Harmony Cart Interference

[potatohead]

$.000... classic case of not worth it, literally!

 

[+Philsan]

Fred, I have just compared Monk's video, in particular Harmony's Pitfall part, with my Harmony's Pitfall output.

I have found that the interferences are exactly in the same position!

So at least it's now clear that it's not a problem form outside (Monk, you can keep living near an airport!)

 

I would do everything to help you fix this problem so I am glad to answer to your questions.

I have tried changing channel: the "interferences" remains and are identical, exactly in the same screen position (as you already know every game has its own amount of interferences in different positions).

Normally, if you have problems with video cable, if you bend or move it, interferences change.

Nothing changes if I move my cable (or I add the ferrite bead).

 

PAL's VCSs have a video cable attached to the console, PAL's JRs have an RCA plug.

Here is the cable used (obviously VCSs don't have the right plug):

I don't use switch boxes.

I hope you'll be able to fix my cart or make a new revision with no PAL interference (I would pay without problems).

[Monk]

ok just putting my .02 cents in thats all.

 

Two hundredth of one cent? Wow, that's very little amount (-8

 

Did you pay with Paypal?

 

.02 is two cents

 

.02 DOLLARS is two cents. .02 CENTS is two hundreth of one cent.

 

- Monk

[Monk]

I dug out my NTSC Jr. and tried some experiments. No interference unless I literally wrapped the video cable around the Harmony cart 5 times before it was noticeable. I went and wrapped it 5 more times and the game was nearly unplayable. However, even then, the interference was then reduced almost to zero by putting a ferrite bead around the cable just as it exits the 2600, even with this cable wrapped around the cart.

 

I can assure you, my cables have never been wrapped around the harmony cart.

 

I also noticed something about the Jr. I had not noticed before - it does not have its own video cable but rather just an RCA plug and you use your own cable. If you aren't using a fully sheilded coaxial RCA cable (e.g. if you are using an audio cable or other non-shielded cable) I can see how interference could be an issue. I'd recommend trying a quality, fully shielded video cable and a ferrite bead attached near where the cable plugs into the console. When I do this, there is absolutely no interference from my Jr.

 

Yes. But I bought specifically very well shielded, expensive RF cables for this particular purpose. The effect; no change in interference. Well, to be exact, slight change in the NORMAL RF INTERFERENCE, but no effect in _THIS_ particular interference.

 

It is also worth noting that I tested a Combat cart as a control and the interference was worse than Harmony for all tests, but in any case it became crystal-clear after adding the ferrite bead. The sweet spot for the ferrite bead seems to be about a 6 inches to a foot from where the RF cable exits the console.

 

The reduction of interference with the ferrite bead was so dramatic that I am thinking of posting a video.

 

Sure, but keep in mind, that you are testing with an Atari unit that didn't have any interference to begin with, and the interference you are talking about thus might not be THE SAME interference we are talking.

 

Did it look exactly the same as my and Philsan's interference, or was it just the 'regular RF interference'? How about the interference in SOUND? (as you can hear in my videos)

 

Personally, my diagnosis is, that as the interference still exists with also my NTSC Atari, some Atari units just HAVE it, some DON'T - and most of the Harmony Cart owners here seem to be just lucky that their Atari's do not have it. Would be interesting to exchange our Atari units for awhile and see what happens .. I mean, me sending you my NTSC Atari jr and you sending me yours..

 

(but it'd be too much trouble)

 

So, I guess some Atari's are faulty in this way, and there's probably nothing that can be done about it. I guess I can live with that.. if only I could get hold of even one, even a PAL Atari that wouldn't have that interference, it would be of course easier to live with..

 

Now that NTSC problem bothers me so much though that I even dreamed of NTSC televisions which showed my NTSC Atari's picture with color and sound..

 

But that's probably a problem for another thread, so I won't bother you more of that here and now.

 

Just a warning; DO NOT think you can get NTSC Atari working easily in europe, at least not in Finland!

 

- Monk

[Monk]

I am not disagreeing that interference must be coming from Harmony in your case. That doesn't mean that there isn't a solution to minimize the interference it does produce. It's not feasible to redesign the Harmony at this point. I have already paid many thousands of dollars for circuit boards and professional assembly of the boards and really can't afford to throw them all away.

 

And in my case.

 

There might be a solution to minimize the interference, sure. But so far we have both tried 'almost everything', and nothing has changed it _AT_ALL_. So perhaps it's becoming a bit interesting question - exactly WHAT would that solution be?

