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Author Topic: Vector-gasm... Cosmic Chasm!  (Read 4523 times)

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PL1

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Re: Vector-gasm... Cosmic Chasm!
« Reply #40 on: March 15, 2023, 10:44:55 am »
No matter what I may hear from anyone about component heat tolerance I will be putting a fan on this heat sink also.
Only question is should it be mounted directly to it or not and should it be pushing or pulling in relation to air movement across the heatsink.
For an open layout like your setup, I'd go with push for better directionality.
- Pull will draw air from the path of least resistance.  The far side of the heat sink will not get as much air flow.

I'd probably put the fan(s) to the left of the heat sink and slightly above it, blowing parallel with the cooling fins and slightly downward so the air blows through the entire length of the fins.


Scott

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Re: Vector-gasm... Cosmic Chasm!
« Reply #41 on: March 15, 2023, 02:58:46 pm »
I was thinking along the same lines but wasn't sure if my thinking was correct.
Only other possibility was is it even better to put the fan in the side of the cabinet and have it draw air from outside to blow across the heatsink.
Thanks as always for your thoughts Scott!

No matter what I may hear from anyone about component heat tolerance I will be putting a fan on this heat sink also.
Only question is should it be mounted directly to it or not and should it be pushing or pulling in relation to air movement across the heatsink.
For an open layout like your setup, I'd go with push for better directionality.
- Pull will draw air from the path of least resistance.  The far side of the heat sink will not get as much air flow.

I'd probably put the fan(s) to the left of the heat sink and slightly above it, blowing parallel with the cooling fins and slightly downward so the air blows through the entire length of the fins.


Scott
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

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Re: Vector-gasm... Cosmic Chasm!
« Reply #42 on: March 17, 2023, 08:49:30 am »
Tomorrow hopefully I can go buy a stack of refrigerator magnets (the thin flexy kind of bits you can cut into strips- it is what I have seen on tubes anyway) and begin experimenting.

From what I've heard, fridge magnets are not great for convergence strips.

Some seem to have better luck with craft knife blades, which can be snapped to appropriate size, and magnetising them by running a permanent magnet along them a few (?) times. Then you wrap them in tape and position accordingly.

If you are ever trashing an old CRT, is a good idea to grab any useful bits like convergence strips, rubber yoke feet, degaussing coils, maybe even the yoke itself.

Quote
No matter what I may hear from anyone about component heat tolerance I will be putting a fan on this heat sink also.
Only question is should it be mounted directly to it or not and should it be pushing or pulling in relation to air movement across the heatsink.

Also looks like I will be putting some good size vent holes in this cabinet.

Scott's right, have the fans blow over the heat sinks. I'm thinking you could use multiple fans, maybe two 4" fans? I'd also suggest a large fan (quieter), at a vent near top, to draw hot air out. Put in a vent at the bottom to stimulate airflow throughout the cab.
Check out my completed projects!


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Re: Vector-gasm... Cosmic Chasm!
« Reply #43 on: March 18, 2023, 12:07:38 am »
I had forgotten that the way I built the cabinet there is a huge vent across the front toe kick panel.
If I just drill a hole in the top panel and put a fan sucking out on it that should help immensely.

I might actually shift the deflection board over to the side of the cabinet and put a fan underneath it pushing air through the slots and up.

The pair of fans I ordered came in today so we'll see how soon I can get to this.

I have a roll of magnetic tape and a few small cake neodymium magnets so we'll see what I have learned after a little experimentation.
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

Xiaou2

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Re: Vector-gasm... Cosmic Chasm!
« Reply #44 on: March 19, 2023, 06:02:53 am »
Fans do not "Suck" anywhere near as good as they "Blow".

 You can test this for yourself.. with a standard box fan.   Place the fan facing away from you... and see if you can tell any difference.
Then point it towards you.

 The thing about "Air" is that it behaves like a Fluid... and Fluids flow and swirl, in very chaotic directions.

