What's new
What's new

Adjusting screen width - Mid 90s Okuma tube type monitor?

Wade C

Stainless
Joined
Jul 21, 2004
Location
Wiggins CO. USA
Trying to adjust the size of the display on the monitor on my 95 LNC-8.
I dug around in the back, and got vertical size and position found (little dials soldered on the board), also found the Horizontal Hold adjustment, and a brightness. But I tried every one I could see (6 in total) and only got reaction from the Vertical size, Vertical alignment, H-Hold, and the Sub-Brightness. The other two seemingly did nothing and I dont see any others in there that could be for Horzontal size/position.

Anyone able to verify that its just not possible? Or where I might look?

Not end of the world, just tweaks on my OCD a little not having the Fkey labels not line up with the keys below.

Oh, and any of you "older Okuma" guys ever have a lead on a floppy drive setup for the LNC8/OSP5020 - let me know. Ive been looking for a long time and came across one at an auction but things went to hell here and I didnt hear my alarm go off for the auction... so I missed it.


Thanks
Wade
 
Trying to adjust the size of the display on the monitor on my 95 LNC-8.
I dug around in the back, and got vertical size and position found (little dials soldered on the board), also found the Horizontal Hold adjustment, and a brightness. But I tried every one I could see (6 in total) and only got reaction from the Vertical size, Vertical alignment, H-Hold, and the Sub-Brightness. The other two seemingly did nothing and I dont see any others in there that could be for Horzontal size/position.

Anyone able to verify that its just not possible? Or where I might look?

Not end of the world, just tweaks on my OCD a little not having the Fkey labels not line up with the keys below.

Oh, and any of you "older Okuma" guys ever have a lead on a floppy drive setup for the LNC8/OSP5020 - let me know. Ive been looking for a long time and came across one at an auction but things went to hell here and I didnt hear my alarm go off for the auction... so I missed it.


Thanks
Wade

That's a nice lathe/ turning center, nice Japanese iron.

If you take and post a picture of the board (the little "Dials" potentiometers soldered onto the board ) + PCB it should be possible to figure out which is in effect the horizontal scaling amplifier for the 'Tube" / CRT. Horizontal sweep related circuitry / amplifier on relevant saw-tooth generator / control. The picture could be very reactive to small movements / adjustments on the sweep based circuitry. So Tweak with caution.


Not sure if there is an in-control adjustment for that maybe ? Not familiar with that control.


I'm guessing those are factory adjusted and locked out (for safety reasons/ mitigate confusion and time wasting ;-) ) as someone messing around with picture controls certainly could transpose the function keys and play havock / mayhem perhaps with an inexperienced operator ?
 
Im wondering if they dont make it adjustable... though for the reason you said they might lock it, is exactly why I want to adjust it. Right now, the F1 label is above the F2 key, and the F8 label is above the F7, and since most screens have a blank, it can be a bit deceiving. Obviously its not end of the world, but it just nags at me so I thought Id do some homework on it.

20190620_153714.jpg20190620_091954.jpg

The first pic is the back, you can see the 4 pots on the left, and two on the right. On the left, the blue one is vertical size, left of that is v-hold, right of the blue is H-hold, and behind the blue is v-lin which is alignment I found, as I adjusted the height and the alignment a bit while I was tinkering.
On the right side of the first pic, you can see the blue = brightness pot, and then the black knobbed one that did nothing that I could see when turned to min and max.

I didnt see it on the first two inspections (the flash washed it out) but after zooming in on the second picture, there is a label [WIDTH] that is left of the black knob, to the right of that small wire wrapped coil looking deal - right up against the plastic holder. But I dont see anything adjustable there at all, and its in line with that reddish brown looking thing (no clue what it is) and to the right of the wire wrapped coil thing (again no clue what that is).

So Im guessing that means their width is set by some sort of soldered in resistor and not something that can be adjusted... But Im hopeful that Im wrong and just not familiar with something Im seeing. Can try and get different or better pictures if there is something one needs to see from a different angle.

I love the machine... and have a second one Im working on getting going (time and money have hindered the progress).

Wade
 
I'll rummage around, got a couple of things to do etc. and also pretend to work (late), but I think you are very close to finding the adjustment, and I believe it can be adjusted. Just need to double check something.

Just remember these CRTs carry very high voltages that are lethal and also those capacitors still hold charge etc. even when powered down.

Back in the day (very old days) not unheard of that even very experienced people get killed by HT circuits/ charge on old TVs.
 
