First of all, I'm new here and I have to tell you experienced folks my knowledge of household and automotive electronics is pretty darn good but with these newfangled electronics, it's what you'd call rather limited. You know, as in the tube technology stuff my dad taught me. Now that you folks have all had a good laugh, I need some post stone age experience.

I have a Sanyo DS31580 tv that took ill. It starts up but the picture immediately flashes approximately two times a second which is accompanied by a snapping sound through the audio. I don't think this is "motorboating", or at least it doesn't sound like the motorboating of old tube type receivers. Yeah, I know, another laugh. The volume of the snapping sound is in direct relation to how high you have the sound turned up. After running a bit I can hear the flyback transformer whine for a bit and then quiet down. After several minutes of operation, the flashing and snapping increases in tempo to approximately four times a second. I've removed the little circuit board on the back of picture tube and the snapping sound continues, so I don't the tube has fizzled out. I can't see any visible signs of burnt components or arcing on the board or flyback transformer and the whole works has suprisingly little dust. My profound ignorance makes me think it's a high voltage problem but I leave that up to your more experienced minds. I know you can use refrigerants to cool down individual components to see if they're running hot and would that be applicable here? Since the flashing increases in speed, foolishness leads me to believe something is getting warmed up but don't ask me what. Maybe it's just my frustration at my ignorance that's warming things up.

Any of you good folks out there have any suggestions as to what to check and how to check it? Remember now, you might describe what these components look like because I still have a box of resistors that are as big as a cigarrette butt and not these little gnat sized jobs. I really hate to pay some guy $60 just to bring the set into his shop and let it collect dust for months while he uses it for a table eat his lunch off of. I think they must charge storage on them also........ The other thing is there's very little I can't do other than sing or swim and I hate to be foiled by some dinky little Chinese made "thing". Thanks in advance!

The Hawk said..........

I really hate to pay some guy $60 just to bring the set into his shop and
let it
collect dust for months while he uses it for a table eat his lunch off
of.

You reall have a problem go buy a New TV.

john

"studebaker hawk" wrote in message

kip wrote:

The Hawk said..........

I really hate to pay some guy $60 just to bring the set into his shop and
let it
collect dust for months while he uses it for a table eat his lunch off
of.

You reall have a problem go buy a New TV.

john

"studebaker hawk" wrote in message


sounds like the ever famous Sanyo flyback interal leak in the focus
block section

"David Naylor" wrote in message
. ..

sounds like the ever famous Sanyo flyback interal leak in the focus block
section

Is it the focus block or the flyback?

studebaker hawk wrote in
:

I have a Sanyo DS31580 tv that took ill. It starts up but the picture
immediately flashes approximately two times a second which is
accompanied by a snapping sound through the audio.

With the back panel off the set, turn out the lights at night and turn the
tv on. Best way to see any sparks.... anywhere. Just keep your body parts
away from the high voltage.

studebaker hawk wrote:
First of all, I'm new here and I have to tell you experienced folks my
knowledge of household and automotive electronics is pretty darn good
but with these newfangled electronics, it's what you'd call rather
limited. You know, as in the tube technology stuff my dad taught me.
Now that you folks have all had a good laugh, I need some post stone
age experience.

I have a Sanyo DS31580 tv that took ill. It starts up but the picture
immediately flashes approximately two times a second which is
accompanied by a snapping sound through the audio. I don't think this
is "motorboating", or at least it doesn't sound like the motorboating
of old tube type receivers. Yeah, I know, another laugh. The volume
of the snapping sound is in direct relation to how high you have the
sound turned up. After running a bit I can hear the flyback
transformer whine for a bit and then quiet down. After several minutes
of operation, the flashing and snapping increases in tempo to
approximately four times a second. I've removed the little circuit
board on the back of picture tube and the snapping sound continues, so
I don't the tube has fizzled out. I can't see any visible signs of
burnt components or arcing on the board or flyback transformer and the
whole works has suprisingly little dust. My profound ignorance makes
me think it's a high voltage problem but I leave that up to your more
experienced minds. I know you can use refrigerants to cool down
individual components to see if they're running hot and would that be
applicable here? Since the flashing increases in speed, foolishness
leads me to believe something is getting warmed up but don't ask me
what. Maybe it's just my frustration at my ignorance that's warming
things up.

