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From: kjlawren01 on 11 Oct 2008 18:24
A challenge indeed......

What's known good: Each of the three projectors (red, green, blue) are
fully operable and in focus. Audio is unaffected and functions well.

The symptom is akin to the effect viewed as a partial signal block from HBO
in the late 1970's. where the picture shows up on screen with a wavy
horizontal flickering side to side motion. Depending upon the input signal
strength, the horizontal wavering strengthens as the signal gets stronger.

When using an antenna ( tested both antenna 1 input and antenna 2 input),
Channel 8 can receive marginal reception as the the channel is broadcasted
from 45 miles away. Some snow (weak signal indication), a little spotty
(microwave background distortion), but very few wavering lines as compared
to viewing a VCR/DVD input. All other channels are too distant to receive (I
have not activated cable TV yet). On channels without formatted broadcasted
signal received ( snow microwaves only), there is no indication of wavering
lines at all, and no indication of a malfunction.

With the input coming from either video 1 or video 2 (front and back tested)
having an 8mm camera connected to the TV, and active, and panning the lense
to the kitchen (not so bright), horizontal distortion exists. Then when
panning the 8mm camera to view through the window outside in the bright
sunlight, the distortion intensifies and the video output on the TV screen
becomes unrecognizable.

Without any signal input showing up on the screen, in the case of the full
screen TV setup menus, all text colors and text are sharp and background
color is picture prefect. This is also the case when the vhs is connected
and the stop button is pressed) with a tape active but not playing. The
output is the pretty blue blank screen (normal attribute in this scenario)
and the display statistics (date, time, position counter) appear in picture
perfectly clear white lettering.

If you have any TV experiences / thoughts to share (however
trivial they may appear), I'd appreciate your input.

Many Thanks,
Ken

kjlawren01(a)earthlink.net



From: Franc Zabkar on 11 Oct 2008 21:39
On Sat, 11 Oct 2008 16:24:09 -0600, <kjlawren01(a)earthlink.net> put
finger to keyboard and composed:

>The symptom is akin to the effect viewed as a partial signal block from HBO
>in the late 1970's. where the picture shows up on screen with a wavy
>horizontal flickering side to side motion. Depending upon the input signal
>strength, the horizontal wavering strengthens as the signal gets stronger.

Your set uses the VZ1 chassis.

Maybe the following repair tip applies to you.

Projection Repair Tips (page 2):
http://124.106.125.72/tv%20vcr%20repair%20tips/project02.htm

Mitsubishi model VS40VA2 chassis VZ1

Symptom:
Washed out video - dark picture with bending and tearing - looks like
AGC problem but problem is also on video input

Fix:
Check/replace C7001 (4.7uf @ 35v), C7011 & C7027 (2.2uf @ 35v)

BTW, I ignored your first post because (1) its size flagged it as
spam, and (2) it was posted to the wrong group. And now you have
reposted this message twice to the same group.

Here's a friendly tip. Take some time to acquaint yourself with
Netiquette as it applies to Usenet. You will get a much better
response to your questions if you do.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
From: Leonard Caillouet on 11 Oct 2008 22:03
<kjlawren01(a)earthlink.net> wrote in message
news:b5idnY74gtyChGzVnZ2dnUVZ_gCdnZ2d(a)earthlink.com...
>A challenge indeed......
>
> What's known good: Each of the three projectors (red, green, blue) are
> fully operable and in focus. Audio is unaffected and functions well.
>
> The symptom is akin to the effect viewed as a partial signal block from
> HBO
> in the late 1970's. where the picture shows up on screen with a wavy
> horizontal flickering side to side motion. Depending upon the input signal
> strength, the horizontal wavering strengthens as the signal gets stronger.
>
> When using an antenna ( tested both antenna 1 input and antenna 2 input),
> Channel 8 can receive marginal reception as the the channel is broadcasted
> from 45 miles away. Some snow (weak signal indication), a little spotty
> (microwave background distortion), but very few wavering lines as compared
> to viewing a VCR/DVD input. All other channels are too distant to receive
> (I
> have not activated cable TV yet). On channels without formatted
> broadcasted
> signal received ( snow microwaves only), there is no indication of
> wavering
> lines at all, and no indication of a malfunction.
>
> With the input coming from either video 1 or video 2 (front and back
> tested)
> having an 8mm camera connected to the TV, and active, and panning the
> lense
> to the kitchen (not so bright), horizontal distortion exists. Then when
> panning the 8mm camera to view through the window outside in the bright
> sunlight, the distortion intensifies and the video output on the TV screen
> becomes unrecognizable.
>
> Without any signal input showing up on the screen, in the case of the
> full
> screen TV setup menus, all text colors and text are sharp and background
> color is picture prefect. This is also the case when the vhs is connected
> and the stop button is pressed) with a tape active but not playing. The
> output is the pretty blue blank screen (normal attribute in this scenario)
> and the display statistics (date, time, position counter) appear in
> picture
> perfectly clear white lettering.
>
> If you have any TV experiences / thoughts to share (however
> trivial they may appear), I'd appreciate your input.
>
> Many Thanks,
> Ken
>
> kjlawren01(a)earthlink.net
>
>
>