And thats exactly why I didnt get in there very far or very well. Last thing I wanted to do was find a charged cap and get bit. Heard many stories about that over the years... and Im a bit chicken naturally as it is - so that helps too. :P

Id love to change them out to LCD monitors but no point in spending that kind of money for something that doesnt need replaced... just to satisfy a bit of an OCD tick I have... :D

Thanks!
Wade
 
And thats exactly why I didnt get in there very far or very well. Last thing I wanted to do was find a charged cap and get bit. Heard many stories about that over the years... and Im a bit chicken naturally as it is - so that helps too. :P

Id love to change them out to LCD monitors but no point in spending that kind of money for something that doesnt need replaced... just to satisfy a bit of an OCD tick I have... :D

Thanks!
Wade

Haven't found time to rummage YET...

But there was this guy that lives in Switzerland (originally from Chicago and very well connected to the machine tool industry historically )that knows this stuff inside out like the back of his hand + all the variants of signal processing to a very deep level (real expert in that area); so knows very well old style CRTs and new LCD technology very well and how to upgrade and hack in a multitude of different ways. I think he got fed up with tangling with a certain three headed dingo*, cousin to Cerberus the three headed mythical dog that guards the Hellenic gates to hell. I think in the six eyes of said "Gate keeper" regarded him as too "Nerdy" (amongst other things) and flamed the hell out of him . Being proverbial shrimp on the 'Barbie" is not everybody's cup of tea.


There are other folks here that know these conversions well... But I recognize one of the key components on that board for what you might want to do (it's not SONY), just need to double check something, as I don't want to remotely and inadvertently trash you functioning display or get you 'Zapped".

It's not OCD as that kind of stuff can eventually drive you mad/ nuts Function keys not lining up with mis-scaled display etc.

Are you able to post a picture of the current misalignment / scaling error ? (front of the screen, there might be another work around for that .).

_____________________________________________________________________________________________________________


* Dingo - Wikipedia

* Cerberus - Wikipedia

* Dingus - Wikipedia
 
If (@WadeC) you can take a picture of the same circuit boards with the camera tilted 45 degrees downwards to show simultaneously the the top of the components as well as the 'Front face" on some of those components (as shown before in your previous shot). Then another shot, as a 3/4 view from left side pointing camera to center of board (horizontal plane level camera panned 45 degrees to right.).


Classic tech support stall tactic... No ~ just kidding; that would really help + front of screen mis alignment scaling etc.

I'm wondering with age whether there is a key component set of components that have drifted out of tolerance. Enamel insulation on various windings/ inductive components that start to get thinner and thinner just by heat / start to fail etc. [That's why mil spec electronics are so expensive as they have radically overrated components and have crazy long service lives, not so much with COTS.].

________________________________________________________________


OK I didn't see your second shot D'oh …

~ Reading about horizontal amplifier circuit design for CRTs, (actually going through a 100 page document just on the horizontal amplifier on the Tektronix oscilloscope as that is the closest match to a monochrome CRT that I have to hand.). Should be able to pin down exactly the horizontal amplifier + control circuits for that on your board.

Seems that there is partial safety shielding for the 10 to 20 KV circuitry on the Okuma display.
 
Im wondering if they dont make it adjustable... though for the reason you said they might lock it, is exactly why I want to adjust it. Right now, the F1 label is above the F2 key, and the F8 label is above the F7, and since most screens have a blank, it can be a bit deceiving. Obviously its not end of the world, but it just nags at me so I thought Id do some homework on it.

View attachment 259354View attachment 259355

The first pic is the back, you can see the 4 pots on the left, and two on the right. On the left, the blue one is vertical size, left of that is v-hold, right of the blue is H-hold, and behind the blue is v-lin which is alignment I found, as I adjusted the height and the alignment a bit while I was tinkering.
On the right side of the first pic, you can see the blue = brightness pot, and then the black knobbed one that did nothing that I could see when turned to min and max.

I didnt see it on the first two inspections (the flash washed it out) but after zooming in on the second picture, there is a label [WIDTH] that is left of the black knob, to the right of that small wire wrapped coil looking deal - right up against the plastic holder. But I dont see anything adjustable there at all, and its in line with that reddish brown looking thing (no clue what it is) and to the right of the wire wrapped coil thing (again no clue what that is).

So Im guessing that means their width is set by some sort of soldered in resistor and not something that can be adjusted... But Im hopeful that Im wrong and just not familiar with something Im seeing. Can try and get different or better pictures if there is something one needs to see from a different angle.

