SOLVED! Wells-Garner D9200 "shake/jitter" issue

[Mrhide]

Splitting this from the "recent purchases thread"

ok : my D9200, 39 inches, after having recapped and all, still has "jitter" or "the shakes". it's actually displaying the same symptoms as this video from Mike: the curved borders + the shakes. the white (aka all colors) screen shakes the most, of course.

now that I see you mention the voltage regulator, and mike in the video fixes it as well with it, I'm hopeful that it might solve my issue? what do you think? these two are what I can see as "V REG":

Worth a shot?
thanks!

Always worth a shot! Jitter AKA “the shakes “ is usually a symptom of either failing caps on the power section of the chassis or a voltage regulator on the deflection circuit and/or caps. In Mike’s video it was due to a failing VR on the power section on the chassis. A common issue with that chassis(I have fixed one just like it. Thanks Mike!)
If those 2 IC are on the deflection part of the chassis, I would definitely give it a go. Just make sure you order the correct ones
Best of luck!
If those 2 IC are on the deflection part of the chassis, I would definitely give it a go. Just make sure you order the correct ones

So I changed them and at first I thought "well that did not help" and started to mess enough with the settings to finally remembered that when you work on chassis, being caps or other, it's a good idea to hit the "recall" button on the settings (and doublecheck the B+, which is 169.3 at R854. It calls for 170v so sounds close enough to me?!).

and... I think it's a lot better now! keep in mind it's a 39 inch! ( ok really a 36 viewable!)

I'm going to play with it again cause it's still a little too dark

it is still not perfect:
most of the time it's pretty good but depending on the colors displayed (the more white, the more issues) , it will still shake a bit and mess the pincushion briefly:

Suggestions and help welcome at this point (but I will continue to hit my head on it until it's perfect gosh darn it)

 

[BuddyC]

I would start checking components in the deflection area of the chassis. Diodes, resistors etc. Anything that looks suspicious.
I have read that the WG D9200 series was plagued by cheap caps and bad components, but since I don’t have first hand experience with this chassis, it’s just a educated guess.

 

[Mrhide]

I would start checking components in the deflection area of the chassis. Diodes, resistors etc. Anything that looks suspicious.
I have read that the WG D9200 series was plagued by cheap caps and bad components, but since I don’t have first hand experience with this chassis, it’s just a educated guess.

I have done the full 65$ nichicon cap kit. it helps but there's something else.
The story is that if it does FAIL it takes a bunch of stuff so I did it while it was still working!

it's an auto trisync monitor ! it's pretty cool when it works!

 

[BuddyC]

I have done the full 65$ nichicon cap kit. it helps but there's something else.
The story is that if it does FAIL it takes a bunch of stuff so I did it while it was still working!

it's an auto trisync monitor ! it's pretty cool when it works!

I would also check diodes and resistors. Especially resistors and diodes around the AC area. Did you change the filter cap?

 

[BuddyC]

Also found this:
https://www.wellsgardner.com/wp-content/uploads/2016/08/D9200_27_33_39_inch.pdf

 

[Mrhide]

I would also check diodes and resistors. Especially resistors and diodes around the AC area. Did you change the filter cap?

Ya on filter cap.

Ok will see if i can take a deeper look at diodes and resistors

Oh but important note:
The shake is *only* in 15hz! Nothing in 31hz! Even in the white and rgb screen of the test suite. That’s gotta mean something and that my research field is much smaller now right?!

 

[BuddyC]

If it’s only in 15khz, I would say that great news! As I said earlier, I have little to none first hand experience with this chassis, but I would check for bad soldering around pin cushion pot etc. Anything that has to do with 15khz needs an inspection.

 

[Arikado89]

Had same issue with my Super 29 candy cab. Replacing the filter cap fixed it for me.

 

[Mrhide]

there's also a loud BZZZ ONLY WHEN in 15hz! From mike's video, I was sure it was the flyback but when it turn it all the way off, it still makes the BZZZ.

I've poked around, with rubber gloves, and I believe the culprit is this guy, the 053X0664-001 D9200 Horizontal Drive Transformer:

My question is: can this "BZZZZZ" actually be what's making it shake? should I try replacing it?! ( you bet I will! )

 

[BuddyC]

A faulty horizontal drive transformer could definitely be the culprit! Go for it!

 

[Mrhide]

Done!

And here’s the uncensored version of the first try

 

[BuddyC]

Motherfu##er!
Can you test with another jammaboard?

 

[BuddyC]

I would post this on arcade otaku and hope that Grant will help.

 

[Mrhide]

hey at least the buzzing is gone right?! progress!

You can hear the before buzz here in this video I will probably post in other places.

