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Electrical connection questions


Mick80

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Hi all,

 

I'm in the final stages of connecting up my new Sharp Image SI727 chassis and have two connections left to make that have me scratching my head. I've spent a couple of days searching for the answers on various forums and the internet generally to no avail.

 

The first is the yoke connector wires to the chassis are split into four different connectors, I've measured their resistance values so I know which pairs are vertical and horizontal but in which order should they be connected to the new chassis if the chassis doesn't have any helpful markings on it (the old one had H H V V)?

 

20171023_110416.jpg

 

The other question is in regard to the power supply for the chassis- it can take 240v AC directly so I've connected the chassis' two power supply wires to the incoming 240v active wires via a connector (they weren't marked so I assume that they can be connected either way around?). This leaves the question of what should I attach the 240V ground wire to?

 

I read in the arcade machine restoration Wiki that all components should be attached to the flat ground strap that runs under the components in the cab, but the previous chassis wasn't connected to this (it had the 240v ground wire connected to the isolation transformer). As the chassis is only mounted on a plywood shelf, is it OK to connect the ground wire under one of the screws holding the chassis down to the plywood or should it be run to the flat ground strap?

 

20171023_112703.jpg

 

Any help would be greatly appreciated.

 

Cheers

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Don't know where you got the chassis from but beware some chassis say 220-240v but may be setup for 100v

If connected to mains they will let out the magic smoke

 

It's a Jomac chassis- I've been thinking of keeping it running off the transformer at 110v just to be safe.

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It's a Jomac chassis- I've been thinking of keeping it running off the transformer at 110v just to be safe.

 

That chassis from Joey is free voltage, it will accept 110-240 no issues. It's your call what to use as it usually doesn't make a difference. The transformer can sometimes cause monitor wobble due to interference if it sits too close to the tube, but that usually only happens in small cocktail cabs.

 

As I said in my PM, the red/blue yoke connectors are usually spaced further apart as the yoke connector is keyed to make this happen so you can't plug them in the wrong way. Sadly, as your connector is broken into 4 pieces (who does this?) you need to be careful and ensure that you hook up red/blue to the 2 yoke pins on the chassis that are spaced further apart.

 

Maybe an expert can chime in on this. On all the monitors I have setup, the red/blue plug always goes onto the wider spaced pins. As can be seen in this image.

 

http://www.bitsmarter.com/wordpress/wp-content/uploads/2010/01/yoke_flip2.jpg

 

I've never seen it any other way, but that doesn't mean it doesn't happen at all. You want to be 100% sure that you have those paired wires plugged into the right location before powering up the monitor.

 

I won't chime in at all on the 240V question, simply as I am not confident enough with anything 240V to provide an answer.

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As the chassis is only mounted on a plywood shelf, is it OK to connect the ground wire under one of the screws holding the chassis down to the plywood or should it be run to the flat ground strap?

 

I don't reckon that earth wire will make a rat's, but i 'm not actually sure. They're often there to help with certain interference problems on cheap chassis, which this may not be and so may not have. But talk to Joey.

 

As for the yoke connector, the two individual sections, HH and VV, are continuous H-to-H and V-to-V but never H-to-V. The red wire is definitely for the horizontal coil, so put one of of your multimeter leads on it and find the other wire it connects to - should be the blue one. You'll be expecting to read about 2ohms, though anything from 1 to about 3 is fine, depending on the size of the tube. The other two plugs are for the vertical coil, and will show anywhere between 10 and 50ohms between them. This is all without the yoke connectors plugged in.

 

On the chassis the horizontal coil is the pair of pins with the wider spacing - the red lead normally goes on one end, on the most isolated pin of the four, with the other (normally blue) horizontal wire going next along.

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I don't reckon that earth wire will make a rat's, but i 'm not actually sure. They're often there to help with certain interference problems on cheap chassis, which this may not be and so may not have. But talk to Joey.

 

As for the yoke connector, the two individual sections, HH and VV, are continuous H-to-H and V-to-V but never H-to-V. The red wire is definitely for the horizontal coil, so put one of of your multimeter leads on it and find the other wire it connects to - should be the blue one. You'll be expecting to read about 2ohms, though anything from 1 to about 3 is fine, depending on the size of the tube. The other two plugs are for the vertical coil, and will show anywhere between 10 and 50ohms between them. This is all without the yoke connectors plugged in.

