Sharp Image SI-134 / KTM-F 33 Vertical Collapse++

I'm also always going to be annoyed at unabashed shill behavior. So, dude's starting a step behind.
Agreed.

I've started making premade lists on Digikey that anyone can use to make a capkit order. Anyone can add them to their cart, and they have the positions listed on them for each kit.

I'm doing this out of spite, to save money, and because it's more efficient.

When you order them on digikey they come individually bagged with the proper position. Usually by the next morning (At least to me in Calgary Alberta), with free shipping if you order enough at one time.

…I don't know, maybe stop injecting ads into other peoples threads that know your well known business exists…? Just a thought…

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(Oh, that assembly price is in Canadian, so that would be about $14 usd at the time of writing.)

When I get more time I'm gonna make a thread with as many Digikey lists as I can. I think maybe some kind of easy to understand tutorial video on how to find your own parts and make your own kits might be in order as well. Maybe I'll start posting the video link in his threads?
 
I posted a while ago about this chassis, have done some troubleshooting, replaced some parts, but still no joy.

Repair log thus far:
Following the schematic, in order from the point that sync enters -
R524 1 ohm in circuit (10k ohm out of circuit which is what it's listed as, seems ok. No idea what it should read, as I don't have a working chassis to compare)
IC501 no shorts, all pins have continuity to the next pad they lead to
C523 This one stumps me. I have a BSIDE ESR02 ESR meter I use to test caps. This cap comes up as two diodes with a reading of "uF=2.37v 2.09v." Ordered replacement to see what happens
C524 Same thing, except the reading is "uF=3.55v 4.48v." No idea what is going on here. Ordered replacement


Outside of that section I found some other components not reading correctly and replaced them:
R903 reading 1k ohm in and out of circuit, should be 15. Replaced
Filter cap read low, replaced
C205 read low, replaced
IC201 It was recommended this be replaced in a troubleshooting guide I found about this model. This was replaced by someone before me, and they lifted SO MANY PADS. I replaced the IC with a new one and was able to get continuity to each pin. Pin 11 seems to lead nowhere, though, so can't test that one.

So, while waiting on shipping to replace the two other two caps (C523, C524), I put the chassis back in to see if any of my fixes made a difference. Well, it did, sort of. I still have vertical collapse, but it's slightly higher and now there is a faint but noticeably new high pitched squeal. The squeal changes pitch when the screen pot is adjusted on the flyback, and is present when the pot is turned all the way down.

So... given all that: what's next? I'm at the limit of my knowledge and abilities for now. Hope this makes sense to someone else.

I've glanced through this, and have seen the thread go in a couple different directions. What EXACTLY is the monitor doing or not doing right now? And can you post a picture of the screen? I think it's in partial collapse, but I may be wrong.

By the way, these chassis are on my list of counterfeit parts that I don't really like repairing (voltage regulator is difficult to get and/or expensive). However it sounds like that is not your problem. Let us know.
 
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Agreed.

I've started making premade lists on Digikey that anyone can use to make a capkit order. Anyone can add them to their cart, and they have the positions listed on them for each kit.

I'm doing this out of spite, to save money, and because it's more efficient.

When you order them on digikey they come individually bagged with the proper position. Usually by the next morning (At least to me in Calgary Alberta), with free shipping if you order enough at one time.

…I don't know, maybe stop injecting ads into other peoples threads that know your well known business exists…? Just a thought…

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(Oh, that assembly price is in Canadian, so that would be about $14 usd at the time of writing.)