I love the machine... and have a second one Im working on getting going (time and money have hindered the progress).

Wade


OK,


So with a horizontal scan amplifier and the way the beam sweeps across the screen there a few "controls" that are engineered for to position the sweep / image correctly on the screen. These generally relate to the voltages on the left and right beam deflection plates on the cathode Ray Tube.

To over simplify, it's possible to scale the maximum and minimum voltage between these plates in various ways (or coils in the case of more TV like display/ monitor.). Basic crude scaling in width. Also it is possible to adjust the gain in amplification... Also possible to have an actual magnification circuit (more relevant to oscilloscopes),BUT you can have HORIZONTAL POSITIONING … Which keeps the image at the same scale but shifts the image to the left or right, this is a simple DC level horizontal deflection voltage (simple voltage shift on the left and right plates but the difference in potential remains the same between the plates. I.e. -250V on the left plate and + 250 V on the right plate , if you shift the voltage to -200 and +300 the potential difference is the same but the image shifts to the right (more or less with no significant magnification / scaling changes. So if it's 25 Volts /cm on screen deflection, then the image would (in this case) shift by 2 cms to the right. ). [These are example values not actual Okuma CRT values.].


The image is shifted to the right with your F1 / F2 mis-match (assuming correct scale) so that means that Black potentiometer on the right side could be broken , or a terminal is cracked … I.e. I'm thinking when it's zero / low resistance it shifts the image to the right, if it had useful resistance on half of its range it would center better. That shift could be accounted for by a voltage difference of just 24 volts (or of that order).

BUT if you say the F1 label is over the F2 key and the F8 label is above the F7 key then that means the image is not shifted but reduced in scale... Which may be set on the board with a non adjustable component... (hard to believe), or maybe you horizontal deflection coils are becoming weak/ weaker ? Back to horizontal magnification circuits. [Wondering if indeed Okuma doesn't have a provision for that unless there is some special feature on the control for that ? ]. Okuma probably didn't anticipate having their equipment be in service for so long ?




_______________________________________________________________________________


* To scale more linearly CRT's use a push pull voltage technique on the horizontal deflecting plates (or coils***, in the case of a more Tv like display). One is very negative (left side) and the right side is very positive. (the electron beam deflects in a more linear way by being pushed away from one plate and then being attracted by the other to create an accurate horizontal (linear/ more constant rate of travel across the screen horizontally.).


https://www.davmar.org/TE/TekConcepts/TekHorizAmpCircuits.pdf

^^^ Explanation in the techtronix horizontal amplifier description, the first ten pages explain how the saw tooth signal and horizontal sweep are created and how voltage shifting works to place and shift the sweep (scan/ signal / image) further left or further right. Various circuit diagrams are presented later that are more complicated (some parts of the circuitry can be ignored / "chopped out" in respect of a regular monochromatic display ), but most of basic stages and circuitry and the way they are controlled are pretty much the same (electronically) in principal.

*** Regular TV's differ from oscilloscopes from their raster scans as those tubes are much more wide angle and rely on magnetic deflection coils much more but the circuitry for horizontal amplifiers and image position principals are pretty much the same.


>>> Will edit look at again some time tomorrow (time willing).
 
No direct experience with okuma, but;

Horizontal width on old industrial mono crts is usually factory set. Shift probably indicates dead or dying electrolytic caps.

However, if you don't want to mess around with a recap and just want to extend the life short term, the horizontal width is probably set by that adjustable inductor next to the flyback transformer. Be careful if you try to turn it. The ferrite cores are fragile.

Alternatively a brute-force replacement of all the electrolytic caps you can find on the board is a fairly simple and cheap job if you are ok with a soldering iron.

Note the probably's; This has been my experience with other industrial crts, no absolute guarantee that yours is like this.
 
No direct experience with okuma, but;

Horizontal width on old industrial mono crts is usually factory set. Shift probably indicates dead or dying electrolytic caps.

However, if you don't want to mess around with a recap and just want to extend the life short term, the horizontal width is probably set by that adjustable inductor next to the flyback transformer. Be careful if you try to turn it. The ferrite cores are fragile.

Alternatively a brute-force replacement of all the electrolytic caps you can find on the board is a fairly simple and cheap job if you are ok with a soldering iron.

Note the probably's; This has been my experience with other industrial crts, no absolute guarantee that yours is like this.


I was wondering whether in general the scaling of the image i.e. getting smaller over time (especially width symetrically) was from the power supply slowly dying over time… general voltage drop. So as you say replacing all those electrolytic caps.