 

On the chassis the horizontal coil is the pair of pins with the wider spacing - the red lead normally goes on one end, on the most isolated pin of the four, with the other (normally blue) horizontal wire going next along.

 

Thanks Namastepat and Buttersoft

 

You're both saying the same thing in regard to the position of the horizontal and vertical pairs so I'm going to give it a try. I'd previously identified the horizontals and verticals with the multimeter so I'm confident that the colours are correct.

 

I've probably bothered Joey enough with this one- he referred me to this thread https://www.aussiearcade.com/showthread.php/41825-Jomac-Custom-Universal-Dual-Res-Chassis-Installation but it didn't cover all the bases unfortunately.

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I just pulled apart my Panasonic 25" TV to have a look what colour order it is wired in.

 

I was really hoping it was going to be identical to what you blokes were saying but it's not.

 

It is coloured: Red (thickest wire and most isolated)

big gap then

Yellow

Brown

Blue (at the other end)

 

In my arcade cabinet the end of the yoke connector that I didn't touch that remained connected at the yoke is coloured:

 

Red

Big gap

Yellow

Brown

Blue

 

Just like in the Panasonic TV mentioned above.

 

Also the chassis end of that wiring connector matches that order when the broken edges are compared.

 

So if I connect it to the chassis in this colour order, I'm still blind as to which way to connect it around. It could go one way, or 180 deg the other way and the colours conflict with what you guys are saying.

 

There must be a few things I'm missing here!:o

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So I've re-measured the resistance of the wires with the chassis end of the wires disconnected and as before I got:

 

Red and Blue pair: 2.2 ohms

 

Brown and Yellow pair: 8.6 ohms

 

Connecting between Red and Brown or any other combination gave no readings. So red and blue must be horizontal.

 

What has been confusing the hell out of me is that everyone is saying the horizontals should be next to one another on the yoke connection or on the plug, but in this case their at opposite ends of the plug.

 

On the previous crappy chassis I removed the pins were ordered H H V V. On the sharp image (Jomac universal) they're not numbered/identified at all. So I'm just going to assume that for some reason Panasonic put them in a strange order on their yokes and that's why the plugs were cut into 4 separate parts back in the day.

 

Does that sound feasible?

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What has been confusing the hell out of me is that everyone is saying the horizontals should be next to one another on the yoke connection or on the plug, but in this case their at opposite ends of the plug.

 

On the previous crappy chassis I removed the pins were ordered H H V V. On the sharp image (Jomac universal) they're not numbered/identified at all. So I'm just going to assume that for some reason Panasonic put them in a strange order on their yokes and that's why the plugs were cut into 4 separate parts back in the day.

 

Does that sound feasible?

 

 

More likely is that the pins were in the same order, just spaced differently. I've seen that same larger connector with 5 slots (1 of which is empty, normally the one between red and blue). And there are the TV's that use different, thinner pins/connectors too. Do the 4 broken parts of the connector fit together in any order?

 

I've seen a blue wire going to the vertical coil, but it's not common. There are a few combinations out there, it seems. But i've only ever seen red for horizontal going to the most isolated pin.

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This is how the plug was with the game running

 

- - - Updated - - -

 

More likely is that the pins were in the same order, just spaced differently. I've seen that same larger connector with 5 slots (1 of which is empty, normally the one between red and blue). And there are the TV's that use different, thinner pins/connectors too. Do the 4 broken parts of the connector fit together in any order?

 

I've seen a blue wire going to the vertical coil, but it's not common. There are a few combinations out there, it seems. But i've only ever seen red for horizontal going to the most isolated pin.

 

The broken connectors show a smooth edge on the blue and red wires, just like the unbroken yoke end. This arrangement is identical to both ends of the plug in the Panasonic TV I opened this afternoon (the tube in the arcade is Panasonic too BTW)

20171024_204741.jpg

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I've never seen a connector on that end! How about that. Very handy.

 

I would guess that while the tube connector end looks like that, the chassis end was red---blue-grey-yellow. That's the only way that makes the lead reversible. This is the tube you post the resistances for, yes?

 

EDIT: ok, let me edit this in light of your edit...

 

So, if you're measuring 2ohms between the red and blue wires, those are the horizontal coil. The 8.6ohm reading for the yellow and grey make them the vertical coil.