When I get more time I'm gonna make a thread with as many Digikey lists as I can. I think maybe some kind of easy to understand tutorial video on how to find your own parts and make your own kits might be in order as well. Maybe I'll start posting the video link in his threads?
yeah i think you should make all the kit lists so i don't have to as i have over 1000 kits (but remember if you aren't going to do them all your wasting everyones time) but in about 6 months your lists will have out of stock, obsolete, or discontinued caps in them so make sure to keep supporting people by continuing to update them so they don't get out of date. you @ChanceKJ are the exact reason so many vendors quit making their cool parts and you never seen them again as you DON'T SUPPORT THEM you would rather support Digikey which there are hundreds of thread with people complaining something isn't available anymore. i have supported a ton of different vendors on here and bought things i didn't even need just so a new product would be introduced and available, i have also offered to fund them or buy them and put them on our site to help, i support this site every year, i have supported a ton of threads for people needing help which i even contributed to bob roberts bike years ago and i continue to help people everyday with questions as i field 50-100 emails daily, post on different forum around the world and YES even post links to parts we sell that they can buy or buy it somewhere else but at least they know its available. so i contribute many thousands of dollars each year, thousands of hours of my time each year for this hobby so what have you done and whatever it is will it last for more then a short time?? i would be further ahead to just shut this down as it usually looses money and that is after my other company pays for all the payroll of four family members and many other costs so no i have never received a dime for all that i do, so instead of always criticizing why don't you actually do something new to help out instead of copying what is already out there. this goes for @Esom also.

BTW: i will bet you digikey doesn't have in stock close to 75% of what we sell so find another source for that too while your at it.
 
Alright, since no one has further thoughts on the actual thread anymore, let's discuss the new topic.

You know that old trope about "Good / Fast / Cheap -- Pick Two?" In this case, both options (Digikey and APR) are like a "Pick One...and a bit."

APR has pre-made kits, that's easy. The cost is higher and the shipping is slower. But you also have the problem of getting caps that may not be populated on your particular PCB, or whatever. It's out of your hands. Not a big deal, but that's not the crux.

Digikey has a fantastic search and filter feature, but you do have to have made a list. That's hard. But the shipping (in the US anyway) is pretty much always $7 and two days. Versus, also not a big deal, ~$12 per round of purchases, no choice in selection, eh... but the waiting, that's my deal breaker.

I'm always going to go with which ever presents it self as the most convenient. I don't mind scanning my parts and making lists. That's pretty fun, to me. Digikey doesn't stock old AMP El connectors and vertical ICs, so sometimes APR wins on a technicality.

I'm also always going to be annoyed at unabashed shill behavior. So, dude's starting a step behind.
you don't need to compare just buy from digikey if you prefer to support them instead of people in our hobby community plus apples to apples our caps are very close or cheaper in 100packs and even 10packs on our site. we ship the same day M-F so we can't help usps sucks and that is why later this year i will be moving to UPS.
 
What EXACTLY is the monitor doing or not doing right now? And can you post a picture of the screen? I think it's in partial collapse, but I may be wrong.

By the way, these chassis are on my list of counterfeit parts that I don't really like repairing (voltage regulator is difficult to get and/or expensive). However it sounds like that is not your problem. Let us know.

Oh snaps, back on topic, awesome! Right now, it's doing nothing because I don't have the correct resistor for R901. Just before that, a single, very bright horizontal line on the tube. Might be 1 or 2 pixels tall, not sure because it was immediately followed up with a burning, smoking hot resistor at R901. I really don't know if that is a new symptom or a result of an improper resistor at R901 (Aside: It was a 15ohm to begin with, toubleshooting guide says 15ohm. But schematic says 1.5ohm so I figured, why not. Insert 1.5ohm, burn out R903. So I'm going back to 15 at R901 and a new 3.5k or whatever it was at R903). Just before THAT there was also a high pitched squeal, but that seems to have gone away after recapping.

Total repair list so far:
All e-caps replaced, including filters. C108 and C109 were bipolar, replaced with polar according to schematic and silkscreen.
IC201 replaced (purchased from GrumpyPuss above)
C521, C523, C524 c-caps on hand, not replaced yet
Reflowed just about everything, except the two vertical breakout PCBs
 
Update: R901 replaced, instant over heating and smoke. So it's not R903 setting it off.

Looking at the schematic, R901 is the first component coming off pin 7 of the flyback. So is the Flyback sending too much voltage? How do I test that? Should I temporarily install a beefier cement resistor and see what happens?

The next components after R901 are D901 and C901 in parallel. C901 is testing properly. D901 gives a .49V drop in one direction, and nothing in the other. Not sure how it's supposed to read. Issue here?
 
@security0001 , I appreciate what you do for me and the community, even though you inexplicably ruffle some feathers with a post or two of self-promotion. God forbid anyone does the same around here.