I was leery of getting OP to adjust that "Adjustable inductor" just in case it does something else and is very factory set, and YES exactly as you say if it has a ferrite core it can be very fragile. I was hoping to get a shot from OP that shows the face of the core on that inductor. I was wondering if it had like a factory adjusted "setting" that then gets red marked and physically glued in to that position.


@WadeC Gregor is pointing to the thing with the copper windings sitting next to the big reddish brown thing (component) you alluded to earlier.

Can you get a picture of that face on ? / close up. You can shoot through a magnifying glass if you have to ?

Some of the circuit diagrams I looked at (depending on vintage) had straight up potentiometers for horizontal adjustments, but only really really old ones did I see linked inductors for these kinds of adjustments. DC circuitry versus inductive and phasing electronics like for synching/ phase shifting … So the look of that variable inductor kinda scared me as it looked like something that you could adjust and never be able to turn back without breaking it or just messing up some knarly ac phase related electronics lol. [It looks quite big so wondering if that adjustable inductor is more power / grid voltage related... That might scale up the image, step up the voltage by 5% . ]. Also concerned if there is indeed a slow death voltage drop (over many years), generally if the voltages are scaled up to compensate does that accelerate the failure and fritzing out of other components, like you (@gregor) are saying replacing all the electrolytic capacitors etc.

Dumb question is there an Okuma maintenance manual for this... Maybe later I'll endeavor to dig up some more relevant circuit diagrams etc.


@WadeC can you take a more general shot of the back of the tube showing the coils on the tube itself, just trying to get a handle on their size and mangnitude as that inductor that Gregor is pointing to may indeed be the ticket.
 
Thanks for the input guys.

Attached two pics of screens - First Pic - one with two columns is the machine that original pictures were from. I fired up the other (same model/year but a bit older in serial numbers) and attached view of that ones screen as well. They both could use a little widening, but the first one is obviously worse.


20190621_084545.jpg20190621_083236.jpg

They both have had the veritical size and location adjusted a hair, but werent too bad at all.
Here is a pic of the inside of the other, look identical other than the red marking on top of the caps, and a little difference on the inside of that wire wrapped deal next to the [width] marking (Im guessing this is the "inductor next to the flyback transformer" that gregormarwick is talking about? I am very illiterate when it comes to a lot of board level components) - That difference is on the first machine, it looks like a rod of graphite in the inside of the clear plastic center tube - on the second machine, it has a blue little plastic piece that has a hex socket in it.

I wish I knew more/understood more about this kind of stuff. Its always fascinated me but has also always alluded my grasp. Guessing just never found an explanation that my mind could grasp.

Here are similar pics as the first machine, but of the older/second machine. I tried all the knobs/pots on the second machine, just as I did on the first... and all the same results. Black knob did nothing I could see at all. And I did find that before, I thought the V hold didnt do anything, but apparently I hadnt turned it all the way each way - both machines it does in fact lose its vertical hold going to extremes on it. So the 4 on the left all seem to do what the labels suggest.
20190621_084851.jpg20190621_084925.jpg

I did look at the 3 legs of the black knobbed pot, and they dont look cracked nor loose at the board on both machines, and neither one on either machine does anything.


gregormarwick
Im not great with a soldering iron, but getting better. But if I went with cap replacements, Id probably check with a local tv place and see what they would charge to do it. But if I end up figuring out what would need to be done to retro a LCD in there and got the parts - once I had the back up/replacement on hand, if I hadnt dont it yet, I might try it for learning/practice. :D Though I would also want a little pointer as to what are the high voltage points so I knew where to look out and avoid :O

Thanks again!
Wade
 
Thanks for the input guys.

Attached two pics of screens - First Pic - one with two columns is the machine that original pictures were from. I fired up the other (same model/year but a bit older in serial numbers) and attached view of that ones screen as well. They both could use a little widening, but the first one is obviously worse.


View attachment 259376View attachment 259375

They both have had the veritical size and location adjusted a hair, but werent too bad at all.
Here is a pic of the inside of the other, look identical other than the red marking on top of the caps, and a little difference on the inside of that wire wrapped deal next to the [width] marking (Im guessing this is the "inductor next to the flyback transformer" that gregormarwick is talking about? I am very illiterate when it comes to a lot of board level components) - That difference is on the first machine, it looks like a rod of graphite in the inside of the clear plastic center tube - on the second machine, it has a blue little plastic piece that has a hex socket in it.