Any of you good folks out there have any suggestions as to what to
check and how to check it? Remember now, you might describe what these
components look like because I still have a box of resistors that are as
big as a cigarrette butt and not these little gnat sized jobs. I really
hate to pay some guy $60 just to bring the set into his shop and let it
collect dust for months while he uses it for a table eat his lunch off
of. I think they must charge storage on them also........ The other
thing is there's very little I can't do other than sing or swim and I
hate to be foiled by some dinky little Chinese made "thing". Thanks in
advance!






I fixed a Sony with this problem, it was arcing within the focus block
on the flyback.

Homer J Simpson wrote:
"David Naylor" wrote in message
. ..


sounds like the ever famous Sanyo flyback interal leak in the focus block
section


Is it the focus block or the flyback?





The focus block is part of the flyback on most sets.

I tried the turn the lights out and cover up the picture tube trick last night but saw no external arcing. A couple of the kids ran into the wall in the darkness, but no external arcing seen. I've seen the focus block, so is it a seperate replaceable component or part of it the flyback? Do I need to replace the whole flyback transformer?

Thanks guys, I really appreciate your expertise in this manner!
john

Homer J Simpson wrote:
"David Naylor" wrote in message
. ..


sounds like the ever famous Sanyo flyback interal leak in the focus block
section


Is it the focus block or the flyback?



Yeh the focus block is part of the fly back part is about 14 dollars

Well folks, I'm back.... I ordered a new flyback, got it yesterday, installed it last night and no more snaps or flashes, in fact, I have no picture or sound at all!!! If I turn the screen knob all the way up I can get a horizontal line across the screen and with the focus knob I can make it fat and blurry or narrow and sharp for all the good that does. I can hear the set click on when turned on, the filiments in the neck of the tube will get orange although I don't believe at bright as before, I can feel some static electricity on the outside of the tube, but no illumination whatsoever and no sound at all through the audio regardless of whether I have a signal or not.

After I got the old flyback removed, I cleaned the excess solder out of the holes in the circuit board so I could place the new one, soldered the connections on the back and replaced all the wires from where they came from (I drew a diagram beforehand). Anyone have any ideas? My solder joints all look good. I figured I'd better steer clear of the Sanyo flybacks so to be on the safe side, I got an ACME brand with a one year warranty from an outfit in Flordia. You folks think it's my screwup or the new flyback??? I don't claim to be an Einstein, but replacing it was pretty much a no brainer. Thanks.

"studebaker hawk" wrote in message
...

Well folks, I'm back.... I ordered a new flyback, got it yesterday,
installed it last night and no more snaps or flashes, in fact, I have
no picture or sound at all!!! If I turn the screen knob all the way up
I can get a horizontal line across the screen

You have no vertical drive. Something you did has resulted in that.

yea you lost your B+ to the vertical IC or the vertical IC is bad,. but you
should have sound.

im wondering if the secondaries of the FBT aint the same.



"studebaker hawk" wrote in message
...

David Naylor Wrote:
Homer J Simpson wrote:-
"David Naylor" wrote in message
. ..

-
sounds like the ever famous Sanyo flyback interal leak in the focus
block
section-


Is it the focus block or the flyback?


-
Yeh the focus block is part of the fly back part is about 14 dollars


Well folks, I'm back.... I ordered a new flyback, got it yesterday,
installed it last night and no more snaps or flashes, in fact, I have
no picture or sound at all!!! If I turn the screen knob all the way up
I can get a horizontal line across the screen and with the focus knob I
can make it fat and blurry or narrow and sharp for all the good that
does. I can hear the set click on when turned on, the filiments in the
neck of the tube will get orange although I don't believe at bright as
before, I can feel some static electricity on the outside of the tube,
but no illumination whatsoever and no sound at all through the audio
regardless of whether I have a signal or not.

After I got the old flyback removed, I cleaned the excess solder out of
the holes in the circuit board so I could place the new one, soldered
the connections on the back and replaced all the wires from where they
came from (I drew a diagram beforehand). Anyone have any ideas? My
solder joints all look good. I figured I'd better steer clear of the
Sanyo flybacks so to be on the safe side, I got an ACME brand with a
one year warranty from an outfit in Flordia. You folks think it's my
screwup or the new flyback??? I don't claim to be an Einstein, but
replacing it was pretty much a no brainer. Thanks.




