Hantarex Polo Problem

[RedPainter]

Hi to all,

I'm restoring na old arcade cabinet (from 1993), it has an Hantarex Monitor with a Hantarex Polo 25" chassis.
Games are running from a SNK MV-1B system.

The monitor had some problems when I bought it, I've cleaned it up and replaced ALL electrolytic capacitors, which made the image much better but not completely fixed.
The image seems to be jumping in the vertical direction, the problem can be seen in:

(Overall image)
(Top of Screen CloseUp)
(Bottom of screen CloseUp)

The video was shot with the camera sitting on a tripod, so the shacking is from the monitor image and not from the camera.

I've been looking for capacitors shorts, malfunction in transistors and IC , opened resistors but for the time being i'm not successful in fixing this problem.

I've got little knowledge of electronics and fair skills on soldering.

Can any of you guys help me out over here?

I feel that I've already spent much more time with this than what I should, I'm starting to plan to give this to a repairman cause my wife is starting to be mad at me to have all the parts laying around in the house.

The kid asking: When will we be avaible to play?
The brand new buttons and J-Pac laying around screaming to be used...

In sum I'm frustrated, and this is the first of two Hantarex Monitors to repair, I hope the second won't struggle so much...

Hope to hear from you soon.

Best regards,

Andre Andrade

[grantspain]

you should meter the 25 volts to the vertical deflection ic
you also have some serious pincushion

[RedPainter]

Hi grantspain!
Thanks for your reply.

The pincushion is easily fixed with the control pots.

What I can't fix is the jumping of the image.
Which is the vertical deflection IC?
TDA 1675 (IC 103) or TDA 2593 (IC 104)?

Which IC pin should have the 25 volts? Pin 2 on TDA 1675?

[lilshawn]

Which is the vertical deflection IC?
TDA 1675 (IC 103) or TDA 2593 (IC 104)?

1675 is the deflection chip, 2593 is the sync seperator.

Which IC pin should have the 25 volts? Pin 2 on TDA 1675?

pin 14.

replace any caps tied to pin 14 as well.

[RedPainter]

There is 27.1 volts betweenTDA 1675 pins 14 and 8 (ground).

Should this be 25 volts precisely? Or is this near enough?

All the electrolytic capacitors were already replaced.

I don't see any cap tied to pin 14, at least directly...
Which ones are refering to? C137, C138 and C139?
C137, C139 are fresh new, since they are electrolytic.
C138 I don't have a new to replace, but i've checked if it was shorted, and it wasn't.

I can upload the schematics if you don't have it.
I have the diagram that came with the cabinet.

[grantspain]

on r167 you should have 26.1 volts or near,i thought the VCC on the tda was pin 2
there are a couple of small caps that also cause this type of issue-need to grab a chassis tomorrow to tell you which ones
that could also be something to do with the primary psu of the chassis-there is a current inrush component that i have seen cause similar issues also make sure the screw that bolts throught the chassis earth is present

[lilshawn]

i thought the VCC on the tda was pin 2

the datasheet doesn't really specify which is which, it shows several "supply" pins... the block diagram shows pin 14 is tied to the internal voltage regulator. that would be my educated guess as the "VCC"

[dextercf]

Got the same problem, only not that much "wobbling".
Also I have an older Hantarex.

Where do you guys find the schematics and such for these monitors?

[princess prin prin]

I don't see any cap tied to pin 14, at least directly...
Which ones are refering to? C137, C138 and C139?

C138 and C139 are directly connected to pin 14.

on r167 you should have 26.1 volts or near,i thought the VCC on the tda was pin 2

It's pin 14, connected to R167. Pin 2 is the amp supply, connected to R167 through D127.