 All PC Servers, use Forced Air, to blow through them...  as do standard CPU coolers.  Anyone that has tried to reverse
their CPU cooler fan to "Suck" the heat away... has typically ended up having their CPU permanently Fried.
(or severely heat "Throttled".. until it completely overheats and auto-shuts off)

 Most Arcade Cabinets have top vents for rising hot air to escape.  And many even have Fans that are mounted towards the top of
the cab, that push out of the top-rear of the cabinet.

 Additionally, some cabinets have Inlet fans at the bottom... to pull cooler air into the cab.. with the top fans blowing hot air out
of the cabinet.

* Actually, the fans at the bottom, are probably more to cool the Power Supply / Transformer units, that typically sit down there.

 I highly recommend using a good cooling fan, blowing directly across your heat-sinks.  The cooling will be Far more effective, and
will greatly extend the lifespan of the electronic components.
« Last Edit: March 19, 2023, 06:06:08 am by Xiaou2 »

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Re: Vector-gasm... Cosmic Chasm!
« Reply #45 on: March 19, 2023, 05:34:35 pm »
Yeah, I'm not in the mood to build a manifold for a fan to draw through for the "suck" concept to be functional.  I have space to arrange well for the "blow"air flow plan.
I'm going to not fight physics so I'll mount the deflection board on its side so that the fan will be blowing up through the cooling fins- and then have a fan on the top panel drawing air out of the cabinet.
There is a 2" deep slot that is the width of the cabinet in front so there will be plenty of air flow available.

I thought I would be doing this over the weekend but Tyler finally got motivated enough to clean his room so I would help him put together this pile of this gaming rig components for him, which I've been staring at since... Christmas!?
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

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Re: Vector-gasm... Cosmic Chasm!
« Reply #46 on: March 19, 2023, 10:15:53 pm »
 
Fans do not "Suck" anywhere near as good as they "Blow".

 You can test this for yourself.. with a standard box fan.   Place the fan facing away from you... and see if you can tell any difference.
Then point it towards you.


Steve.  Please sit and rethink about this for a moment.




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Re: Vector-gasm... Cosmic Chasm!
« Reply #47 on: March 19, 2023, 11:38:34 pm »
This is the funniest thing I have read in a while!
Fans do not "Suck" anywhere near as good as they "Blow".

 You can test this for yourself.. with a standard box fan.   Place the fan facing away from you... and see if you can tell any difference.
Then point it towards you.


Steve.  Please sit and rethink about this for a moment.




Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

abispac

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Re: Vector-gasm... Cosmic Chasm!
« Reply #48 on: March 23, 2023, 09:58:55 am »
Bobby13, i love this thing and the most important part is the making of the monitor with consumer parts and the fact you can hook a pi to output vectors, have you thinked on making a separated topic on how to build a vector monitor so you can share that knowledge?

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Re: Vector-gasm... Cosmic Chasm!
« Reply #49 on: March 23, 2023, 07:03:00 pm »
I thought that's what I was doing here?
 :lol

I haven't been able to update anything on the monitor itself here for a while because first I was waiting for parts and now I'm waiting for free time!

Hopefully I can get back at it over the coming week.
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

Edgecrusher

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Re: Vector-gasm... Cosmic Chasm!
« Reply #50 on: March 23, 2023, 09:08:29 pm »
I thought that's what I was doing here?
 :lol

I haven't been able to update anything on the monitor itself here for a while because first I was waiting for parts and now I'm waiting for free time!

Hopefully I can get back at it over the coming week.

Important thing is your project is valuable to some people. I've been wanting to thank you for posting this myself. I'm not as well versed on anything related to video games or the machines they ran in. I just know what I loved when I played them back in the '80's and now that I'm an old guy and an electrician I'm realizing these are really challenging projects. I have to admit my ignorance, before this post I didn't even realize games like Tempest (my all time favorite alongside Star Wars) required a special monitor to display correctly. I've been collecting quite a few TV's the last couple years and my next cabinet I intended to build was a Tempest cabinet. I'm gonna have to study your build closely because I want it to be as badass as possible. Thank you and keep up the hard work, .....when you get the time.