Search for info on the PIP bypass for this set. You have leaky caps on the
PIP module.

Leonard

From: kjlawren01 on 12 Oct 2008 22:17
Leonard, Thanks. You are dead on... "Search for info on the PIP bypass for
this set. You have leaky caps on the PIP module".-- the caps WERE leaking.
I used 91% isopropyl alcohol and a firm new 1" paint brush and cleaned off
of the entire PIP (930B552). Then, I put the PIP on my car dashboard in the
warm Sun for 2 hours before continuing. I made JPS's of every step I've
taken and am willing to send the pre-snot and post snot pics, and or all
other boards to anyone who requests analyzing them.

On the PIP, under the shield, I adjusted LO7102 & LO7101 (blk) clockwise to
where they stopped. I also flirted with VR7002 & VR7001 (blu) and acquired
some improvement, but not much. Each time, I unplugged 110v, took the PIP
board out, adjusted, reseated, replugged 100v., and re-powered on to view.
Could I flirt with adjusting them while live?

What about rotational adjustments on the main board? Any advise?

Leonard, Here a current list of specs I've been able to match up:

brand ---------------------- Mitsubishi
model ---------------------- VS-45VA1
base manual ---------------- VS-45VA2
chassis---------------------- VZ1
year------------------------- 1992
service adjust code-option--- 008
service adjust code-video pip 007
convergence adjust code ---- 009
Line = 83MI
Item (OEM) Description
========== ==============
935D162002 Side PCC
935D157001 Display
935D156001 Control Board
935D155001 PreAmp
935D154001 Front Board
935D153001 FS
935D152002 Terminal Board
935C442002 PCC
935C441002 Signal Board
935C440001 CRT Assy.
935C439001 Power Sub
935C438002 Convergence Board
935C437002 Main Board
930B552001 PIP

I do not understand these terminologies or the implications "service adjust
code option 008", "service adjust code video pip 007" , "convergence adjust
code 009", and "Line = 83MI". I've spent the day scouring the net for part
affiliation, and am looking for more insight.

Meat Plow, you say "You could always shotgun it by replacing the entire
video processing circuitry if you can determine where it is and find a
refurbed sub." Thanks Meat Plow, It's sounds like something I might
ultimately consider, but I'm not sure what "shotgun" and refurb "sub" means
(power sub?) .

Thanks Franc. What is "AGC"? Automatic gain control ??? if it is what do I
look for ? Is it replaceable, or is it possible to bypass also? Or should I
rule it out until the PIP issue is resolved?