Please understand these yahoos are in the minority. Most of us know your worth. Please KEEP ON KEEPING ON.
 
yeah i think you should… TL/DR

Dude its not a fucking personal attack.

I've spent over half my life consulting for business exactly like yours for both their online and brick and mortar Marketing/eCommerce/logistics. What you're doing is tacky, annoying, and in poor taste.

Just stop being such a shill in everyones fucking threads and go back to being cool.
 
Dude its not a fucking personal attack.

I've spent over half my life consulting for business exactly like yours for both their online and brick and mortar Marketing/eCommerce/logistics. What you're doing is tacky, annoying, and in poor taste.

Just stop being such a shill in everyones fucking threads and go back to being cool.

Wait.. are you THE CHANCE... the one that's in the movie industry??!
 
Oh snaps, back on topic, awesome! Right now, it's doing nothing because I don't have the correct resistor for R901. Just before that, a single, very bright horizontal line on the tube. Might be 1 or 2 pixels tall, not sure because it was immediately followed up with a burning, smoking hot resistor at R901. I really don't know if that is a new symptom or a result of an improper resistor at R901 (Aside: It was a 15ohm to begin with, toubleshooting guide says 15ohm. But schematic says 1.5ohm so I figured, why not. Insert 1.5ohm, burn out R903. So I'm going back to 15 at R901 and a new 3.5k or whatever it was at R903). Just before THAT there was also a high pitched squeal, but that seems to have gone away after recapping.

Total repair list so far:
All e-caps replaced, including filters. C108 and C109 were bipolar, replaced with polar according to schematic and silkscreen.
IC201 replaced (purchased from GrumpyPuss above)
C521, C523, C524 c-caps on hand, not replaced yet
Reflowed just about everything, except the two vertical breakout PCBs

Okay, in the manual I have, they changed parts on the 29in and 33in monitors, from the 14in. One of those changed parts is R903 2watt 15ohm.
R901 is not changed on the 33in, and should be 3.9ohm at 1watt. This is a high failure part, so if it's original that could be a problem.
You're saying right now it's doing nothing. Does that mean, no neck glow, no high voltage and no B+ voltage?
If you want to check your voltage off of the flyback pin 7, check it at the cathode of D901 (the side with the stripe), Maybe 12volts? The schematic isn't written well and I'm just guessing.

#1: Make sure R903 is a 2watt 15ohm, you're saying it's 3.5k at R903 that may be causing the collapse.

#2: R901 is not changed on the 33in, and should be 3.9ohm at 1watt. This is a high failure part, so if it's original that could be a problem. Make sure R901 is 1watt 3.9ohm.

#3: C521, C523, and C524, just check those to ensure they are not shorted and you should be ok.

#4: What is going on with C909, is it installed? (220uf @ 50v) It looks like it was not installed from the factory. It says in the manual that you are to REMOVE C909 on the 14in and there is no change to that on the 33in. So it should not be installed.

#5: R903 is directly on the vertical circuit. Caps connected to it are C614, C615 and check L603 also (should read very close to short). Make sure the caps are soldered in correctly (polarity and connection to next pad)

#6: You have 2 caps tied to the V.D.Y. that are 1000uf. C202 is the closer one which I believe is your boost cap. However C906 is a little further away. Check both of those (polarity and connection to next pad). Let us know what you find (I have a feeling it's the R901 and R903 situation.)

P.S. C500 is right above IC501 on the top lefthand cornerish of the board. Above IC501 is a poly cap, 2 resistors, a poly cap, a resistor, and then C500 is hiding there (this is once again the picture of the 14in version but should be the same)
 

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Sorry, typo on the 3.5k, meant3.5ohm, tho I see it's actually 3.9ohm, which is what I have installed. It was doing nothing because I couldn't turn it on until some parts came. They've arrived, been installed, and R901 is still burning out immediately on power on. Neck glows, static builds from tube powering up, but R901 going poof so fast I don't even know if I still have vertical collapse because I have to turn it off so fast.

