adjustment. Pretty poorly put together.

All the components I've checked are within 5% of specified values, even
the ceramic disc caps are within 10%.

I appreciate the responses.

airi--

From: stratus46 on 6 Oct 2006 12:20
Airioch wrote:
> In article <1160109286.411142.297540(a)m7g2000cwm.googlegroups.com>,
> stratus46(a)yahoo.com says...
>
<snip>
> > First thing, you went WAY overboard on the caps thing. As others
said,
> > C572 and C584 are the most common bad ones. There are a couple
others I
> > check in the sweep area, C588, C590 and a few others. Get an ESR
meter
> > and you'll save scads of time.
>
> I'll have to get an ESR meter ( I don't normally work on monitors
for
> folks..), always good to have tools laying about when you need them.
>
>
> Checked all the component values in the vertical drive area. All of
them
> are well within tolerance. C576,584,587,588,589,590,591,586 (I've
> replaced all the electrolytics but pulled the ones in the section
and
> checked them anyway..) All the resistors
R1515,1522,1523,1527,1528,1531
> all check out as well, almost spot on the value as stated on the
> schematic and in the parts list. Q513 and 515 appear to be okay as
well,
> I've getting a pretty close hfe reading on both of them, 157 I
believe
> was the figure, no leakage.
> >
> > Your 'retrace' lines are not retrace lines. Those are the beam
current
> > feedback measurements and if you get rid of them, it will look
> > terrible. In NTSC they fall on lines 17,18,19 - RGB respectively.
You
> > measure TP403 with a scope and set G2 until the lowest value of
those 3
> > lines is +1.35 volts.
>
> Looked at that, I'm coming up with 1.35 as measured on the lowest of the
> set, tried dropping it lower, still see the aforementioned lines.
>
> Are you indicating that those lines are supposed to be there and visible
> ? (I've never seen this monitor or one like it run before so this is new
> to me... I'm just going by what the owner was indicating, "one day they
> were not there, now they are.." )
>
> > Do you have the service manual? It explains most of this though the
> > schematics are drawn poorly.
>
> If you can call it a service manual, yes, I have it. Test points not
> labeled or not listed, signals present on the test points not indicated,
> heck I think I've only found one or two of them on the schematic itself.
>
> The G2 alignment, I kept looking for the Screen VR reference, ahhhh,
> look at the S board, look at the CRT, look, G2 and it's associated
> adjustment. Pretty poorly put together.
>
> All the components I've checked are within 5% of specified values, even
> the ceramic disc caps are within 10%.
>
> I appreciate the responses.
>
> airi--
I just looked at 1354 at my bench. The call lines are only visible in
underscan regardless of pulse cross.

GG

From: Airioch on 6 Oct 2006 12:40
In article <1160151644.392889.146640(a)i42g2000cwa.googlegroups.com>,
stratus46(a)yahoo.com says...

<snip..>

> I just looked at 1354 at my bench. The call lines are only visible in
> underscan regardless of pulse cross.
>
Hmmm, I see them in underscan and 16:9 modes on the 1954, 4:3 of course
they are at the top out of visible sight.

The main reason I'm 'worried' about them is I was told one day they
weren't.

They were visible in 4:3 until I replaced the Electrolytics, there was a
slight vertical foldover and the caps fixed that (well one of them did).

again, I appreciate the response.

Recommend any good ESR testers ?

airi--
From: stratus46 on 6 Oct 2006 15:32
Airioch wrote:
> In article <1160151644.392889.146640(a)i42g2000cwa.googlegroups.com>,
> stratus46(a)yahoo.com says...
>
> <snip..>
>
> > I just looked at 1354 at my bench. The call lines are only visible
in
> > underscan regardless of pulse cross.
> >
> Hmmm, I see them in underscan and 16:9 modes on the 1954, 4:3 of
course
> they are at the top out of visible sight.
>
> The main reason I'm 'worried' about them is I was told one day they
> weren't.
>
> They were visible in 4:3 until I replaced the Electrolytics, there
was a
> slight vertical foldover and the caps fixed that (well one of them
did).
>
> again, I appreciate the response.
>
> Recommend any good ESR testers ?
>
> airi--

You're right on the 16:9 mode. I rarely use it so I forgot.

We use the 'Capacitor Wizard' which works very well but I heard it was
no longer available. Check threads on ESR meters. There is a lot of
info on this.

GG

From: stratus46 on 6 Oct 2006 15:38
Airioch wrote:
> In article <1160151644.392889.146640(a)i42g2000cwa.googlegroups.com>,
> stratus46(a)yahoo.com says...
>
> <snip..>
>
> > I just looked at 1354 at my bench. The call lines are only visible in
> > underscan regardless of pulse cross.
> >
> Hmmm, I see them in underscan and 16:9 modes on the 1954, 4:3 of
course
> they are at the top out of visible sight.
>
> The main reason I'm 'worried' about them is I was told one day they
> weren't.
>
> They were visible in 4:3 until I replaced the Electrolytics, there
was a
> slight vertical foldover and the caps fixed that (well one of them
did).
>
> again, I appreciate the response.
>
> Recommend any good ESR testers ?
>
> airi--

BTW I also forgot that those cal lines were always there so if you have
ops saying otherwise, they just didn't notice. I call it the dripping
faucet syndrome. It's REAL hard to go back to not hearing the drip.

The Sony broadcast BVM series also does beam feedback and has those
lines at the start of V sweep. If colorists can get over it, EVERYBODY
can because those folks are the most demanding group there is.

GG

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