Lines through picture

[benducklow]

Hi there. I know you folks know your systems (better than I) so I thought I'd see if any of you have a solution for my recently revived Atari 2600. My picture quality is kind bad; I get wavey lines though the picture. I can still see everything but its kind of distracting. I am not sure if the its the game adapter, the cart (I think all my carts produce some sort of lines) or the fact that I am using the game system on a newer (CRT) TV.

 

Anybody help a born again Atari fan?

[Dauber]

Sounds like just a poor connection between the unit and the TV.

 

Now...first of all, which 2600 is it? If it's the woodgrain or "Vader" model, it could be the cable...I got a heavy-sixer once on which the original owner replaced the coax cable...but the thing is, the end of the cable was too long to completely cover the jack inside the case. I found an old cable with a shorter end and replaced it -- that worked.

 

With my 2600jr, Intellivision, and 7800, I just plug in one of those heavy-duty gold-plated insulated RCA cables -- man, I've never seen a better picture! It's a good thing that the three units I have actually have coax ports rather than in-built cables...

[Brian R.]

Hooking it up to a new TV shouldn't cause any problems. I use my Atari systems on a 32 inch Toshiba.

 

Definitely check the cable. And if possible, replace it with a higher quality, well shielded one.

 

Also, if you're using a TV/Game switchbox, don't. It's not really needed. Best solution is an RCA to coax adaptor that you can find at Radio Shack.

 

It's also best to connect directly to the TV. I know my picture quality degrades when I, for instance, run things through my VCR.

[keilbaca]

If you want the clearest picture, get it audio/video modded.

 

Next up is using the RCA-COAX adapter in the Atariage store.

 

As stated as well, check the cable, and don't be afraid to change it.

[benducklow]

Thanks everyone. I knew you guys would know what to do.

 

Dauber: you were talking about COAX...did you mean RCA? The only COAX I have is from the game adapter to the TV...

 

If you meant RCA, if I take apart my woodgrain 2600, is there a simply RCA style jack in there that I can disconnect so I can replace the cable? Or is it soldered on the main board? I know the cable than runs out from my 2600 to the game adpater is pretty thin and is very long.

 

KEILBACA: I actually looked into getting it modded with s video and component audio/video out from oldschoolgamers.ca but looks like its $90 plus shipping...ouch.

 

I'll definetly be looking into the RCA-to-COAX adapter.

[godzillajoe]

I went to radio shack and bought a ten db signal booster and instead of using that stupid TV/Game slider switch box, bought a female RCA to male F Type apadter for $3 and it was 10000% better picture.

 

See this thread

 

http://www.atariage.com/forums/index.php?s...er+interference

[Dauber]

Thanks everyone. I knew you guys would know what to do.

 

Dauber: you were talking about COAX...did you mean RCA? The only COAX I have is from the game adapter to the TV...

 

If you meant RCA, if I take apart my woodgrain 2600, is there a simply RCA style jack in there that I can disconnect so I can replace the cable? Or is it soldered on the main board? I know the cable than runs out from my 2600 to the game adpater is pretty thin and is very long.

 

Yeah, I meant RCA, actually....

 

If you open up the casing on your woodgrain, you'll see that the RCA cable connects to a simple, standard RCA port on the motherboard. Make sure it's attached fully and that the little tabs around it completely cover the port....

[supercat]

Dauber: you were talking about COAX...did you mean RCA? The only COAX I have is from the game adapter to the TV...

 

The term "coax" refers to a coaxial cable in which one conductor is completely inside the other (the latter being basically a braided tube). Coaxial cables used for carrying RF video signals usually have a characteristic impedance of 75 ohms. This is a nerdly detail, but it's important: whenever a signal passes between two points that have a different characteristic impedance, some of that signal will be reflected. The 2600 is constructed so its output jack has a 75 ohm impedance; any decent television set should have an input impedance of 75 ohms. Using a cable with a characteristic impedance of something other than 75 ohms will often cause ghosting since the signal will reflect when it reaches the TV set of the cable and reflect again when it hits the 2600.

 

BTW, the screw-terminal twin-lead cables and connectors had a 300 ohm impedance. If you look inside a typical switchbox you'll find a small transformer which has a 75 ohm impedance on one side and 300 ohms on the other.

 

One point of confusion is that there is a common type of connector, an "F-connector" associated with coax cables and only coax cables. This is sometimes called a "coax" connector. Typically, the central "pin" in the isn't actually a pin at all--it's the central conductor of the cable (hence the fact that such connectors only work with such cables). Many common RCA to RCA cables these days, even ones designed for audio, are also of coaxial construction, though ones not designed for video may have a characteristic impedance other than 75 ohms.

[benducklow]

I was able to try one thing; I tried swapping the RCA cable that leads off the motherboard to the game switch and found out it was worse! This RCA cable is of good quality so I am not sure if this is relating to what SUPERCAT was speaking of... In my process of putting back the old RCA cable, I bent in the outer connectors on it so it would clasp the connector on the board a bit better and it did improve the picture. Not perfect, but alot better.

 

I'm going to try and scor one of those RCA-to-F connectors from a local Radio Shack this afternoon and give it a whirl tonight.

 

I think its time for me to start re-plenishing my cart collection with some of the classics!

[benducklow]

Problem solved baby! Went to Radio Shack and got an RCA-F connector adapter and she looks SWEET. Crisp, clear picture. I'm loving it! Time to head back to the tube and play some Space Invaders!

 

Thanks everyone!