I wish I knew more/understood more about this kind of stuff. Its always fascinated me but has also always alluded my grasp. Guessing just never found an explanation that my mind could grasp.

Here are similar pics as the first machine, but of the older/second machine. I tried all the knobs/pots on the second machine, just as I did on the first... and all the same results. Black knob did nothing I could see at all. And I did find that before, I thought the V hold didnt do anything, but apparently I hadnt turned it all the way each way - both machines it does in fact lose its vertical hold going to extremes on it. So the 4 on the left all seem to do what the labels suggest.
View attachment 259378View attachment 259379

I did look at the 3 legs of the black knobbed pot, and they dont look cracked nor loose at the board on both machines, and neither one on either machine does anything.


gregormarwick
Im not great with a soldering iron, but getting better. But if I went with cap replacements, Id probably check with a local tv place and see what they would charge to do it. But if I end up figuring out what would need to be done to retro a LCD in there and got the parts - once I had the back up/replacement on hand, if I hadnt dont it yet, I might try it for learning/practice. :D Though I would also want a little pointer as to what are the high voltage points so I knew where to look out and avoid :O

Thanks again!
Wade


I think Gregor may be right about the variable inductor as the "WIDTH" setter as factory set. As it says in friendly letters on the board / PCB.


The graphite "Thing" is a ferrite magnetic core. They are very fragile.

On the second machine the adjustable inductor HAS a hex bolt, possibly by shifting the inductive core you can change the horizontal scaling voltage.

However
That photo of the front screen showing barrel distortion and a smaller image is very tell tale. Glad you posted that, and I can also see that you have changed the aspect ratio of the image significantly (vertically to compensate) lol … I'll dig some stuff up later on today.


Also those types of potentiometers (like the black knob) do fail (electronics from the 80's I remember like my volume control on my ghetto-blaster, and other ), sometimes you have to press down on the dial (supported) for it to make contact, they can lift and loose contact. But usually from use rather than just sitting there. Having a "Knob" that literally does nothing is interesting... If it did do anything and worked I would bet on horizontal positioning but that does not seem to be your problem, rather than more general slow death shrinking image barrel distortion on screen.

___________________________________________________________________________________________________


Honestly if it were me in the interim I'd probably get a strip of laminated card board and put diagonal lines joining the borders of the function keys with the corresponding borders of the barrel distorted and partially shrunk displayed function tabs. ;-) Another OCD yet half asred hack … (to help reduce general irritation ) lol
 
Couple more pics (I hope I captured what you were wanting to see ) take from the original machine I was talking about (newer of the two - and for above picture reference - the first post of pictures where the caps do NOT have red on the top of them)

20190621_092216.jpg20190621_092233.jpg

You can see the lack of the hex socket in this one (as compared to the one in the pic from the older machine with the blue plastic in the end). I didnt go poking in there, could be a blob of glue or something covering the hex socket?

Thanks again for the time and input. I appreciate it. Especially since this is more of an pet peeve than a "I cant run and need to" situation.
Wade
 
But if I end up figuring out what would need to be done to retro a LCD in there and got the parts - once I had the back up/replacement on hand, if I hadnt dont it yet, I might try it for learning/practice. :D Though I would also want a little pointer as to what are the high voltage points so I knew where to look out and avoid :O

Thanks again!
Wade

About 3 months ago I had a customer that had a bad CRT on a Hardinge lathe. It was a Fanuc but he bought the LCD retrofit on ebay for $350 as opposed to $1900 for a Fanuc refurbished unit. He said it arrived the next morning and was plug and play so it took no time at all to install. This customer isn't very technically inclined so it must have been pretty straight forward. Unfortunately the Okuma LCD is about $500 more than the Fanuc and the seller states 60 minutes to install as opposed to 10 minutes for the Fanuc.

Attaching the link below. Daryl

Okuma 5020 LCD Retrofit
 
Thanks Daryl, Yeah I saw that before I ever even posted up here... thinking if I could do a LCD for a few hundred bucks, I wouldnt lose any sleep, save a few pennies, and just replace them. But yeah... not so lucky.

Im guessing there is some sort of converter necessary, OR, they are just following the Okuma pricing scheme, which despite being great machines... parts costs are sometimes a little silly.

Wade
 
OR, they are just following the Okuma pricing scheme, which despite being great machines... parts costs are sometimes a little silly.Wade

Ain't that the truth! Got a quote for an aluminum 6 groove 6" diameter spindle motor pulley for a customer once, $4k. They chose to install the used one. :)
 
I think I've got it / narrowed it down to one component now.