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Re: Vector-gasm... Cosmic Chasm!
« Reply #51 on: March 23, 2023, 09:22:57 pm »
I have an older 19" from before remote controls which I haven't gotten into yet but I've been wondering if I can RGB mod. This just may be the answer...

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Re: Vector-gasm... Cosmic Chasm!
« Reply #52 on: March 23, 2023, 09:27:11 pm »
There's a lot of content in this thread so maybe I missed it; but I was gonna suggest, if you intend to make this a how to, maybe start with a list of all the components required and maybe a general cost you expect for everything...so people know what their getting into

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Re: Vector-gasm... Cosmic Chasm!
« Reply #53 on: March 23, 2023, 10:08:35 pm »
There's a lot of content in this thread so maybe I missed it; but I was gonna suggest, if you intend to make this a how to, maybe start with a list of all the components required and maybe a general cost you expect for everything...so people know what their getting into
Yeah mr bobby13 ,  i though about this too, because maybe is my bad english, but so far i understand this, you need a consumer set that its close to a certain levels in the yo, then you need to rewire the yoke, may i ask how?, then you need to buy some parts, like a vectorchassis, and the interface betwen the monitro and the pi, witch is a usb something right? sounds easy enough, the hardest part would be rewire the yoke?

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Re: Vector-gasm... Cosmic Chasm!
« Reply #54 on: March 24, 2023, 12:26:19 am »
Forgive me how scattered some of this is still.
I am really only executing on other people's work, some of which is documented elsewhere and some which isn't really- and not in thorough definitive detail for any of it really.

So that I'm not posting erroneous or vague info I don't want to list anything as a how to until I REALLY know that what I am posting works- like what I did with the Pi setup portion in this thread thus far.

I'm getting there with this project so I will begin a specific 'build yourself a monitor part' when I learn all I can about how to screw it up first.

I'm close with the monitor (with three separate ones actually- all using different components even) but when I get there you will know if you are checking back here because I will do a step by step on that too.

If enough people care the info can get recompiled in a more flowy fashion later I suppose.

This thread just looks like how my mind works as I run through engineering on the fly I suppose.
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

abispac

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Re: Vector-gasm... Cosmic Chasm!
« Reply #55 on: March 24, 2023, 09:49:58 am »
Thank you kind, will be keeping an eye on this one.

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Re: Vector-gasm... Cosmic Chasm!
« Reply #56 on: March 24, 2023, 02:23:39 pm »
Cool.
I don't want to come off as being critical at all. If anyone understands having ten thousand things going on at one time and not having enough time for even a fraction of them, it would be me.

I'll wait patiently. Well, I'll try... Maybe I can even study up and eventually be of some help at some point. who knows.

 :cheers:

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Re: Vector-gasm... Cosmic Chasm!
« Reply #57 on: March 24, 2023, 05:51:22 pm »
Not at all!
Criticism is welcome when people have some that is useful.

If you really want to build yourself a vector machine then posts #14, 22, 32, and 33 are the real meat of this thread.

If you read those, give a good look to the docs and videos I link to, and buy yourself the parts then you are most of the way there.

I spent a free morning rearranging components in this cabinet to suit some good cooling so I will update this again when I can get a chance here soon.
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

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Re: Vector-gasm... Cosmic Chasm!
« Reply #58 on: March 28, 2023, 08:22:15 pm »
Trying again.

Had a chance to get back to the machine and turn it on after rearranging things finally.
I pulled most of the parts out first to have a good uncluttered think on it.
The result is...



Wound up leaving the power supplies, DVG, and the Pi in the same places and swapped the HV unit and deflection board positions.

Makes for a better cooling layout, keeps those parts as far away from each other and the tube as possible and the parts still remain on the shelf I made for the stuff.

It also allowed me to turn the deflection board on its side and possibly gain a little in velocity as regards the heat being evacuated through the cooling fins.