Leonard, I may very well attempt a PIP bypass (if not replacemet). I found
web documentation for a potential bypass at the main board PIP blue
connector "GE", pinout 5(+) to 11, and 7(+) to 9, 2 - 4.7 @ 50 volts. HELP
on this!!! What does " 2 - 4.7" mean??? ... The pic is located at
http://members.aol.com/philselectronics/images/pipby.jpg

Thanks for your guidance,
Ken
kjlawren01(a)earthlink.net



"Leonard Caillouet" <nospam(a)noway.com> wrote in message
news:rWcIk.2436$XU6.1366(a)newsfe02.iad...
> Search for info on the PIP bypass for this set. You have leaky caps on
the
> PIP module.
>
> Leonard
>


From: Leonard Caillouet on 12 Oct 2008 21:24
<kjlawren01(a)earthlink.net> wrote in message
news:mYCdnSgOas7xPG_VnZ2dnUVZ_t3inZ2d(a)earthlink.com...
> Leonard, Thanks. You are dead on... "Search for info on the PIP bypass for
> this set. You have leaky caps on the PIP module".-- the caps WERE
> leaking.
> I used 91% isopropyl alcohol and a firm new 1" paint brush and cleaned off
> of the entire PIP (930B552). Then, I put the PIP on my car dashboard in
> the
> warm Sun for 2 hours before continuing. I made JPS's of every step I've
> taken and am willing to send the pre-snot and post snot pics, and or all
> other boards to anyone who requests analyzing them.
>
> On the PIP, under the shield, I adjusted LO7102 & LO7101 (blk) clockwise
> to
> where they stopped. I also flirted with VR7002 & VR7001 (blu) and acquired
> some improvement, but not much. Each time, I unplugged 110v, took the PIP
> board out, adjusted, reseated, replugged 100v., and re-powered on to view.
> Could I flirt with adjusting them while live?
>
> What about rotational adjustments on the main board? Any advise?
>
> Leonard, Here a current list of specs I've been able to match up:
>
> brand ---------------------- Mitsubishi
> model ---------------------- VS-45VA1
> base manual ---------------- VS-45VA2
> chassis---------------------- VZ1
> year------------------------- 1992
> service adjust code-option--- 008
> service adjust code-video pip 007
> convergence adjust code ---- 009
> Line = 83MI
> Item (OEM) Description
> ========== ==============
> 935D162002 Side PCC
> 935D157001 Display
> 935D156001 Control Board
> 935D155001 PreAmp
> 935D154001 Front Board
> 935D153001 FS
> 935D152002 Terminal Board
> 935C442002 PCC
> 935C441002 Signal Board
> 935C440001 CRT Assy.
> 935C439001 Power Sub
> 935C438002 Convergence Board
> 935C437002 Main Board
> 930B552001 PIP
>
> I do not understand these terminologies or the implications "service
> adjust
> code option 008", "service adjust code video pip 007" , "convergence
> adjust
> code 009", and "Line = 83MI". I've spent the day scouring the net for part
> affiliation, and am looking for more insight.
>
> Meat Plow, you say "You could always shotgun it by replacing the entire
> video processing circuitry if you can determine where it is and find a
> refurbed sub." Thanks Meat Plow, It's sounds like something I might
> ultimately consider, but I'm not sure what "shotgun" and refurb "sub"
> means
> (power sub?) .
>
> Thanks Franc. What is "AGC"? Automatic gain control ??? if it is what do I
> look for ? Is it replaceable, or is it possible to bypass also? Or should
> I
> rule it out until the PIP issue is resolved?
>
> Leonard, I may very well attempt a PIP bypass (if not replacemet). I found
> web documentation for a potential bypass at the main board PIP blue
> connector "GE", pinout 5(+) to 11, and 7(+) to 9, 2 - 4.7 @ 50 volts. HELP
> on this!!! What does " 2 - 4.7" mean??? ... The pic is located at
> http://members.aol.com/philselectronics/images/pipby.jpg
>
> Thanks for your guidance,
> Ken
> kjlawren01(a)earthlink.net
>
>
>
> "Leonard Caillouet" <nospam(a)noway.com> wrote in message
> news:rWcIk.2436$XU6.1366(a)newsfe02.iad...
>> Search for info on the PIP bypass for this set. You have leaky caps on
> the
>> PIP module.
>>
>> Leonard
>>
>
>

Just bypass the PIP module. Two caps and you are done.

Leonard

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