To your points:
#1: On my schematic, R903 should be 1.5ohm 2W. It was 15ohm, and I changed it to 1.5. The burnout on R901 happened, so I changed R903 back to 15ohm, which it is now. Currently: R903 Is 15ohm 2W.
#2: R901 is 3.9ohm 1W. It's the one that keeps burning.
#3: C521/523/524 are not shorted. Just giving odd readings on my ESR meter.
#4 Yeah, I believe C909 is not installed. I purchased the cap when recapping the whole thing, only to find it was not populated, so I left it out.
#5 C614/615 replaced in total recapping. L603 I don't have any notes on, so I guess I missed that. Will check first thing tomorrow! (It's in my shop, not my home, unfortunately)
#6 C202/906 were both replaced. I feel like I was pretty meticulous with following the silkscreen, but I'll check them too.
#P.S. Ah ha! Thank'y

Thanks, nice to have guidance again.
 
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Yeah, couldn't hurt to measure the voltage at the cathode of D901.

And C500 is an electrolytic.

There is way too much current going to R901. Check pin 7 of the flyback, but maybe also check D901, C901 (is it shorted?) and maybe C902 (is it shorted or a solder blob to ground on the positive end?) C903 is also on the same circuit with the negative tied directly to ground, I guess you can check that one also to see if it's shorted or a solder blob.

You have something shorted somewhere. Which could be a backwards cap, or a solder blob also.

And yes don't leave the monitor on and watch R901 catch fire, that's dangerous. :)

I guess with changing those resistors around, you could have damaged that winding of the flyback, also.

This is definitely a head scratcher.

Edit: I think you're in HV shutdown, but we really need to figure out why R901 is smoking. We fix that, and I think we can move further to see if you need a flyback. But just to verify, before you did your work on it, you were in vertical collapse, is that correct? Not after?
 

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Edit: I think you're in HV shutdown, but we really need to figure out why R901 is smoking. We fix that, and I think we can move further to see if you need a flyback. But just to verify, before you did your work on it, you were in vertical collapse, is that correct? Not after?

Correct, this all started with vertical collapse. The first thing I did was change the caps related to the vertical section and IC201. That didn't change anything. Next I noticed the resistors didn't match the schematic. The burning resistor only began after changing the R903's 15 ohm resistor to 1.5 ohm. Changing it back to 15 ohm didn't save R901. Complete recap also didn't save R901.

Edit: New thought, is the voltage rating of the resistor important in this position? I have no idea how much voltage is coming off pin 7, but would it be higher than 300V? Because that's the rated working voltage of the resistors I'm using.
 
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C500 located and replaced. It has no markings on the solder side! That's annoying.

L603 reads 0.6ohm. Contact to all adjacent pads is good.

All caps checked for polarity, found to be correct.

How would I go about checking pin 7 on the flyback?

Edit: another thought. I have been powering on the monitor with the screen pot turned all the way down to prevent burning in the horizontal line. Is that possibly forcing too much voltage through?
 
Yeah, couldn't hurt to measure the voltage at the cathode of D901.
Well, I haven't tried this yet. How do I attempt this safely?

One lead on the cathode to the multimeter, one lead to... frame?

Not sure of the expected values, but getting 47ohm one way, OL the other, out.of circuit.

Edit: also found that IC601, pins 5 and 7 are close to shorted? .5 to .7 ohm. Normal?
 
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Black meter lead on the metal casing around the flyback as that is chassis ground. Red lead on cathode (white striple) of D901 (DC Volts).

What is the part # on your IC601, I bought some but not sure if they are counterfeit or not. If it's the same part # I have, I'll check one of mine. (I think it's supposed to be an STR-S5741).

@security0001 I don't see the STR-S5741 on your site, do you have a cross reference for it?
 
Okie dokie, gonna try that.

Yes, mine is a STR-S5741. No manufacturer's name is printed on it.
 
Black meter lead on the metal casing around the flyback as that is chassis ground. Red lead on cathode (white striple) of D901 (DC Volts).
3.69v at the cathode of D901. R901 burns up in about 10 sec.
 
3.69v at the cathode of D901.
Yeah that's a problem at this point I would say it's probably a fly back that's the issue that secondary voltage there is it should be 12 I think
 
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