Blast city monitor issue

[fruktprins]

Hi,

I recently purchased a Sega Blast City with a Pandoras Box 4s. Before transportation everything was working fine but when I power it on at home the monitor is all blue with horizontal lines and it dies after a few seconds. Game seems to be working fine. Controllers and sound works even though I cant see anything. Unfortunately I dont have any other pcb to test currently.

It looks like this:

The monitor is a Nanao 2930s with dipswitches that are correctly set to down, up, down for 15k. I have checked every connection I can find and they all seems to be connected properly. This is my first cab and I don't know where to start the troubleshooting.

Thank you!

[atro]

I had a similar issue as you're having.

Turns out the neckboard was faulty and some components had to be replaced.
Doesn't mean it's your issue, but it can be related to that. Send it to a professional.

[RMRM]

He has a raster signal, so it tells me that the chassis/tube has some kind of "life".

i don't know nothing about those Pandora's box, but does that particular model output other frequncies? You might want to check the Pandora's box manual and make sure it is set to output 15Khz.

Besides, there are post on the forums from people with the same chassis that lost 15khz sync and only got 31khz and vice versa, so it would also be smart to try a different sync signal.

[fruktprins]

Thank you! This particular model of pandoras box cannot output different frequencies. I will get another board to test with and also test something in the vga port as a first step!

[grantspain]

looks like blue gun full on- could be neck card not home

[fruktprins]

looks like blue gun full on- could be neck card not home

Hi grantspain! Could you be a little more specific? Are you saying that the neck card could be a bit loose? So just push it in?

[grantspain]

yes exactly but be gentle