 

Just make sure which pin is which on the chassis. It's normally H-HVV, in fact i've never seen it any other way, and now i'm going to have to double check a few things i thought i knew :)

 

Check with Joey, i guess? I'd hate to tell you which pin was which and get it wrong.

 

EDIT2: It would make sense for the plug to be broken if a chassis this tube was connected to had the yoke connector pins in the usual order. You're saying you have a TV that at the chassis end has the horizontal coil wired to the most isolated pin, and then the pin right at the other end of the connector, with two more pins wired in the center, is that right? Can you verify this with your multimeter?

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I've never seen a connector on that end! How about that. Very handy.

 

I would guess that while the tube connector end looks like that, the chassis end was red---blue-grey-yellow. That's the only way that makes the lead reversible. This is the tube you post the resistances for, yes?

 

EDIT: ok, let me edit this in light of your edit...

 

Yes the picture above is the tube in the cabinet that I gave the resistance values for.

 

Panasonic must have had rogue electrical engineers???

 

- - - Updated - - -

 

I've never seen a connector on that end! How about that. Very handy.

 

I would guess that while the tube connector end looks like that, the chassis end was red---blue-grey-yellow. That's the only way that makes the lead reversible. This is the tube you post the resistances for, yes?

 

EDIT: ok, let me edit this in light of your edit...

 

So, if you're measuring 2ohms between the red and blue wires, those are the horizontal coil. The 8.6ohm reading for the yellow and grey make them the vertical coil.

 

Just make sure which pin is which on the chassis. It's normally H-HVV, in fact i've never seen it any other way, and now i'm going to have to double check a few things i thought i knew :)

 

Check with Joey, i guess? I'd hate to tell you which pin was which and get it wrong.

 

EDIT2: It would make sense for the plug to be broken if a chassis this tube was connected to had the yoke connector pins in the usual order. You're saying you have a TV with the horizontal coil wired into the most isolated pin, and then the pin right at the other end of the connector, with two more pins wired in the center is that right? Can you verify this with your multimeter?

 

The picture above, of the unbroken connector, is exactly the same order (and the same length/manufacturer of plug) as the one that is ALSO in my Panasonic 25" TV which is my backup for if this one dies.

 

The chassis that I'm throwing away has the normal H H V V order, and therefore the tech had to take his hacksaw and cut the chassis end of the connector into 4 pieces so he could connect in the normal Red--Blue-yellow-brown order.

 

- - - Updated - - -

 

I've never seen a connector on that end! How about that. Very handy.

 

I would guess that while the tube connector end looks like that, the chassis end was red---blue-grey-yellow. That's the only way that makes the lead reversible. This is the tube you post the resistances for, yes?

 

EDIT: ok, let me edit this in light of your edit...

 

So, if you're measuring 2ohms between the red and blue wires, those are the horizontal coil. The 8.6ohm reading for the yellow and grey make them the vertical coil.

 

Just make sure which pin is which on the chassis. It's normally H-HVV, in fact i've never seen it any other way, and now i'm going to have to double check a few things i thought i knew :)

 

Check with Joey, i guess? I'd hate to tell you which pin was which and get it wrong.

 

EDIT2: It would make sense for the plug to be broken if a chassis this tube was connected to had the yoke connector pins in the usual order. You're saying you have a TV that at the chassis end has the horizontal coil wired to the most isolated pin, and then the pin right at the other end of the connector, with two more pins wired in the center, is that right? Can you verify this with your multimeter?

 

I'll have to take that TV apart tomorrow, discharge it and check with the multimeter. But yes, I do believe Panasonic have gone Horizontal(Red)---Vertical-Vertical-Horizontal

 

- - - Updated - - -

 

This manufacturer just crossed things over???????

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Ok, so I am a total noob when it comes to monitor issues but a few things that I have seen online for this monitor suggest to me that it is connected in the conventional manner (H-H-V-V).

 

Do you have 2 possible connection points as shown below?

Si-727.png

If not, then ignore everything that I'm saying and I've wasted my time.

 

The reason why there are the 2 connectors is because you can mirror the image if so desired by swapping to the other connector. So the horizontal wires would swap positions with each other from one connector to the other and same with vertical.

 

Repair guide that may help.

http://www.arcade-museum.com/manuals-monitors/Sharp%20Image%20SI727RDS%20Monitor%20Repair%20Guide.pdf

 

Image showing underside of chassis (Above connectors highlighted). Notice the pins shorted from one connector to the next.

