No picture after buzz off install

[BringerOdeath]

Hello guys,

 

I was doing a buzz off install for a customer and after the install, I get sounds, but no image. I checked the voltages from j204 and they look fine, didn't really touch anything on the crt side or power board. So I am kind of perplexed. If i turn the lights off, there is a faint glow of the filament. I do a ton of mods, but this is the first time I have worked on a vectrex. Any ideas would be great!

[+Mitch]

Did you accidentally turn the brightness all of the way down?

 

Mitch

[BringerOdeath]

I turned the knob both ways and there is no image on screen at all. Just sound. It was working perfectly until I installed the buzz off. This is a rare vectrex that has the soldered sound ship instead of being socketed so I had to cut a trace and run the 3 wires to the sound chip. I turned the knob both ways and there is no image on screen at all. Just sound. It was working perfectly until I installed the buzz off. 

[BringerOdeath]

Figured the issue out. The j204 wasn't making good connection to the cpu motherboard. Cleaned the connections with deoxit and it sprung back to life and without any buzzing! Woohoo!

[CatPix]

I was about to say that. Also you may have noticed that the Vectrex PCB is dual side, but there is no vias; all connections through boards are made by component legs being soldered on both sides. It cause a plethora of connection issues due to dry solder on both side over time!

[+-^CrossBow^-]

On 1/20/2020 at 8:22 AM, CatPix said:

Also you may have noticed that the Vectrex PCB is dual side, but there is no vias; all connections through boards are made by component legs being soldered on both sides. It cause a plethora of connection issues due to dry solder on both side over time!

I've stated more than one on a Vectrex fan FB page the importance of soldering to both bottom and top when doing the caps..etc because of this and keep getting told I'm crazy so..ehh..whatever. It came up because someone was called out for having their caps mounted high water off the board. I advised this wasn't a bad idea in the case of the vectrex since there are traces on top and bottom for many of the components and you need to solder to both sides to make sure you make good connection.

[Level42]

On 2/3/2020 at 2:21 AM, -^CrossBow^- said:

I've stated more than one on a Vectrex fan FB page the importance of soldering to both bottom and top when doing the caps..etc because of this and keep getting told I'm crazy so..ehh..whatever. It came up because someone was called out for having their caps mounted high water off the board. I advised this wasn't a bad idea in the case of the vectrex since there are traces on top and bottom for many of the components and you need to solder to both sides to make sure you make good connection.

As I have learned by re-capping a Vectrex the past few days: you are absolutely correct. I even had one track coming off....fixed it with a piece of capacitor "wire"....

The worst thing is that the cap-kit didn't solve my problem....

[nick3092]

On 1/20/2020 at 8:22 AM, CatPix said:

I was about to say that. Also you may have noticed that the Vectrex PCB is dual side, but there is no vias; all connections through boards are made by component legs being soldered on both sides. It cause a plethora of connection issues due to dry solder on both side over time!

Having recently replaced some caps on mine, I can tell you that is not always true. With caps removed (solder all sucked out with my hakko gun), I used my DMM to confirm continuity between bottom and top solder pads. It was there.

 

Not to say they can't get damaged while doing rework, or maybe some board revisions didn't have the vias. But it's certainly not a blanket statement that they don't exist.