Will write it up / diagrams etc.

______________________________________________________________


I think the key point that is emerging with these vintages of machines that the replacement parts are expensive or no longer stocked so having to hunt down and isolate that one $5 component that can be easily replaced, and potentially save hundreds if not thousands of dollars is certainly worth while.

Both on the Fanuc and Okuma and other fronts.

For some of this casual reverse engineering of outdated proprietary information by collectively "Muddling through" may be required to build up a bit of a knowledge base on these vintages of machines 'cuz the IRON is really good !

_____________________________________________________________

The guys / sources of information on fixing these kinds of monitors and CRTs are (in a lot of instances) 'Peeps" who build and rebuild and restore 'Vintage" and retro arcade games , like the stand up kiosks in arcades... [My local laundromat still had Mis-Pacmac and Galaxian ;-) ].
 
Ok from what I've been reading / digging around,

That set of components associated with horizontal adjustments ALSO control the amount of barrel distortion vs pincushion effect on screen. [barrel distortion, the straight sides of the displayable rectangle are bowed outwards by various degrees and "Pin cushion" is bowed inwards... The careful balance between the two is straight rectangular sides.].

In this photo you took …


okuma monitor 9.jpg

You can see a specific arrangement of components that has an inductor / mini transformer (the coily coppery winding thing), a largish capacitor, (the browny red thing you were referring to earlier), a specific combination of diodes and resistors further back in the frame.


That set of components corresponds to this...


Monitor arcade wg_k4600-hmm1 (1).jpg
...

Monitor arcade wg_k4600-hmm1 cropped  (1).jpg

^^^ Is possible to click on this image and blow up.

better grab 1 .jpg

^^^ Capacitor labelled in this diagram as C613 next to the 220/25v designation next to the inductor/ transformer. (notice the horizontal "Size" coil in the top right of the diagram immediately above (as well)).

^^^ This is from a K4600 monitor , not a bad analog of the Okuma monitor, but not the same / identical of course.

In the top central portion of the diagram you can see some of the labelled components that tend to fail for barrel distortion and control of the horizontal coils of the CRT.

Usually it seems that that capacitor as labelled is the one that fails... (I believe that corresponds to the big red-brown looking component). Not sure exactly what the 80619 512T is doing ? [Will take a closer look at that.].


It's usually stated that the pin cushion / barrel distortion control is controlled by that capacitor through a resistor or variable resistor... But if that capacitor is not doing it's job then when you adjust that resister nothing will happen … (Maybe what you are seeing here with the black knob not really doing anything and the barrel distortion / pin cushion control is fritzed out to maximum barrel distortion and minimum default sweep width. ).

On the circuit diagram right of the arrows is an inductive transformer for the horizontal coils, looks like a right hand curly spiral with verticall dotted lines adjoining a left hand curly spiral … (these are symbolic of primary and secondary windings.).


___________________________________________________________________________________________



So a bit like what gregorW was saying that inductor / mini transformer is adjusted in the factory , probably by moving the core in and out a bit and then glueing it in one position, that would set the basic width of the horizontal sweep on screen, but I would not attempt to adjust it as it does not look that 'Adjustable". Some do some arn't hard to tell unless you are able to get up close to inspect.


_______________________________________________________


@WadeC it could be all that needs to be replaced is that one brown capacitor... So you could take that to an old school TV repair man or "Peeps" that do retro arcades to fix that / replace that capacitor.

It also maybe that those RED markered electrolytic capacitors on the board have already been replaced and maybe someone tried to fix the monitor by replacing those capacitors and just colored then to mark out which ones he or she already replaced and then maybe gave up.

_____


____________________________________________________________________


@WadeC can you see any numbers marked on the brown capacitor or the PCB (Printed Circuit Board) ? Does it say something like 0.025 ? or 25 µF or something like that ? + voltage rating ?
 

Attachments

  • close up .jpg
    close up .jpg
    15.9 KB · Views: 49
Ill see if I can find any other numbers on the brown round guy...

Keep in mind, the caps with red are from the other machine that has less issue on horizontal size. Just mentioning. None of the caps on the first machine (and one needing adjustment worse) are red on top.

I wont lie, I have a hard time making heads or tails of some of the schematics, but Im working on digesting it. :D

Thanks again for taking the time! Im not sure Ill ever be able to understand it all, but Ill certainly try! This kind of stuff fascinates and baffles me at the same time. :P

Will report back about any labeling on the brown cap
 








 
Back
Top