Amplifone Color X Y Vector PCB question.

disjaukifa

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Hey Guys,

I've got a Amplifone that is almost perfect except the image is waving/rippling, and if it weren't for that it would be perfect. Any ideas?

Thanks
Grant
 
Here is a video of the issue:



Thanks
Grant

During assembly of the Amp prototype I had waves like this (Well, mine was worse)

It ended up being the values of R14 and R72 were wrong
See this diagram, it's the circled resistors
http://www.dsbelec.iinet.net.au/Amp_Defl&HV_Schematic_Dez_FINAL.jpg

I fitted 12K and 16K originally, when they should be 1.2K and 1.6K

The schematic I initially got from the net was wrong.


During the process of finding this problem I looked far and wide, and found other things that COULD cause this: I found . . (On Defl. board)
Deflection Transistors (Them large bottletop ones) - could be counterfeit etc
Large Resistors R6 and R29 (If they were inductive, supposed to be NON inductive)

All the best
 
During assembly of the Amp prototype I had waves like this (Well, mine was worse)

It ended up being the values of R14 and R72 were wrong
See this diagram, it's the circled resistors
http://www.dsbelec.iinet.net.au/Amp_Defl&HV_Schematic_Dez_FINAL.jpg

I fitted 12K and 16K originally, when they should be 1.2K and 1.6K

The schematic I initially got from the net was wrong.


During the process of finding this problem I looked far and wide, and found other things that COULD cause this: I found . . (On Defl. board)
Deflection Transistors (Them large bottletop ones) - could be counterfeit etc
Large Resistors R6 and R29 (If they were inductive, supposed to be NON inductive)

All the best

Ok Now I'm a little frustrated with my Star Wars, I rebuilt a different Amplifone PCB and I'm getting the exact same results, and whats really frustrating to me is that the machine never use to do this till the other day when I was messing around with my first deflection board to try to figure why the red color gun was sometimes disappearing.
 
Ok Now I'm a little frustrated with my Star Wars, I rebuilt a different Amplifone PCB and I'm getting the exact same results, and whats really frustrating to me is that the machine never use to do this till the other day when I was messing around with my first deflection board to try to figure why the red color gun was sometimes disappearing.

I have the exact same thing with my Star Wars. I've tried two different deflection boards as well and the problem remains. I haven't tried really hard to narrow the problem down, but I'm pretty sure it is not the defection board. If I get some time this weekend, maybe I'll do some more troubleshooting.
 
I had a few minutes to look at mine today. Just for kicks, I replaced big blue to take it out of the equation. No change. Unplugged marquee light and fans (I added an extra on my HV board). No change. DC voltages good, no excessive AC ripple, fuse holder is new, all grounds connected. ??

Not sure what it could be.
 
I had that same wavey screen problem with my 6100 on my Black Widow. Turned out it was a loose wire going to one of the bottlecap chassis transistors. I replaced the transistor and flowed new solder on all the wires to it and the screen stabalized. I know yours is an Amp deflection board but they use the same bottlecap transistors. For what it's worth.
 
I had a few minutes to look at mine today. Just for kicks, I replaced big blue to take it out of the equation. No change. Unplugged marquee light and fans (I added an extra on my HV board). No change. DC voltages good, no excessive AC ripple, fuse holder is new, all grounds connected. ??

Not sure what it could be.

I hooked a 6100 that does have some issues but the game didn't ripple.

Looks like a flakey ground or a ripple in the Hv. Try connecting a 6100 to it see if prob still exists.


I had that same wavey screen problem with my 6100 on my Black Widow. Turned out it was a loose wire going to one of the bottlecap chassis transistors. I replaced the transistor and flowed new solder on all the wires to it and the screen stabalized. I know yours is an Amp deflection board but they use the same bottlecap transistors. For what it's worth.

I'm about to take the PCB out and start checking all the resistors and see if I damaged one of them, I actually have an idea as to what resistor I damaged, and I did it on both deflection boards. The down side is I don't have any resistors in stock at the moment!
 
I'm still not convinced its the deflection board (at least on mine). I took one of mine down to Grinkers arcade and put it in the Star Wars there while I was fixing their deflection board and there where no ripple issues?? I don't know now.
 