 

Too bad about the redesign-non-feasibility - but how about creating just a few new carts with something done about that interference, that you could then sell for people who specifically have this problem? Then everyone would be happy.

 

If you can answer some more questions, I'd appreciate that. Do PAL consoles allow the signal to output on more than one channel? If so, can you try the other channel? Also, are you using a switchbox or one of these on the end?

 

It is not a PAL console specific problem anymore, as the NTSC Atari I got, also has the interference with Harmony Cart.

 

We don't usually use switchboxes here in europe - or at least here in Finland.. we have those RF cables that Philsan showed a picture of, and then with the older Atari's like the VCS and Darth Vader model, this kind of cable is permanently attached to the console itself, so using another cable is out of the question anyway for these.

 

PAL consoles allow the channel 2-3 switch just as the NTSC ones. But with PAL televisions, you can tune the channel from the television yourself, so you can actually pinpoint the exact location of the picture. This is not a channel issue anyway, because how come some orginal carts produce NO interference...

 

(that's always the thing that kills most explanations - SOME carts work just fine without any interference)

 

Do PAL consoles use RCA cables? If so, I'd be happy to send you the cable I've used successfully, with ferrite bead attached in the place where it worked best.

 

It is not a cable issue. How would the cable know to make only SOME carts interfere like crazy, but leave some carts totally interference-free? (again, the killer-peculiarity about this.. some carts work just fine)

 

- Monk

[Monk]

Fred, I have just compared Monk's video, in particular Harmony's Pitfall part, with my Harmony's Pitfall output.

I have found that the interferences are exactly in the same position!

So at least it's now clear that it's not a problem form outside (Monk, you can keep living near an airport!)

 

Well, it could still be an external interference problem, but some carts are just more SENSITIVE to it than others, and the interference makes the Atari just react in exact same way in both of our cases. I mean, it could be that any general interference (cell phone network perhaps? I heard they are not everywhere in US like they are here), powerful enough, would cause the Atari to 'reflect' it's microchips onto the screen somehow, or something. I know how stupid this sounds but I am very stupid when it comes to electronics (:

 

I hope to next week do those investigations, and bring more information on to the table again, so maybe with some patience we can eventually find out what the HECK exactly causes this problem.

 

It's like some carts are sensitive to something the Atari produces or reacts to, and then the carts react by outputting that interference. Or perhaps it's the other way around; the ATARI is sensitive to certain carts (but why?), and as a result, produces some weird effect just when it's supposed to output the picture onto the screen, resulting in that interference..

 

I don't know, I have absolutely NO explanations, just theories, all of which sound very odd.

 

- Monk

[Monk]

ok just putting my .02 cents in thats all.

 

Two hundredth of one cent? Wow, that's very little amount (-8

 

Did you pay with Paypal?

 

.02 is two cents

 

$.02 is 2 cents

.02 cents is $0.0002

like what ever dude.

 

 

He's actually correct. Besides, I was kinda joking anyway.. humor, you know?

 

But you did say ".02 cents", and NOT ".02 dollars" (which WOULD amount to two cents)..

 

With your definition .. .02 dollars is exactly same as two dollars! (that follows logically from .02 cents being the SAME as two cents - so mathematically:

 

0.02 = 2

 

Which simply isn't true of course.)

 

- Monk

[Thomas Jentzsch]

Ok, here's my theory:

 

Since it's not the cable, the shielding of the video units of the affected consoles has to be faulty. IMO you should open a console and have a look at the shielding (in the lower right).

[Monk]

Ok, here's my theory:

 

Since it's not the cable, the shielding of the video units of the affected consoles has to be faulty. IMO you should open a console and have a look at the shielding (in the lower right).

 

Sounds like a very good theory, but how come some carts are still clear - how does the shielding problem in Atari determine that "Ah, he's playing an original cart, I am not gonna exist now"..?

 

I mean, if this was in ALL carts, it would be so much easier to explain.. still, you may be right as perhaps some carts are just more SENSITIVE to this shielding problem.

 

Here is a video of the NTSC Atari 2600jr that I got all the way from USA yesterday..

 

http://www.youtube.com/watch?v=8rbwxi7pElk

 

As you see, I use Pitfall! as the 'control' game as it's so clear and easy-to-see in that one (in video, I mean - of course by naked eye it's very disturbing in most every game and also it produces much more fuzzy and unclear picture than the original carts that do not have the interference)..

 

So it's not a PAL vs. NTSC Atari-problem - it's an 'individual Atari'-problem, I reckon.

 

Btw, I don't know HOW to open that Atari.. I tried opening it once, but I couldn't get it opened, I didn't want to use too much force so nothing would break .. Besides, I wouldn't know what a 'shielding' looks like anyway.. I am not very electronically minded.