The 120VAC fan I got is kind of noisy (and may get replaced if it is distracting once I have the bezel area built and in) but it certainly does what I wanted it to.
I drilled a hole in the shelf to allow the fan to draw from wherever it likes and gave it a good angle to shoot into but still across the heatsink.
The other bonus is I got to add a block of ply underneath the heatsink to carry the weight of it on its own.

Prior to component rearrangement and install of the fan I was seeing 185 F on the heat sink next to one of the transistors.

In that same spot the temp is now down to 95 F.
I expected a good drop in temp, but wasn't expecting one that dramatic.

Certainly worth the effort!
I'm stoked.

Audio amp should be here by the weekend I think and after that is done then it's time to start on the bezel extravaganza.

Still haven't decided if I care enough to bother sanding the cabinet again and getting a more proper coat of flatter finish paint on the outside.
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

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Re: Vector-gasm... Cosmic Chasm!
« Reply #59 on: March 29, 2023, 02:08:00 am »
Bobby, just read through your entire thread for a second time! Starting to make more sense now (kinda!  :lol ).

I'm feeling inspired. So, looks like I'll have to make room for my own vector project, as soon as I can make room in my shed and life, while people like you are focused on it and able to help. Wish I could work on such things as fast as you do.

I messaged Barry, a long time ago, asking to be put on his list for the vector kits. Looks like I'd better dust-off my FB account and try him again.

Though I do understand the reasons, still finding it bizarre that you need 2 x 24v PSUs for both positive and negative voltages. Ah well, whatever works :)

Love your work, neat n tidy, and my only vaguely helpful suggestion for today is that I think you could put the USB_DVG thing on the other side - that way you won't have to run that VGA cable across the back, and it won't get in your way when you are fiddling around inside.
Check out my completed projects!


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Re: Vector-gasm... Cosmic Chasm!
« Reply #60 on: March 29, 2023, 02:47:09 am »
One time I bought some AC fans from a Surplus place.  They were like 1.5" thick, with 3 large blades.  I believe they came out of
those ancient + massive  HP Laserjet printers.   They were loud AF...  but they also moved about 30 times as much air as any PC
fan that Id ever owned.  I shoved a carrot into the blades to see how bad it might be to run them without the Grills... and it had
the power to actually chop the carrot clean, like a food processor.

 If you want a quieter fan.. you would probably better to use a DC based PC fan.  You can use one of the larger diameter fans,
for even less noise + greater overall air movement.


 Most arcades were noisy enough, especially when you are playing at a decent volume.. that you would never hear
the cooling fans that were inside of them.

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Re: Vector-gasm... Cosmic Chasm!
« Reply #61 on: March 29, 2023, 06:27:16 am »
Some fans are quieter than others. Sometimes they just get a little old/worn, and sometimes they get a bit dry and just need a little lubrication.

You could always lifting up an edge of the sticker in the middle, and putting a few drops of fine motor oil into the sleeve/bearings.
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Re: Vector-gasm... Cosmic Chasm!
« Reply #62 on: March 29, 2023, 11:59:36 pm »
This thing is new and all metal and the blades are really moving some air so I imagine what I am hearing is just blade noise.

I does kind of remind me of a model plane I had when I was 10!

Suspect that it will get a bit quieter with time and I am going to get to install the audio system tonight it appears and then maybe get going on the bezel shroud by this weekend so it may be a non issue anyway.

Get building everybody!
I think I'm catching up to some of you!
 :cheers:
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

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Re: Vector-gasm... Cosmic Chasm!
« Reply #63 on: March 30, 2023, 01:14:28 am »
You can do a lot with fans. Always easy to swap in a different fan that might be quieter/larger/flashier whatever.

If you go DC for the fan, you can throttle the speed by installing a resistor (appropriately rated) on the active input line. This both limits current and creates a simple voltage divider (in this case the other "resistor" is the impedance in the fan's coils). You can (for example, with a 12v fan) throttle 12v input down to around ~7v and the fan will still turn, just slower (and therefore quieter).