--
studebaker hawk

Well I found out why I didn't have any sound or picture after I replaced the flyback, I had a bad connection on a wire. Stupid me! But anyway, I installed the new flyback and nothing has changed, same old flashing of picture accompanied with the static noise at the same time. So here's the scoop so far, the picture tube is ok (I removed the yoke and of course no picture but still have the noise) as is the flyback. Between flashes, actually I should say that I've probably incorrectly described what I call a flash, actually it appears there's a voltage drop whereupon the picture is lost, then regained. The picture and sound appears normal between the voltage drops. There's no visible arcing or signs of overheated components. The only component that gets hot is a 4,000 ohm resistor in the high voltage section, but it's a big one that's probably carrying quite a bit of juice. I cooled it down with freon (yep, still have some R12 auto freon left!) and nothing changed.

One fellow I talked to today mentioned something about a horizontal driver transformer. Does this make any sense to you folks? If so, I'd appreciate more details such as what does it look like, testing and so on. And and all suggestions or suspicions as to th epossible problem are greatly appreciated.

Thanks!

studebaker hawk wrote:

Well I found out why I didn't have any sound or picture after I replaced
the flyback, I had a bad connection on a wire. Stupid me! But anyway,
I installed the new flyback and nothing has changed, same old flashing
of picture accompanied with the static noise at the same time. So
here's the scoop so far, the picture tube is ok (I removed the yoke and
of course no picture but still have the noise) as is the flyback.
Between flashes, actually I should say that I've probably incorrectly
described what I call a flash, actually it appears there's a voltage
drop whereupon the picture is lost, then regained. The picture and
sound appears normal between the voltage drops. There's no visible
arcing or signs of overheated components. The only component that gets
hot is a 4,000 ohm resistor in the high voltage section, but it's a big
one that's probably carrying quite a bit of juice. I cooled it down
with freon (yep, still have some R12 auto freon left!) and nothing
changed.

One fellow I talked to today mentioned something about a horizontal
driver transformer. Does this make any sense to you folks? If so, I'd
appreciate more details such as what does it look like, testing and so
on. And and all suggestions or suspicions as to th epossible problem
are greatly appreciated.

Thanks!

I cant offer anything specific, but there arent too many places EHT
occurs in a tv, so it should not be too tricky to monitor them and
divide it down to find whats going on.

Removing the anode cap from the tube and replacing with a suitable load
would take the crt out of the equation, so youd know if that was the
problem or not.

Monitoring all crt electrodes will tell you which line the Vdrop is on,
thus eliminating several more bits. etc

Should at least narrow things down further.


NT

Well now here's something to chew on, it occured to me to try running the input (from a VCR) through the RCA jacks for video and audio. Using these jacks and with the TV set to video (only one video option), the sound is fine but the screen is totally blue. I know the VCR's fine because I hooked it up to another TV and both sound and picture came through fine. Don't know why I didn't think to try that before!!!!

So here's the deal, short and sweet. When I run the VCR output through the antenna connection, the picture flickers abruptly in and out accompanied by the sharp, snapping sound through the audio. Run the input through the video and audio jacks and the sound is fine but no picture whatsoever, just a blue screen. Does this bring up any ideas?

Thanks a lot!

studebaker hawk wrote:

Well now here's something to chew on, it occured to me to try running
the input (from a VCR) through the RCA jacks for video and audio.
Using these jacks and with the TV set to video (only one video option),
the sound is fine but the screen is totally blue. I know the VCR's fine
because I hooked it up to another TV and both sound and picture came
through fine. Don't know why I didn't think to try that before!!!!

So here's the deal, short and sweet. When I run the VCR output through
the antenna connection, the picture flickers abruptly in and out
accompanied by the sharp, snapping sound through the audio. Run the
input through the video and audio jacks and the sound is fine but no
picture whatsoever, just a blue screen. Does this bring up any ideas?


Thanks a lot!

its got nothing to do with it. sorry. If you dont want to do divide and
conquer on the relevant parts of the tv then I think youre out of luck.


NT