 

[MickyMac]

Grant won't accept these for repair so he may not be able to help.

Mike has a few videos on them but not many.

I hope you find the solution.

P.S. a 39 inch CRT?!

 

[Mrhide]

P.S. a 39 inch CRT?!

Ya? I have 3 of them

 

[MickyMac]

Living the dream!

 

[Mrhide]

Can you test with another jammaboard?

I sure can.
It is weird : all boards are different.

This wonderboy is fine

Toki is also ok.
Konami appears good.

Neogeo is bad

The plot thickens. Time to sleep on it.

 

[Mrhide]

ok so this white shaking is called "Blooming" or "Breathing"

Blooming or breathing problems​

There are several symptoms that are basically similar:

• Blooming is defined as an expansion of the raster or horizontal sections of the raster with bright material. For example, switching between dark and light picture causes the size of the picture to expand by 10%. A slight change in size is unavoidable but if it is greater than 1 or 2 percent from a totally black image to a full white one, this is either an indication of a defective TV or one that is badly designed. The cause is poor low or high voltage regulation.
  Check the B+ to the horizontal deflection. This is usually well regulated. If it is varying in sympathy to the size changes, trace back to determine why the low voltage regulator is not doing its job. The reason for the size change is that the high voltage is dropping and reducing the stiffness of the electron beam.
  
  
• Expansion of the raster width in areas of bright imagery is an indication of short term regulation problems. The video drive may be interacting with the other power supplies. Check for ripple - this would be at the vertical scan rate - in the various regulated power supplies. The cause may be a dried up electrolytic capacitor - once you locate the offending voltage, test or substitute capacitors in that supply.

In both these cases, if this just started after some work was done to the TV,the brightness limiter and/or video drive may simply be set so high that the TV cannot supply enough current to the high voltage. If the brightness is acceptable with these turned down slightly and still have acceptable brightness, then there may be nothing wrong.

• Breathing is defined as a periodic change in the size of the raster which may be independent of what is displayed or its severity or frequency may be related to the brightness or darkness of the image. This is another type of regulation problem and may be caused by bad electrolytic capacitors or other components in the low voltage power supplies.
  If the TV uses a switch mode power supply or low voltage regulator separate from the horizontal deflection, first check its output(s) for a variation in voltage at the breathing rate. Test with a light bulb or resistor load to confirm that the problem is here and not the deflection or other subsystem of the TV.
  
  
• A condition with somewhat similar symptoms is bad focus - fuzzy picture - but only with bright (high beam current) scenes. This could be just a matter of adjusting the focus control but may also indicate sub-optimal filament voltage due to bad connections or components in the filament circuit, or a tired worn CRT. You won't get high beam current without some serious spot blooming (a fat beam because too much cathode area is used) and you will get cathode 'poisoning' after prolonged use.
  Visually inspect the neck of the CRT for the normal orange glow of the filaments and check for bad connections and bad parts

also

Breathing Compensation​

Breathing is a change in picture size caused by a variation of the EHT voltage due to varying beam current loading. The EHT has a typical output impedance of(approx.) 1 M Ohm. Average beam current varies between 0 and 2 mA, so the voltage drops by 2 kV (from 30 kV), or worse. At lower EHT, the electron beam is easier to deflect, so the picture size will increase.
Brighter picture -> higher beam current -> lower EHT -> larger picture.That's the law of physics.

The breathing can be compensated by decreasing the deflection current amplitude as a function of the beam current. A voltage called "EHT-info" is generated from the beam current as delivered by the line transformer. This is fed to the deflection circuit for feed-forward correction. For horizontal deflection this means feeding it to the East-West modulator.

And here's the catch for you Americans: many USA sets don't have an East-West modulator! Most picture tubes (for the USA) with 90 or 100 degrees deflection don't need (much) pin-cushion correction, so there is no fundamental need for the East-West modulator and so there is also no correction possibility for the anti-breathing. There are other options for corrections, like creating a deliberate higher output impedance for the V+ deflection supply etc., but these are passive measures which will lack accuracy.

Sets with 110 degrees deflection angle (common in Europe) will need active East-West correction and should also perform adequate anti-breathing. Although that is still difficult enough, I should know...

The LD/DVD "Video Essentials" contains test pictures to check your breathing performance. It advises you a simple counter- measure: reduce the beam current by lowering the contrast setting ! This will also improve the sharpness (less spot blooming) and increase the lifetime of the picture tube (less burn-in of the phosphors). But you need to darken the room because the picture will obviously be much darker.

...and that last part:
It advises you a simple counter- measure: reduce the beam current by lowering the contrast setting !


all these headaches for :

in retrospective:
take your time, check the basics!