IMG_0736.jpg

So as you can see the horizontal pins swap positions as do the vertical. If it was a H-V-V-H connection, then pins 1 and 4 would be shorted and the same with pins 2 and 3.

 

Hope my reasoning makes sense, it's late, I'm tired but this was bugging me.

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Thanks for the input mate- I'm totally new to it as well so learning a lot!

 

I will have to re-read most of these suggestions a few times for it all to sink in but this thread seems to mirror what you're saying (

https://www.aussiearcade.com/showthread.php/72764-Which-wires-for-V-and-H-yoke-connections

 

If getting them wrong doesn't do anything harmful I'll happily swap swap away but some posts on other forums mention things getting fried.

 

The chassis does have the two rows as in your photo Mosfet.

 

Thanks for the input.

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Do you have 2 possible connection points as shown below?

[ATTACH=CONFIG]118402[/ATTACH]

 

That is so you can rotate the image 180deg

Some chassis don't have that and that is why you see the plug cut in half so each half of the plug can be rotated.

Rare to see the plug cut into four separate connectors.

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Well I've plugged it in and turned it on and nothing has blown up. The image is upside down and possibly mirrored, but that's not a concern as I'll just swap V wire position to V wire position and see what happens. Do I need to discharge the tube at the anode to make these small changes at the chassis board?

 

There's also some static and horizontal lines across the middle of the screen, what pot should I adjust to start addressing those?

 

I will post some photos when I have it the correct way around to make it a little easier

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Well I've plugged it in and turned it on and nothing has blown up. The image is upside down and possibly mirrored, but that's not a concern as I'll just swap V wire position to V wire position and see what happens. Do I need to discharge the tube at the anode to make these small changes at the chassis board?

 

There's also some static and horizontal lines across the middle of the screen, what pot should I adjust to start addressing those?

 

I will post some photos when I have it the correct way around to make it a little easier

 

No, you don't need to discharge the tube.

 

The horizontal lines might be re-trace lines you're describing, turn down the screen voltage and see.

 

Regards,

 

Johns-Arcade.

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Thanks Johns-Arcade.

 

I'm not sure which pot that is.

 

I have R-Bias, G-Bias, B-Bias, R-Drv, B-Drv, Sub Bright on the neck board;

 

The usual 'focus' and 'screen' on the flyback;

 

And V-Hold, H- Hold, H-Posi, V-Posi, Pin Cush, Contrast, H-Width, L-Line, V-Size and Brightness on the remote adjustment board.

20171025_200728.jpg

20171025_200707.jpg

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Whoa, that image needs a huge amount of adjustment :)

 

The screen voltage pot is the one labelled screen on the flyback. Adjust it down and you will see your brightness go down. It will get rid of the retrace lines. You need to bring up the test screen to get colour bars and test grid pattern to do proper adjusting.

 

However, there is a whole shitload going on here, far more than just retrace lines. It looks like you may need to adjust the horizontal hold to stop the image tearing, but I've never seen anything quite like what your image is doing. Why is the image tearing in game, but not in the character select? Or had you done some adjustment between those two photos?

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Can graphical errors like that be in-game things? (In the PCB) Or due to loose fitting edge connectors?

 

I may have adjusted in between shots.

 

I have other JAMMA pcb's I can put in

 

- - - Updated - - -

 

One more thing I forgot to ask on that Namastepat, is the test mode the 'test' dip switch on the game or the test switch on the power distribution box in the cabinet?

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If the test button on the distro box is correctly hooked up to the JAMMA harness, pushing that will put the board into test mode. If it's not correctly hooked up, just look up the dip switch settings for the board online and then flick the appropriate dip to put it into test mode.
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One thing that may help (I'm still on the same JAMMA PCB) on the character select screen, moving the select box to the right or left or up and down changes the frequency of the static disturbance. It seems to be the same as what was occurring on the previous chassis. So perhaps it's in-game stuff?
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I've played with the screen voltage adjustment (turning in ver small increments) and the H Hold and can't get rid of the horizontal white lines or the erratic tearing which comes and goes every few seconds through different levels of the screen.

 

I might double check all connections are tight, try again and if no good perhaps swap to the other 26" tube which has been run perfectly by a playstation 2.

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