PAL 7800 Picture Quality Issues

[Chatty75]

Hi Everybody,

 

I recently found my 7800 in a cupboard and set it up again after spending the last year or so alternating betwen an Irish 2600jr and my old 2600 Woody.

 

Anyway, the thing that I first noticed was how terrible the picture quality was on the 7800, even the old 2600's are both far superior to it as there are vertical lines on the left hand side of the screen and various other artifacts all over the picture when playing any 7800 cartridges (although strangely enough 2600 cartridges seem to be much more stable picture-wise and don't suffer from the vertical line issue at all).

 

At first I believed this to be my old system that perhaps had got damaged in storage so I picked up another on on Ebay only to suffer from exactly the same problem, I am now on my 3rd model and the same thing is still happening, I thought it may be a TV tuning issue but I have now tested all three machines on three different sets around the house, ranging from a 2 month old HDTV to my old but fully operational 1981 Toshiba Cube set with manual dial tuning (the same set I have used with the 2600 Woody from childhood) and still the issue persists,

 

Is this a common issue with most PAL 7800's of a certain age or is there anything you can advise that may clear up the problem? It's just that i don't seem to remember this happening when it was new and as it doesn't happen to either of the 2600's i've kind of ruled out the TV's themselves.

 

I don't really want to have to go to the expense of having it modified unless I have to, partially because of cost and also because the original 12" colour Cube TV (RF only) fits nicely on my desk for me to have a blast on while i'm also working on the PC and still gives me that proper retro feeling you don't get though a massive modern LCD.

 

Any advice you can can give me would be much appreciated.

[Mayhem]

My PAL 7800 isn't that great through RF either. It's partly why I prefer to use my S-video modded NTSC console instead.

[Rybags]

2600 mode video originates from TIA. 7800 mode you're probably getting extra noise from Maria DMA.

 

Agreed, the RF out somewhat sucks. The other factor is that the RF jacks themselves are poor quality metal and easily oxidise which degrades the signal quality further. Some contact cleaner on cotton bud might help a bit there.

 

Rather than buying another and hoping, an S-Video mod is a much better way to go. But the ones out there aren't necessarily compatible, there's multiple revisions of the motherboard and the layout changes a fair bit among some.

[16BitMan]

Mine is bad too but I found if I used it through an RF signal booster its loads better!

[mimo]

There is a pretty simple AV mod on circuit-board.de that works ok on one of my pal consoles. The best display. Is from my French 7800 that has rgb scart. Looks great on crt but awful. On LCD and plasma

[Rastignac]

I have two french 7800 now, with RGB scart output.

One seems fine, but has some kind of strange red lines dirtying the picture. It runs fine on all TV sets (CRT or LCD).

The other one displays colors only for the 2 leftmost centimeters of the picture, then all grey for the rest of the image. I should try to open it and look for a bad part to fix.

I talked with other french 7800 owners, and they all have little or big problems with their 7800s.

An as-old-as 2600jr with RF output is always better on screen than a 7800 with RGB output; damn.