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Main => Monitor/Video Forum => Topic started by: KaYs3r on January 14, 2022, 10:05:20 am

Title: Hantarex Polo diagonal lines
Post by: KaYs3r on January 14, 2022, 10:05:20 am: Hi everyone,

I have bought an "old" arcade machine, and it comes with an Hantarex Polo. I've installed a Pandora Box DX, and it works :laugh:

I'm new at this, so, the questions:

1. How do I measure the screen to know it's size? Diagonal, measuring all the glass on the screen I have 28". Is this correct?

2. As you can see on the video, when I adjust the vertical amp pot, the top horizontal lines move on top of the other lines, look at the white dots on the video. What could be the problem?

Video -> https://photos.app.goo.gl/q9zD8FGAegFUE2cd7

I've made a partial cap kit. I've found a cap kit list, but some of the caps where completly different from the ones installed on the chassis, so I looked for the schematics, and the values on the schematics where different from the cap kit, and from the ones on the chassis ???
My chassis is the one that ony has one big cap on the power supply.

I've found that diode D106 is bad, will change it. Should I look for anything else?

Thank you, and sorry for my english.
Title: Re: Hantarex Polo diagonal lines
Post by: KaYs3r on January 14, 2022, 07:30:57 pm: Hi everyone,

I've finished the cap kit, but no change on image.
Here's another picture, on Pac-Man.

Thanks
Title: Re: Hantarex Polo diagonal lines
Post by: KaYs3r on January 17, 2022, 04:45:16 am: Hello again,

After removing the diode, I've checked that it was not bad after all, but I've installed a new one, just in case.
The problem continues.
I've disconnected the Pandora Box, and turned the chassis on, and the lines are there, as you may see on the photo.

What else should I test?

Thanks
Title: Re: Hantarex Polo diagonal lines
Post by: buttersoft on January 17, 2022, 05:31:55 pm: sorry, i did watch the video but it didn't twig what i was actually seeing. It looks like vertical foldover of some description. Giving that termr a google would be a good idea. Normally fixed by swapping out the vertical pump-up capacitor, on consumer CRT's at least. Not certain about arcade chassis.
Title: Re: Hantarex Polo diagonal lines
Post by: KaYs3r on January 18, 2022, 02:36:00 am: Thanks for tip buttersoft,
I'll try to find the pump-up capacitor, it has to be one of the film capacitors because I've changed all of the electrolic.
Do you think I should swap the vertical IC too?

Thanks 👍
Title: Re: Hantarex Polo diagonal lines
Post by: buttersoft on January 19, 2022, 05:39:02 am: The pump-up cap will be an electrolytic. Hmm, in which case, did you test the caps before putting in? If it's not that, it might be related to the IC i guess.

If you can identify the vertical IC and get a part number, the datasheet for it should show a typical circuit, including the pump-up cap. You might be able to identify it that way, especially if you have the schematic for your chassis. Or the circuit might show something else that's relevant.

This is me speaking from limited experience though, i'd love it if someone who knows something about Hantarex Polos would chime in :/
Title: Re: Hantarex Polo diagonal lines
Post by: KaYs3r on January 19, 2022, 11:40:27 am: I have already changed all the electrolytic caps for equivalent new ones. I already have a new vertical IC, I think I'll try to install it...

Thanks
Title: Re: Hantarex Polo diagonal lines
Post by: KaYs3r on January 19, 2022, 05:23:58 pm: So, I've changed the vertical IC, and problem persists.
There is another problem, that already happened before switching the vert IC, the shape of the image is changed depending if there is bright or dark colors on the screen.

Anything else I should try?

Thanks
Title: Re: Hantarex Polo diagonal lines
Post by: buttersoft on January 19, 2022, 05:53:22 pm: How is the shape changing? Bloom, or an the image expanding on bright screens, is normal. A lot of the time it happens depending on whether a scanline or section of lines is brighter - so the brighter (top/bottom/middle) section of the screen will expand, especially horizontally, but the darker sections won't.

I have to admit this is where my remote diagnosis ends, sorry. I don't know how to continue unless you can provide a schematic, and possibly the part number for the vertical IC. Even then i might not see anything. There are people on here with much more experience than me, so hopefully one of them has knowledge of your monitor, and decides to stop by in the next couple of weeks.
Title: Re: Hantarex Polo diagonal lines
Post by: KaYs3r on January 20, 2022, 09:43:50 am: Quote from: buttersoft on January 19, 2022, 05:53:22 pm
How is the shape changing? Bloom, or an the image expanding on bright screens, is normal. A lot of the time it happens depending on whether a scanline or section of lines is brighter - so the brighter (top/bottom/middle) section of the screen will expand, especially horizontally, but the darker sections won't.
Yeah, that's it.

Quote from: buttersoft on January 19, 2022, 05:53:22 pm
I have to admit this is where my remote diagnosis ends, sorry. I don't know how to continue unless you can provide a schematic, and possibly the part number for the vertical IC. Even then i might not see anything. There are people on here with much more experience than me, so hopefully one of them has knowledge of your monitor, and decides to stop by in the next couple of weeks.

Here you go, I've attached the schematic, I don't know if it is exactly the same model, I see some different models of this chassis.
The vertical IC is the TDA1675a or TDA1670a (they are equivalent).

Thank you for your help