The trick is getting the right resistor value. I suggest good-old trial-and-error, because every fan will have different impedance characteristics anyway. Also, the coil's impedance (R) goes up as current increases, so it's R value will decrease as the resistor value increases. Because of this, you can't measure the coil impedance directly with a DMM (AFAIK), but once you install a "test" resistor you can easily calculate the impedance value by using the known or observable values (voltages, resistor) and applying normal voltage divider rules (or one of those online calculators if you are lazy like me).

You could even use a potentiometer (pot), at least until you know what resistor value you want. I guess the same logic applies to AC fans, but doing this kinda thing with DC feels safer.

Technically it is also possible to use the fan's third input (if it has one) to throttle fan speed, but this requires a logic controller as it works by switching the fan on/off really fast. You could probably control fan speed by using the Pi itself (but I don't know very little Pi lore), or perhaps an Arduino, but (ironically) that all sounds much more complicated to me.

Sorry for the long post, hope it is relevant ;)
Check out my completed projects!


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Re: Vector-gasm... Cosmic Chasm!
« Reply #64 on: March 30, 2023, 12:28:54 pm »
If you want to get ambitious, a honeycomb composite "cowling" or shroud can be made to go around the fan and heatsink along with ducting to redirect the blade noise to the bottom of the cabinet.  basically the same thing turbine engines have that makes them louder front and back versus side-to-side.

Assuming it's like my 386 PC I installed an AC fan on 'cause it's what I had,  ;D it's blade noise.

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Re: Vector-gasm... Cosmic Chasm!
« Reply #65 on: March 30, 2023, 08:52:36 pm »
My "stufff some foam around somewhere" plan is beginning to feel a bit provincial at this point.
 ;D

Once I had the cheap little 2.1 channel amp I got in place and fired it up the fan noise nearly disappeared from a player's perspective.
By the time I get the bezel shroud done the noise will be a non-issue.

Which is good, because there are enough issues yet still as it is!

I actually had to shift layout here AGAIN because once I finally got to play the silly thing with everything powered up in place it was alarming to see how much vibration in the screen image the fan was producing somehow.

I thought it might be a power supply ripple type of issue and powered the fan from outside the cabinet, tried with an isolation transformer too and still had major image shake.
That freakin 120VAC fan is generating quite the emf to get spinning apparently.

Maybe next time it is worth getting a 12VDC supply and fan and maybe there won't be a 2000mg of caffeine kind of jitter to the image with the fan closer to the tube.

I dropped the shelf and deflection board down a few inches- which of course necessitated dropping the power supply shelf to the floor, which also made it necessary to shift that two gang junction box over alao.
And move the degauss board.
 :banghead:

At least the effort netted the desired result.

Next is the craziness that was going on in the vector drawing- which I actually figured out.
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

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Re: Vector-gasm... Cosmic Chasm!
« Reply #66 on: March 30, 2023, 11:20:43 pm »
I actually had to shift layout here AGAIN because once I finally got to play the silly thing with everything powered up in place it was alarming to see how much vibration in the screen image the fan was producing somehow.

I thought it might be a power supply ripple type of issue and powered the fan from outside the cabinet, tried with an isolation transformer too and still had major image shake.
That freakin 120VAC fan is generating quite the emf to get spinning apparently.

Maybe next time it is worth getting a 12VDC supply and fan and maybe there won't be a 2000mg of caffeine kind of jitter to the image with the fan closer to the tube.

Unsurprisingly, you are correct! Fans, like pretty much every electric motor, work by creating a fast-switching electromagnetic field. Given how close the fan is (was?) to the CRT neck, some direct interference is not surprising :)

Would be interesting to see if the "jitters" disappear as you simply move the fan further away from the neck.

That, and yeah, there could very well be an EMF effect from the AC motor causing electrical interference on the mains line as well. Iso transformer on monitor won't necessarily stop this. However, a line filter (to isolate the fan EMF) may help, is what it is designed to do. Line filters are cheap, but so are DC fans.