 

Here are some pictures of the NTSC Atari 2600jr that travelled to me from America.

[+Philsan]

Thomas, one of the two PAL consoles I've tested (2600 jr) is new.

What do you mean with "have a look at the shielding"?

What do we have to check?

 

But the problem happens with Harmony cart and not Pitfall cart (or other games we have tested).

If our console have shielding problems, it's strange that this problem causes troubles only to Harmony and not original carts.

 

 

[+wood_jl]

ok just putting my .02 cents in thats all.

 

Two hundredth of one cent? Wow, that's very little amount (-8

 

Did you pay with Paypal?

 

.02 is two cents

 

$.02 is 2 cents

.02 cents is $0.0002

like what ever dude.

 

 

He's actually correct. Besides, I was kinda joking anyway.. humor, you know?

 

But you did say ".02 cents", and NOT ".02 dollars" (which WOULD amount to two cents)..

 

With your definition .. .02 dollars is exactly same as two dollars! (that follows logically from .02 cents being the SAME as two cents - so mathematically:

 

0.02 = 2

 

Which simply isn't true of course.)

 

- Monk

 

To Dan: I didn't mean anything by it, either. I've written the same thing myself! Take care.

[Thomas Jentzsch]

Thomas, one of the two PAL consoles I've tested (2600 jr) is new.

What do you mean with "have a look at the shielding"?

What do we have to check?

I am no expert, but AFAIK the shielding has to be grounded to work efficiently. If the grounding is missing, the noise created by Harmony would directly go the video signal generation.

 

There is a sheed metal casing at the right of the Jr. board. This contains the video circuit.

 

Here is explained how to open the Jr.

 

But the problem happens with Harmony cart and not Pitfall cart (or other games we have tested).

If our console have shielding problems, it's strange that this problem causes troubles only to Harmony and not original carts.

We know that some carts produce more (a bit) interference than others. Maybe that's due to the chips used in there, not sure. Harmony produces much more, probably due to the relatively strong hardware used.

[Havok69]

So would this interference problem be eliminated with the S-Video mod?

[Thomas Jentzsch]

So would this interference problem be eliminated with the S-Video mod?

If my guess is right, then it should disappear.

[Monk]

We know that some carts produce more (a bit) interference than others. Maybe that's due to the chips used in there, not sure. Harmony produces much more, probably due to the relatively strong hardware used.

 

Thank you for the elaborate explanation and the pictures etc.

 

But that explanation, while probably the best one we have yet (except that 'loop' explanation that mr. Batari had, which was very good also), seems a bit flimsy. I mean, with Cosmic Ark, there's absolutely NO disturbing interference like that at all. I could buy your explanation if there was only some differences in how powerful the interference is, but it's more like ON/OFF-switch than any gradual difference.

 

I mean, either it's 100% or it's 0%. 32-in-1 cart has 100%, as does Harmony Cart - but Pitfall! and Cosmic Ark has 0%.

 

Can there really be this much difference in the strenght of the used chips, meaning that Cosmic Ark and Pitfall! would have SO WEAK chips to produce absolutely no interference whatsoever and yet show a perfect and beautiful picture?

 

That is a good explanation, I admit - but something about it just doesn't sit right.. if I was an electronically minded person, this could probably be easily tested by me. Perhaps Philsan can test this grounding theory and correct the shielding and see if it has any effect?

 

I mean, with a faulty Atari with incorrect/broken/faulty shielding, you'd think there would be at least _SOME_ interference in absolutely ALL cartridges.. wouldn't you?

 

- Monk

[+batari]

So would this interference problem be eliminated with the S-Video mod?

Yes, it would.

[+batari]

Just thought I'd mention that some think I am implying that the source of the interference is the cable or the Atari and not the Harmony. I am agreeing with you that Harmony is producing some level of RF interference that some other carts are not.

 

What I am wondering is if there is anything users can go do minimize the problem as redesigning Harmony circuit boards at this point is not a viable option. Short of a video mod, that is.

 

I am certainly not seeing the sort of interference from my NTSC Jr as others apparently are so it may indeed be something specific to certain consoles. Just to verify - is it only present in certain Jr consoles, or has anyone seen it in other consoles?

[Thomas Jentzsch]

I mean, either it's 100% or it's 0%. 32-in-1 cart has 100%, as does Harmony Cart - but Pitfall! and Cosmic Ark has 0%.

