Jouster

Here is a picture just taken using VBXE and an LCD TV

Thanks for the reply Rybags I tried shielding the cables with foil and also shielding the Antic chip, but no difference at all. I am starting to think the noise is being fed to the cables at source and therefore no amount of shielding will help. The only place I can think of is via Csync. Could the noise be originating from there? If not, are there any other connections that could be picking up this noise? Here is a picture of my current connections.

@flashjazzcat - Nice Youtube channel. Watched you fit a socket where the RF used to be, but I'm affraid my skills don't stretch that far.... Anyway, doesn't seem to make a jot of difference where the cables are, there is always that bit of interference on screen. Not on all programs/games, some look perfect. Put the machine back together as I'm going to just live with it for a while. I may try another solution in the distant future. One last thought, could it be the PSU??

I tried it also with the modulator removed, but no difference. I only put it back to maintain the composite signal. I move the wires around and no change. I will remove the RF again and try the ribbon cable idea and see if that makes a difference. Things you think are going to be straight forward, very rarely are with these old computers! Thanks for your help

browny/red wire = sound (top of resistor) grey wire = common ground (black goes to VBXE gnd) orange wire = composite signal white wire = blanking browny/orange wire = VBXE green red wire = VBXE red yellow wire = VBXE blue the grey wire is connected to all relevant ground points on SCART

Moved the cable around in the computer, but it didn't make any difference Only 3 cables are connected to the motherboard on the SCART: All ground to common ground mentioned earlier Composite (PIN 20) to Composite signal on Monitor Jack Sound (PIN 2 & 6) to Sound signal on Monitor Jack All others go to the VBXE, so it can't be them. I think the interference (noise) must be in the Composite signal. As mentioned earlier, changing this to PIN 15 of CD4050 did not resolve the problem. Any ideas?

apologies, I miss-read. Move it around, not remove ground! I need more sleep!

Thanks for the reply! Yes, I'll open up and remove the common ground I attached to the mobo. Will this be safe without any ground on the SCART? Or do I need an alternative ground? Here is what I have at the moment: VBXE - J4 PIN1 (gnd) connected to ground near modulator All ground of SCART connected to the same point

I have attached a photo of the picture using the standard Monitor port to my CRT TV, as the lines are too faint via the VBXE. Via the VBXE the lines on the left are faint but still clearly visible, particularly on blue (Sky, Water etc). I connected Composite out to PIN20 of SCART as advised in the installation guide. After seeing these lines I tried connecting to pin 15 of CD4050 (Csync) instead, but it was exactly the same. The CRT TV is connected via SCART, and the connections are as per the guide. Don't get me wrong, the picture is still very good indeed, but I didn't expect to see 'any' lines in the picture from the VBXE

I was pretty sick of the crappy picture on my Atari 65XE, the vertical were really bad, as was the noise interference. So I decided to bite the bullet and get a VBXE from Lotharek. Anyway, I received it the other day and installed it last night. I must say that the picture is much improved, and I have an extra 256kb of memory to boot However, I noticed slight lines still in the boot screen and it's worse in certain games (i.e. Pitfall II has vertical lines on the left side of the screen). One of the reasons I bought the VBXE was that I knew it was a graphics card and assumed it would eliminate all these vertical line issues. Can you guys share your experience with this expansion, did it cure your display problems?

I did the mod on my Flashback 2 but with a top mount. Never thought to put it in the side, what a great idea! Was a bit disappointed with the Flashbacks compatibility though, so still use my Jr...

I have a 65XE that won't work, someone suggested it may be the MMU chip thats at fault as I have already changed all RAM, CPU, Pokey and ROM. I think I read somewhere that you can program a GAL 16V8 chip as a replacement, maybe worth looking into if you have a programmer

I guess I'll just keep replacing random IC's until it starts working. I was hoping to avoid having to do this but it seems unavoidable. I'll leave the MMU till last since it's the most difficult to come by over here. I'll post how I get on for anyone interested. Thanks very much for the help anyway guys

Thanks for this! 1) The only socketed chip is Freddie (C061991), I'm socketing more as I try changing chips; I've swapped all RAM for NOS 4164B-12 Swapped CPU System ROM Pokey All seated ok 2) No luck with this, still boots with random screen colours, sometimes lines down screen 3) PSU giving 5.02v under load 4) Yes, I'm using RF. Crappy picture but I can see what the computer is outputting. And it's not the normal boot screen... No Prompt, just the aforementioned randomly coloured screens 5) I don't own any carts unfortunately. The only two IC's that get 'Hot' are the CPU and System ROM C014806 & C061598B As in my previous post, should Freddie be stone cold?

Hi electrotrains, doesn't look like the MMU chips are readily available in the UK Where did you get yours? How much with shipping? Is there a way of testing the one I have to see if it is working? As I say I do have a logic probe.. Update: Computer been on for 30 minutes, should freddie be stone cold??

No problem, I should have explained it better After 10 minutes or so, the only two 'hot' chips are the CPU and system ROM C014806 & C0615988 All other chips are cold to warm. The screen is coming up brown mostly now, sometimes light blue...

Let me clarify, I'm in PAL land, so my previous A800 was a PAL system. The green screen is a solid green screen (no prompt). It sometimes comes up brown, sometimes totally black. Sometimes it has lines down the screen also. i.e. the system is not getting to the basic prompt at all I thought it was the system ROM, but changing that didn't help. I haven't tried changing the Basic ROM as yet. I have a logic probe but not really experienced in using it. So have changed the most of the 'common' problem chips in the hope that I got lucky. The power supply is giving 5.02v under load. What do you suggest I try next guys?

Hello all, I am a frequent visitor to this forum as I have several Atari systems (7800, 2600 etc). I've joined in the hope that someone can help me with a problem... I decided to get an 8bit system, as I used to own one (Atari 800) back in the day. My PAL 65XE arrived last week and I eagerly powered it up to a green screen I could not complain to the seller as system was sold as untested. Right here is what I have tried so far: Changed all RAM - X8 Changed CPU - C014806-12 Changed ROM - C061598B I even swapped the Pokey to see if that was the problem, but still no joy. I suspect you guys have vast experience in getting these old systems working again, so I'm looking for some advice/guidance. I'm determined to get this going! BTW, it looks like it's a 130XE motherboard inside this 65XE Thanks in advance