Oh oops, you don't have a 12VDC power supply! Not to worry, there are plenty of 24v fans available to suit your needs, and you already have oodles of 24v power. I just did a quick search and this popped up for < $10:

GDSTIME 80mm x 80mm x 25mm 24V Brushless DC Cooling Fan
https://www.amazon.com/GDSTIME-80mm-25mm-Brushless-Cooling/dp/B00N1Y3T9G

It doesn't advertise itself as "quiet", but read the reviews, it seems to be pretty quiet. It even comes with a protective grill and nuts/bolts.
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bobbyb13

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Re: Vector-gasm... Cosmic Chasm!
« Reply #67 on: March 31, 2023, 04:01:37 am »
I was afraid to connect anything else to the power suppllies feeding the deflection board or I would have gone exactly that route with a 24VDC fan!
Been terrified to blow something up here all along really.

And it isn't even so much the $$ but the fact that these kits are still kind of in the unobtanium kind of realm still currently.
I waited over a year for a USB-DVG unit (even after I had paid for it) and I have been on the wait list for an Amplifone repro kit for longer than that at this point.

Not to fault any of the crew involved in making these things mind you, they all have busy (and sometimes rather complicated it appears?!) lives of their own to lead, but when you are obsessed with this stuff like I am it is unnerving to wait so long- and to sometimes think it is never going to happen anyway.

I had experimented with the fan positioning and orientation before I decided on the current layout.
Literally just waved it around in the cabinet with it plugged in and running to see how it affected the image on the monitor.

Even tried to Faraday cage the stupid thing in its original spot to no avail.

I found how close I could get it to the tube without any drama with the hot and floating technique and then mounted it another inch further away than that even.
And so we have composition #3.



Hopefully the only thing that moves from here is the audio amp, so it can be played with through the eventual coin door.

With the thousand bpm shake managed it was time to address the broken vector weirdness which randomly appeared once I had nearly everything else sorted out.

Full disclosure:
I have tried three different rewound yokes on this thing so far.
They have very similar values in terms of resistance but produce different quality images for sure.

One was the original to the tube.
Sadly I pulled a bunch of correction strips off of it before I realized that maybe they should stay and I have had major convergence issues with that one since.
Maybe some day I can get it back to good, but dialing in a yoke is pretty heady stuff that I still know almost nothing about yet.

Many of the numerous documents I have found on purity and convergence tuning speak as if it is a very scientific and systematic process that is not difficult.
Ha-
Of all the esoteric themes in this hobby yoke gymnastics are easily the most arcane.

Another fellow CRT maniac here (who is far beyond me in knowledge and skill) has a bucket of old yokes from tubes he has scavenged and last I was at his house we dug through it with an inductance meter and found a few with promising values- so I rewound one of those.
The mounting collar is kinda beat up so it is hard to get the thing to stay seated really well but I tried it anyway.
It too produces a fairly un-converged image.

The kit that I bought second hand from a gent in Canada (although I don't believe it was used- maybe not even tested out) came with a rewound yoke- and that is what is currently (haha) on the tube.
The convergence still gets a bit wonky as you get to the outer perimeter of the screen, but during game play there is really no discernable issue thankfully.

And so even as good as I could get this last yoke to look there was still some weird stuff going on with the image on screen.
Such as....


What was really weird to me at first about these bizarre tails to some of the images is that they don't all head in the same direction or have any consistency to them at all really, but after I thought about it this makes sense.

The image is being drawn by the guns which are aimed at the center of the screen and then the beam is deflected to the proper position and then lit up when it is in the right spot, but it is not as if the beams need to draw one image, go back to center, and then get bent around again to draw the next.

If you crank up the screen adjustment on the HV unit (lower dial on the 'flyback transformer'- which it isn't in this case- even if it looks like one to you) you can actually see the path of the beams as they are flying around the screen- and then these weird tails on images make sense.
It is a pretty impressive sight really.