Like I said, I am no expert. But AFAIK interference comes from two (or more) waves overlapping. If some of those waves match, we get resonance. Which would explain why the differences are so huge. Some carts have no resonance frequency to the video signal and some have.

Edited January 8, 2010 by Thomas Jentzsch

[+Philsan]

Just to verify - is it only present in certain Jr consoles, or has anyone seen it in other consoles?

Yes, I have found the problem also in my 2600 (Darth Vader).

 

EDIT

I have now tested also my 4-switch VCS: nothing changes.

 

So, I have found the same interferences (exactly in the same part of screen) in 3 PAL consoles:

VCS (4-switch)

2600 (Darth Vader)

2600 Jr.

 

Every time I have changed power supply and video cable (also used CRT and LCD TVs).

[+batari]

Just to verify - is it only present in certain Jr consoles, or has anyone seen it in other consoles?

Yes, I have found the problem also in my 2600 (Darth Vader).

 

EDIT

I have now tested also my 4-switch VCS: nothing changes.

 

So, I have found the same interferences (exactly in the same part of screen) in 3 PAL consoles:

VCS (4-switch)

2600 (Darth Vader)

2600 Jr.

 

Every time I have changed power supply and video cable (also used CRT and LCD TVs).

Do you also get the same interference with the 32-in-1 cart? If so, I may have to acquire one of these and see what it has in common with Harmony.

[+Philsan]

Do you also get the same interference with the 32-in-1 cart? If so, I may have to acquire one of these and see what it has in common with Harmony.

Unfortunately I don't have the 32-in-1 cart.

 

I have tested 3 consoles with the same cart so I think we can exclude that some consoles are more sensible than others.

It's strange we have so far found the problem in only four Harmony carts.

I think you have sold many of them and not only to users with video mods (or blind ).

I don't think so but in this moment the results say it is an individual problem of our four carts.

 

EDIT

It's interesting what zagon has written:

If I wrap the cart with foil and ground the foil to the RF-shield the

interference is reduced to a great extent but still noticeable.

 

Fred, perhaps shielding cartridge's inside could be a viable design solution?

[Monk]

I have tested 3 consoles with the same cart so I think we can exclude that some consoles are more sensible than others.

 

I don't think we can rule that out at this point. Three carts is a very small amount, even if the two of my Atari's are added to it. But next week hopefully I can test it with Darth Vader model too.

 

We would still need to test with NTSC VCS and NTSC Darth Vader, but I think either the individual carts do it OR the individual Ataris just happen to have this kind of 'weak shielding' or 'frequency match' or whatever is causing it.

 

I will probably know more next week, but six Ataris could still be a coincidence.. I mean, how can we know what kind of percentage of Ataris have this problem, and what percentage is problem-free in this area?

 

In any case, I think mr. Batari would be advised to include some kind of disclaimer or warning with the Harmony Cart or it's selling page (if there is one yet), or something - at least some kind of small mention that this -might- happen.

 

Hopefully I can some day get an NTSC compatible television so I can test it with colors too, but I am pretty sure it'll still be there even with colors and sound.

 

Btw, that frequency overlapping theory is excellent and makes a lot of sense!

 

- Monk

[Monk]

Fred, perhaps shielding cartridge's inside could be a viable design solution?

 

This is a kind of thing I had in mind - perhaps mr. Batari could sell 'Interference-free' cartridges, just make a few of them (in a way that does not require redesigning it), and then sell to those who are bothered by the interference..

 

I had thought about also perhaps a silly idea but .. thinking that when I receive the second cartridge, and if things still remain the same with it, that if I would send them both back to mr. Batari, and pay of course all shipping back and forth, perhaps mr. Batari could send me some kind of interference-hack-version that wouldn't produce this anomaly to me, if I paid for his trouble and all - perhaps 20 or 30 bucks on top of what I have already paid so far?

 

I would be perfectly willing to do all this, if you are, mr. Batari.

 

But there's no rush of anything, I know how busy You must be and there are still other options to investigate and check out, but it was just an idea I was toying with in my head, and wanted to show it here for all to see.. what do you guys think, could this be somehow a viable thing?

 

- Monk

[accousticguitar]

You might need to send the Harmony cart and the problem 2600 console to him to really find out what's going on.

[+batari]

[/i]Fred, perhaps shielding cartridge's inside could be a viable design solution?

I would do that if I thought it would solve your issues. Unfortunately none of the developers who live in PAL regions have experienced problems with interference (with or without video mods) so this problem may be difficult to solve. At this point maybe it's best to wait until Monk receives another Harmony cart and see if this one has the same problem. I'll also see if I can obtain a 32-in-1 cart.