Last edited:
Can you get a scope? If so, have a look at the ripple on the +24 and -24VDC coming in, needs to be pretty smooth

There are 2 x Medium caps on the HV (C3 and C4) which may be sus

Also, are R20 and 21 fitted on your HV Board? (Across the 2 regulators)
http://www.dsbelec.iinet.net.au/Amplifone_HV_Schematic-A201012-04_WITH_PLUGS.jpg

Not to sound like a moron, but I do have an oscilloscope that I know works, but I have never used it, how do I do what you are talking about above?

Also I think I need to change the resistor on my HV pcb because I have the focus knob turned all the way and its still not quite in focus yet.

Thanks
Grant
 
Not to sound like a moron, but I do have an oscilloscope that I know works, but I have never used it, how do I do what you are talking about above?

I am at work, so I will explain this tonight :)

Also I think I need to change the resistor on my HV pcb because I have the focus knob turned all the way and its still not quite in focus yet.

Thanks
Grant

The resistor I refer to (R19) will not help you get more focus.
 
Not to sound like a moron, but I do have an oscilloscope that I know works, but I have never used it, how do I do what you are talking about above?

Also I think I need to change the resistor on my HV pcb because I have the focus knob turned all the way and its still not quite in focus yet.

Thanks
Grant

To get you used to using a scope here's a neat trick

If you have a dual trace o/scope, one probe is for X (Horiz) and the other probe is for Y (Vert)

Zero the scope (Set the horiz beam across the screen in the centre)

Clip the 2 x Aligator clips on GND on the PCB

Clip one hook on the X out on the PCB
Clip the other onto Y out on the PCB

Adjust the X & Y range and X & Y positions dials so you can see the gameplay on the scopes screen

You may have to select things like internal sync / ext sync or AC/DC etc, also intensity etc

Easy to work them out once you have a line on the screen, just keep that line in the visible area by adjusting.

Once you've had a play, let us know if you need help on how to find ripple on DC signals etc

Have fun !
 
To get you used to using a scope here's a neat trick

If you have a dual trace o/scope, one probe is for X (Horiz) and the other probe is for Y (Vert)

Zero the scope (Set the horiz beam across the screen in the centre)

Clip the 2 x Aligator clips on GND on the PCB

Clip one hook on the X out on the PCB
Clip the other onto Y out on the PCB

Adjust the X & Y range and X & Y positions dials so you can see the gameplay on the scopes screen

You may have to select things like internal sync / ext sync or AC/DC etc, also intensity etc

Easy to work them out once you have a line on the screen, just keep that line in the visible area by adjusting.

Once you've had a play, let us know if you need help on how to find ripple on DC signals etc

Have fun !

I'll work on that tonight. Also I thought I could get more focus because I have a 6100 focus block on my HV PCB and a tube swap was done on the cabinet.

Hopefully I'll get this working tonight!

Thanks
Grant
 
To get you used to using a scope here's a neat trick

If you have a dual trace o/scope, one probe is for X (Horiz) and the other probe is for Y (Vert)

Zero the scope (Set the horiz beam across the screen in the centre)

Clip the 2 x Aligator clips on GND on the PCB

Clip one hook on the X out on the PCB
Clip the other onto Y out on the PCB

Adjust the X & Y range and X & Y positions dials so you can see the gameplay on the scopes screen

You may have to select things like internal sync / ext sync or AC/DC etc, also intensity etc

Easy to work them out once you have a line on the screen, just keep that line in the visible area by adjusting.

Once you've had a play, let us know if you need help on how to find ripple on DC signals etc

Have fun !

Ok good news, the board set is fine. I connected it to my oscilloscope and Stars came on and was solid!

Now to continue on my journey of getting this machine working. Also ran into a new issue where the left thumb trigger doesn't work anymore so now I can't play Empire Strikes Back.

A tube swap was done on this Star Wars, however the original focus block was used. I'm thinking about changing it over the to the 6100 focus block so I can get more focus out of it. I will post pictures of the HV PCB and the Deflection PCB soon!

Thanks
Grant
 
Ok Here are some pictures of the HV PCB:

IMG_0336.JPG


IMG_0334.JPG


IMG_0335.JPG


Here are pictures of the Deflection board I rebuilt:

IMG_0337.JPG


IMG_0338.JPG


IMG_0339.JPG


And here are pictures of Star Wars on my Oscilloscope

IMG_0342.JPG


Thanks
Grant
 
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