What I was looking at is the beam getting lit up ('Z' axis voltage in Atari-speak) before it actually got to the location it was supposed to be drawing something.
So the deflection board is (very!) slightly slower in bending the beam than it is in lighting it up- and hence the timing being off just that little bit makes for a line where you don't want one.

Enter Slew Rate.

The USB-DVG has a menu all on its own, accessed by a button on the board itself.
The first thing you see when you access it is this.



As my world expands here I am starting to figure out what all this crap is now.

The first line is an obvious one, as it lists all of the original vector monitors here (G-08, WG6100, Amplifone, etc...) and selecting one automatically loads the settings below for what works best with a healthy original monitor.
I selected the Amplifone one for this to begin with since that is what Barry cloned here with this kit but this is where the nuances of this hole thing begin to get tricky.

Note that I said that those default settings are for a "healthy original monitor."
My boards and tube are fine BUT, this is NOT an original yoke- and this is where it starts getting sticky and this is all finally making sense to me now.

My rewound yoke does not act EXACTLY like an original Amplifone one because the outer yoke coils, although having been rewound to get close, are still a slightly different inductance/resistance than original (so are the inner ones for that matter) and therefore they DO NOT deflect at exactly the same rate as original ones do.
Cranking up the Slew Rate allows the beam to get knocked around faster (it allows a faster rate of voltage change to the deflection to more precise) and therefore get to where it is supposed to be in time for the 'Z' axis to get lit up at the right time and draw the images properly.

Neat, yeah?!

Even just a few ticks of bumping up the rates yielded great results.
Behold!



I'm still trying to figure out exactly how the "Jump Rate" and "Beam Delay" settings affect what I am seeing.

Anyone who knows more about electronics here please chime in!
« Last Edit: March 31, 2023, 04:35:08 am by bobbyb13 »
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

pbj

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Re: Vector-gasm... Cosmic Chasm!
« Reply #68 on: March 31, 2023, 04:26:35 am »
Looks fine to me, vector games were always slightly screwy looking.  Stop being picky and move along.


bobbyb13

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Re: Vector-gasm... Cosmic Chasm!
« Reply #69 on: March 31, 2023, 04:47:16 am »
You are absolutely right of course pbj, but it is fun to see how all this crap works and figure out how to get it to look really good.
There is still some pulsing in the menus and other weird stuff that I will probably never sort out.
What is excellent is that none of the stuff that was really distracting (like the cute little pigtails) ever seem to occur when the games are running.

The more I learn about it the more amazed I am that somebody could figure this ---steaming pile of meadow muffin--- out to begin with.
And then the speed at which all this stuff occurs will forever blow my mind.

I'm stoked really.
This thing plays Cosmic Chasm, Tempest, and Tac/Scan well and it looks awesome.

What is nice about this really is that the next vector machine will be considerably less of a pain in the ass!
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

Zebidee

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Re: Vector-gasm... Cosmic Chasm!
« Reply #70 on: March 31, 2023, 05:00:54 am »
I quite liked how the settings screen looked, before you adjusted the slew rate. That font be crazy man!

Thanks for the pic showing the beam paths - a penny just dropped, somewhere in my brain. Now I know exactly why they are called "vector" monitors.
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bobbyb13

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Re: Vector-gasm... Cosmic Chasm!
« Reply #71 on: April 04, 2023, 12:42:39 am »
Vector monitors are quite cool things.
I'm looking forward to building a few more machines that use them now.

Encouraged to see that even with the cabinet rearragnement to accomodate the fan's crazy emf I still have great heat sink temps.



Even with that massive block of aluminum I think the fan is a must to not have to worry about roasting components on the deflection board over time.
So after I moved everything else around to accomodate the audio (I built a little box for the woofer I had for it- just for fun) and moved the shelf I accidentally put in my own way for getting the kick panel off I think I have finally arrived at the final cut.

Time to add a little screen to the bottom vent slot and then pop a hole somwhere in the top (or maybe the backside transom panel?) to finalize the cooling flow route.

At this point it is really fun to play and produces an image that is damn sharp and has no issues during gameplay at least.

Winning!



Next is the bezel and shroud.
Still on the fence about dropping the screen angle back to my best guess at what was original before I get started on that last piece.
Nothing to gain from it for me but it would be cool to be able to reproduce something with dimensions that would be useful to others in the future.

Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

Zebidee

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Re: Vector-gasm... Cosmic Chasm!
« Reply #72 on: April 04, 2023, 03:12:58 am »
Bobby, I think you've already made a lot of people happy, just by posting this stuff.

So angle the screen however you want, make yourself happy :D

Very damn nice indeed, I am feeling inspired.
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Mike A

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Re: Vector-gasm... Cosmic Chasm!
« Reply #73 on: April 04, 2023, 06:21:12 am »
You went through all of this trouble.

Get it right.

I know that you are itching to do that anyways.

I know a guy who has a Cosmic Chasm.

I will reach out and see if he can give me an angle measurement.

bobbyb13

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Re: Vector-gasm... Cosmic Chasm!
« Reply #74 on: April 04, 2023, 01:48:03 pm »
That would be outstanding Mike.
I can make a few other people happy too if I'm able to make a 1:1 repro of that thing.

You went through all of this trouble.

Get it right.

I know that you are itching to do that anyways.

I know a guy who has a Cosmic Chasm.

I will reach out and see if he can give me an angle measurement.
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

Zebidee

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Re: Vector-gasm... Cosmic Chasm!
« Reply #75 on: April 04, 2023, 04:16:45 pm »
I can make a few other people happy too if I'm able to make a 1:1 repro of that thing.

This is why I keep coming back here - people helping other people with little things, so the bigger things turn out right.
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Re: Vector-gasm... Cosmic Chasm!
« Reply #76 on: April 04, 2023, 04:54:48 pm »
Bobby,

Excellent work all around.  One thing to note is, you may be having some trouble with the yoke and convergence (particularly the further you are from the center of the screen) as you have a 51cm (20 inch) tube.  Not to send you down a rabbit hole but the deflection angle of the ferrite cores would most likely be slightly off compared to a standard 48cm (19inch) tube.  If it were me Id work with the yoke that came with it as it was designed for that tube size.

bobbyb13

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Re: Vector-gasm... Cosmic Chasm!
« Reply #77 on: April 04, 2023, 08:27:58 pm »
Absolutely correct Scott.
After all of my agonizing about using the original yoke the great irony is the one that's on it right now and looks the best is from a different tube, and I don't know exactly which tube even.
It's possible that in the future I may decide that it needs to be perfect but at this point it looks so good that this one may just remain as it is and what I have learned here will just be applied to the next ones.

Of course had I seen your caveat about not messing with the other magnets on the yoke in time to begin with I probably wouldn't even be in this spot!
 :cheers:

There are still a few details for me to learn about how all this vector hardware works and how it can be adjusted but as a first run of sorting it out I can call this machine a success at least.

This thread may go quiet for a bit while I hope for bezel and shroud details to materialize (thank you again Mike for the offer of a shot at it.)
As this go round has a fairly exhaustive breakdown of getting the Pi and DVG as well as the controls working I may just leave this thread as a reference for that and use the next build for more monitor detail.

It's been a fun journey so far no matter what!
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.

Mike A

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Re: Vector-gasm... Cosmic Chasm!
« Reply #78 on: April 04, 2023, 10:12:12 pm »
I put out a request to go see the cab and measure anything you want me to.

bobbyb13

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Re: Vector-gasm... Cosmic Chasm!
« Reply #79 on: April 04, 2023, 10:28:11 pm »
I put out a request to go see the cab and measure anything you want me to.

You rock
As usual
 :cheers:
Relax, all right? My old man is a television repairman, he's got this ultimate set of tools! I can fix it.